M.1 [NGC 1952]

[WH 1818 p. 345, SP2 p. 595]
"1783, 1794, 7 feet [FL] telescope. With 287 [magnification], light without stars."
"1805, 1809, 10 feet telescope. It is resolvable [mottled]. There does not seem any milky nebulosity miced with what I take to be small lucid points."
"1783, 1784, 1809, 20 feet telescope. Very bright, of an irregular figure; full 5 minutes in longest direction. I suspect it to consist of stars."
"1805, large 10 feet telescope. With 220 the diameter is 4'0"; with this power and light it is what must be called resolvable [mottled]."
As all the observations of the large telescopes agree to call this object resolvable, it is properly a cluster of stars at no very great distance beyond their gaging powers; its profundity may therefore be of about the 980th order. It is near the milky way.

M.2 [NGC 7089]

[WH 1800 p. 71-72, SP2 p. 44; WH 1814 p. 274-275, SP2 p. 535; WH 1818 p. 435-436, SP2 p. 595]
[1800]
July 30, 1783. I viewed the nebula south preceding Flamsteed's 24 Aquarii, discovered by Mr. Maraldi in 1746 [M2, NGC 7089].
"In the small sweeper (*), this nebula appears like a telescopic comet."
Oct. 27, 1794. The same nebula with a 7-feet reflector.
"I can see that it is a cluster of stars, many of them visible."
If we compare the penetrating power of the two instruments, we find that we have in the first sqrt(41*(42^2-12^2))/2 = 12.84; and in the latter sqrt(41*(63^2-12^2))/2 = 20.25. However, the magnifying power was partly concerned in this instance; for in the sweeper it was not sufficient to separate the stars properly.

---

The small sweeper is a Newtonian reflector, of 2 feet focal length; and, with an aperture of 4.2 inches, has only a magnifying power of 24. and a field of view 2d 12'. Its distinctness is so perfect, that it will shew letters at a moderate distance, with a magnifying power of 2000; and its movements are so convenient, that the eye remains at rest while the instrument makes a sweep from the horizon to the zenith. A large one of the same construction has an aperture of 9.2 inches, with a focal length of 5 feet 3 inches. It is also charged low enough for the eye to take in the whole optic pencil; and its penetrating power, with a double eye glass, is sqrt(41*(92^2-21^2))/2 = 28.57.

[1814]
Sept. 4, 1799. 40 feet telescope, power 240. "I examined the 2d of the Connoiss. [M2, NGC 7089]. It appeared very brilliamt and luminous."
"The scattered stars were brought to a good, well determined focus, from which it appears that the central condensed light is owing to a multitude of stars that appeared at various distances behind and near each other. I could actually see and distinguish the stars even in the central mass. The Rev. Mr. Vince, Plumian Professor of Astronomy at Cambridge, saw it in the same telescope as described."

[1818]
"1799, 7-feet finder of the telescope. It is visible as a star. 1810, it may just be perceived to have rather a larger diameter than a star."
"1783, 2 feet sweeper. It is like a telescopic comet."
"1794, 7 feet telescope. With 287 I can see that it is a cluster of stars, many of them being visible."
"1810, 10 feet telescope. A beautiful bright object."
"1784, 1785, 1802, 20 feet telescope."
"1805, 1810, large 10 feet telescope."
"1799, 40 feet telescope. A globular cluster of stars." (*) (*) For the particulars of this observation, see Phil Trans. for 1814, page 274 [SP 2, p. 535].
By the observation of the 7 feet telescope, which has a power of seeing stars that exceeds the power of the eye to see them by 20.25 times, the profundity of this cluster is of the 243rd order.

M.3 [NGC 5272]

[WH 1814 p. 276, SP2 p. 536; WH 1818 p. 436, SP2 p. 595]
[1814]
Sept. 24, 1810. Large 10 feet Newtonian telescope. Space penetrating power 75.82. Magnifying powers 71, 108, 171, 220. "The 3rd of the Connoiss. [M3, NGC 5272] is one of the globular clusters; very brilliant and beautiful. The compression of the stars begins to increase pretty suddenly from the outside at 3/4 of the radius, and continues gradually up to its centre, its diameter taking in the outside is full half of the field of the glass magnifying 171 times, giving 4'30"."

[1818]
The 3rd of the Connoissance.
"1813, 7 feet finder of the telescope. It is at a small distance from a star of equal brightness ; the star is clear, the object is hazy, and somewhat larger than the star."
"1783, 7 feet telescope. With 460 the light is so feeble that the object can hardly be seen; I suspect some stars in it. 1813, with 80, many stars are visible in it."
"1799, 10 feet telescope, power 120; with an aperture of 4 inches it is resolvable; with 5 easily resolvable; with 6 it is resolvable; with 7 and all open the stars may be easily perceived."
"1784, 1785, 20 feet telescope. A beautiful cluster of stars, about 5 or 6 minutes in diameter."
"1810, Large 10 feet telescope. With 171 the diameter is full 4'30". (*)" (*) see above observation from [WH 1814].
By the observation of the 7 feet telescope this cluster must be of the 243rd order.

M.4 [NGC 6121]

[WH 1814 p. 270, SP2 p. 533; WH 1818 p. 436-437, SP2 p. 595]
[WH 1814]
Connoiss. 4 is "A rich cluster of considerably compressed small stars surrounded by many straggling ones. It contains a ridge of stars running through the middle from south preceding [SW] to north following [NE]. The ridge contains 8 or 10 pretty bright stars. All the stars are red."
The curious construction of this cluster is sufficiently accounted for by the bright stars in what is called a ridge; the small stars accumulated about it having somewhat the appearance of the shelving sides of the ridge. The observed red colour was probably owing to the low situation of the object.

[WH 1818]
The 4th of the Connoissance.
"1783, 10 feet telescope. All resolved into stars. I can count a great number of them, while others escape the eye by their minuteness."
"1783, small 20 feet telescope. All resolved into stars."
"1784, 20 feet telescope. The cluster contains a ridge of stars in the middle, running from south preceding [SW] to north following [NE]."
The 10 feet telescope having a power to show stars exceeding that of the eye 28.67 times, gives the profundity of this cluster of the 344th order.

M.5 [NGC 5904]

[WH 1800 p. 73 & 75-76, SP2 p. 44 & 46; WH 1814 p. 275, SP2 p. 535; WH 1818 p. 437, SP2 p. 596]
[1800]
March 4, 1783. With the 7-feet reflector, I viewed the nebula near the 5th Serpentis, discovered by Mr. Messier, in 1764 [M 5 = NGC 5904].
"It has several stars in it; they are however too small that I can but just perceive some, and suspect others."
May 31, 1783. The same nebula with a 10-feet reflactor; penetrating power 1/2 * sqrt(43*(89^2-16^2)) = 28.67.
"With a magnifying power of 250, it is all resolved into stars: they are very close, and the appearance is beautiful. With 600, perfectly resolved. There is a considerable star not far from the middle; another not far from one side, but out of the cluster; another pretty bright one; a great number of small ones."
Here we have a case where the penetrating power of 20 fell short, when 29 resolved the nebula completely. This object requires also great magnifying power to shew the stars of it well; but that power had before been tried, in the 7-feet, as far as 460, without success, and could only give an indication of its being composed of stars; whereas the lower magnifying power of 250, with a greater penetrating power, in the 10-feet instrument, resolved the whole nebula into stars.
Feb. 24, 1786. I viewed the nebula near Flamsteed's 5 Serpentis, which has been mentioned before [M 5] with my 20-feet reflector; magnifying power 157.
"The most beautiful extremely compressed cluster of small stars; the greatest part of them gathered together into a brilliant nucleus, evidently consisting of stars, surrounded with many detached gathering stars of the same size and colour. R.A. 15h 7' 12"; P.D. 87d 8'."
May 27, 1791. I viewed the same object with my 40-feet telescope; penetrating power sqrt(64*480|^2)/2 = 191.69; magnifying power 370.
"A beautiful cluster of stars. I counted about 200 of them. The middle of it is so compressed that it is impossible to distinguish the stars."

[1814]
May 27, 1791. 40 feet telescope, power 370. "The 5th of the Connoiss. [M 5 = NGC 5904] is a beautiful cluster of stars; I counted 200 of them; but the middle of it is so compressed that it is impossible to distinguish the stars." (*)

---

(*) A 40 feet telescope should only be used for examining objects that other instruments will not reach. To look through one larger than required is loss of time, which, in a fine night, an astronomer has not to spare; but it ought to be known that the opportunities of using the 40 feet reflector are rendered very scarce by two material circumstances. The first is the changable temperature of the atmosphere, by which the mirror is often covered with condensation of vapour upon its surface, which renders it useless for many hours; and in cold weather by freezing upon it for the whole night, and even for weeks together; for the ice cannot be safely taken off till a general thaw removes it. The next is that, with all imaginable care, the polish of a mirror exposed like that of the 40 feet telescope, though well covered up, will only preserve its required lustre and delicacy about two years. The three observations I have given must consequently be looked upon as having been made by three different mirrors; but if we will have superior views of the heavens, we must submit to circumstances that cannot easily be altered.

[1818]
The 5th of the Connoissance. [M 5 = NGC 5904]
"1813, 7 feet finder. It is near a star of equal brightness; the star is clear but the object is hazy."
"1783, 7 feet telescope. It consists of stars; they are however so small that I can but just perceive some, and suspect others. 1810, the globular figure is visible."
"1783, 10 feet telescope. With 600, all resolved into stars."
"1785, 1786, 20 feet telescope. A very compressed cluster of stars, 7 or 8 minutes in diameter; the greatest compression about 2 or 2 1/2 minutes."
"1792, 40 feet telescope. With 370 I counted about 200 stars; the middle is so compressed, that it is impossible to distinguish the stars."
The profundity of this cluster, by the observation of the 7 feet telescope, is of the 243d order.

M.6 [NGC 6405]

[WH 1814 p. 266, SP2 p. 530; SP2 p. 651]
[1814]
Connois. 6 is "A cluster of stars of various sizes containing several lines that seem to be drawing to a centre like a forming cluster."

[SP2]
1783, July 30. 20 feet, lowest power. I counted about 50 stars; it contains the greatest variety of magnitudes of any nebula I recollect. The compound eye-piece shows more of them variously and intermixed.
1786, Apr. 30 (Sw. 559). Contains several lines that seem to be drawing to a center like a forming cluster.

M.7 [NGC 6475]

[SP2 p. 651]
1783, July 30. About 20 stars. [Only seen once.]

M.8 [NGC 6523]

[SP2 p. 651-652]
1784 May 22 (Sw. 223). L. E. pB. broad. [Large, Extended (elongated), pretty bright, broad.] The nebulosity of the milky kind, there are some pB [pretty bright] stars in it, but they seem to have no connection w3ith it, being of very different sizes [magnitudes] and colours and resembling the other stars that are everywhere scattered about in this neighborhood. This is probably the star surrounded with nebulosity mentioned by Messier. There is indeed one of the stars which are in the nebula that is somewhat larger [brighter] than the rest and may be the only one he saw. The nebula follows 51 Ophiuchi 32'.4 in time and is 35' more south.

M.9 [NGC 6333]

[WH 1800 p. 73, SP2 p. 45; WH 1814 p. 278, SP2 p. 538; WH 1818 p. 437-438, SP2 p. 596]
[1800]
May 3, 1783. I viewed the nebula between Eta and Rho Ophiuchi, discovered by Mr. Messier, in 1764 [M 9 = NGC 6333].
"With a 10-feet reflector, and a magnifying power of 250, I see several stars in it, and make no doubt a higher power, and more light, will resolve it all into stars. This seems to be a good nebula for the purpose of establishing the connection between nebulae and clusters of stars in general."
June 18, 1784. The same nebula viewed with a large Newtonian 20-feet reflector; penetrating power sqrt(43*(188^2-21^2))/2 = 61.18; and a magnifyingpower of 157. "A bery large and very bright cluster of excessively compressed stars. The stars are but just visible, and are of unequal magnitudes: the large stars are red; and the cluster is a miniature of that near Flamsteed's 42d Comae Berenices [M53]. RA 17h 6' 32"; P.D. 108d 18'."
Here, a penetrating power of 29, with a magnifying power of 250, would barely shew a few stars; when, in the other instrument, a power 61 of the first sort, and only 157 of the latter, shewed them completely well.

[1814]
Connoiss. 9 [M 9 = NGC 6333] is "A cluster of very compressed and extremely small stars. It is a miniature of the 53d [M53]."

[1818]
The 9th of the Connoissance.
"1783, 10 feet telescope, power 250. I see several stars in it; and have no doubt a higher power and more light will resolve it into stars."
"1784, 1786, 20 feet telescope. A cluster of extremely compressed stars; it is a miniature of the 53d [M 53]."
By the observations of the 10 feet the profundity is at least of the 344th order. It is in the preceding branch of the milky way.

M.10 [NGC 6254]

[WH 1800 p. 74, SP2 p. 46 (footnote); WH 1818 p. 438, SP2 p. 596]
[1800]
[M14 resembles M10 if it [M10] would be 1.5 times as far as it is.] The object referred to is No. 10 of the Connoissance des Temps for 1783, called "Nébuleuse sans étoile." My description of it is, "A very beautiful, and extremely compressed, cluster of stars; the most compressed part about 3 or 4' in diameter. R.A. 16h 46' 2"; P.D. 93d 46'."

[1818]
The 10th of the Connoissance. [M 10 = NGC 6254]
"1783, 7 feet telescope. With 227 I suspected it to consist of stars; with 460 I can see several of them, but they are too small to be counted."
"1784, 1791, 20 feet telescope. A beautiful cluster of extremely compressed stars; it resembles the 53d [M53]; and the most compressed part is about 3 or 4 minutes in diameter."
The profundity of this cluster, by the observation of the 7 feet telescope, is of the 243d order.

M.11 [NGC 6705]

[WH 1818 p. 438, SP2 p. 596]
The 11th of the Connoissance. [M 11 = NGC 6705]
"1799, 10 feet finder. The cluster is visible; and, directed by neighboring stars, it may be seen by the eye."
"1783, 1799, 10 feet telescope. Power 300. With 3 inches aperture, the small stars are not to be distinguished; with 4 inch I can see them."
"1803, 1810, large 10 feet telescope. The cluster is of an irregular form, from 9 to 12 minutes in diameter."
The 10 feet telescope with an aperture of 4 inches, had a gauging power of 12.02; the profundity of this cluster is therefore of the 144th order. It is in the milky way.

M.12 [NGC 6218]

[WH 1818 p. 438-439, SP2 p. 596]
The 12th of the Connoissance. [M 12 = NGC 6218]
"1799, 10 feet finder. The object is visible in it."
"1783, 1799, 10 feet telescope. With 120, and an aperture of 4 inches, easily resolvable; with 5 inches, stars become visible; with 6 inches, pretty distinctly visible; and with all open, the lowest power shows the stars."
"1785, 1786, 20 feet telescope. A brilliant cluster, 7 or 8 minutes in diameter; the most compressed parts about 2 minutes."
With an aperture of 5 inches the 10 feet telescope had a gauging power of 15.53; and this cluster is consequently of a profundity of the 186th order.

M.13 [NGC 6205]

[WH 1814 p. 275-276, SP2 p. 536; WH 1818 p. 439, SP2 p. 597]
[1814]
May 16, 1787. 20 feet telescope. "The 13th of the Connoiss. [M 13 = NGC 6205] is a most beautiful cluster of stars. It is exceedingly compressed in the middle and very rich. The most compressed part of it is round and is about 2 or 2 1/2' in diameter, the scattered stars which belong to it extend to 8 or 9' in diameter, but are irregular." (*)

---

(*) The 20 feet telescope, on account of the moderate weight of the mirror and the proportionally long wooden tube, has the great advantage that with proper precaution it may be used at any temperature. Sometimes, however, a sudden change from cold to heat towards the morning has put a stop to the observations of the night. The mirror will also preserve an excellent polish for several years; and having a second one ready to supply the place of that which is in use the instrument may always be ready for observation.

[1818]
The 13th of the Connoissance. [M 13 = NGC 6205]
"1799, 1805. It is plainly to be seen to the eye."
"1799, 7 feet finder. Very visible."
"1783. 7 feet telescope. With 227 plainly resolved into stars."
"1799, 10 feet telescope. With an aperture of 4 inches the stars cannot be distinguished; with 9 inches, very beautiful."
"1787, 1799, 20 feet telescope. The stars belonging to the cluster extend to 8 or 9 minutes in diameter; the most compressed part about 2 or 2 1/2; the latter is round, the former irregular."
"1805, large 10 feet telescope. A brilliant cluster all resolved into stars. The space penetrating power of this Newtonian reflector is sqrt(41*(240^2-39^2))/2 = 75.82"
By the observation of the 7 feet telescope, the profundity of this cluster is nearly of the 243d order.

M.14 [NGC 6402]

[WH 1800 p. 74-75, SP2 p. 45; WH 1814 p. 278, SP2 p. 538; WH 1818 p. 440, SP2 p. 597]
[1800]
July 30, 1783. With a small 20-feet Newtonian reflector, I viewed the nebula in the hand of Serpentarius [Ophiuchus], discovered by Mr. Messier, in 1764 [M 14 = NGC 6402].
"With a power of 200, I see it consists of stars. They are better visible with 300. With 600, they are too obscure to be distinguished, though the appearance of stars is still preserved. This seems to be one of the most difficult objects to be resolved. With me, there is not a doubt remaining; but another person, in order to form a judgement, ought previously to go through all the several gradations of nebulae which I have resolved into stars.
May 25, 1791. I viewed the same nebula with a 20-feet reflector of my construction, having a penetrating power of sqrt(64*188|^2)/2 = 75.08.
"With a magnifying power of 157, it appears extremely bright, round, and easily resolvable. With 300, I can see the stars. It resembles the cluster of stars taken at 16h 43' 40" [M10], which probably would put on the same appearance as this, if it were at a distance half as far again as it is."

[1814]
Connoiss. 14 [M 14 = NGC 6402] is "Like an extremely bright, easily resolvable round nebula; but with a power of 300 I can see the stars of it. It resembles the 10th of the Connoiss. [M 10] which would probably put on the same appearance as this, were it removed half its distance farther from us. The stars are much condensed in the middle."

[1818]
The 14th of the Connoissance. [M 14 = NGC 6402]
"1783, 7 feet telescope.With 227, there is a strong suspicion of its consisting of stars."
"1783, 1784, 1791, 1799, 20 feet telescope. Extremely bright, round, easily resolvable; with 300 I can seethe stars. The heavens are pretty rich in stars of a certain size, but they are larger than those in the cluster, and easily to be distinguished from them. The cluster is considerably behind the scattered stars, as some of them are projected upon it."
From the observations with the 20 foot telescope, which in 1791 and 1799 had the power of discerning stars 75.08 times as far as the eye, the profundity of this cluster must be of the 900th order.

M.15 [NGC 7078]

[WH 1814 p. 276, SP2 p. 536; WH 1818 p. 440-441, SP2 p. 597]
[1814]
Nov. 23, 1805. Large 10 feet. "The 15th of the Connoiss. [M 15 = NGC 7078] is perfectly round, and insulated. The accumulation of stars towards the centre is more sudden that the 13th of the Connoiss. [M 13] and the scattered stars extend proportionally much farther. Its diameter is 1/6 of the field of the glass which magnifies 108 times, that is to say 4'0". It passes the wire in 13".0 of time which by calculation gives only 2'11".3, but I rely more on the estimation by the known field of view which is 24'0"; because the limits of the cluster cannot be properly fixed upon transit."

[1818]
The 15th of the Connoissance. [M 15 = NGC 7078]
"1799. It is visible to the eye."
"1783, 1794, 7 feet telescope. With 278 the stars of the cluster may be seen."
"1799, 10 feet telescope. With an aperture of 4 inches, no trace of stars is visible. 1817, with an aperture of 4.56 inches, which gives a gaging power of 14, it appears like a nebulous patch, gradually brighter in the middle; with a gaging power of 16, the hazy border is larger; with 18, the whole of it much larger and brighter; with 20, resolvable; and with 22, the stars are visible."
"1784, 1787, 1807, 20 feet telescope. A globular cluster of stars, about 6 minutes in diameter."
"1810, large 10 feet telescope. The diameter, with 171, is full 4'30", and taking in the stars that probably belong to it, it is 6'45"."
By the observation of the 7 feet telescope, the profundity of this cluster is of the 243d order.

M.16 [NGC 6611]

[SP2 p. 652]
1783, July 30. Large stars with small ones among them; within a small compass I counted more than 50, and there must be at least 100 without taking in a number of straggling ones, everywhere dispersed in the neighborhood.

M.17 [NGC 6618]

[SP2 p. 652]
1783, July 31. A very singular nebula; it seems to be the link to join the nebula in Orion to others, for this is not without a possibility of being stars. I think a great deal more of light and a much higher power would be of service.
1784, June 22 (Sw. 231). A wonderful nebula. Very much extended, with a hook on the preceding [Western] side; the nebulosity of the milky kind; several stars visible in it, but they seem to have no connection with the nebula, which is far more distant. I saw it only through short intervals of flying clouds and haziness; but the extent of the light including the hook is above 10'. I suspect besides, that on the following [Eastern] side it goes on much farther and diffuses itself towards the north and south. It is not of equal brightness throughout and has one or more places where the milky nebulosity seems to degenerate into the resolvable [mottled] kind; such a one is that just following the hook towards the north. Should this be confirmed on a very fine night, it would bring on the step between these two nebulosities which is at present wanting, and would lead us to surmise that this nebula is a stupendous stratum of immensely distant fixed stars, some of whose branches come near enough to us to be visible as a resolvable nebulosity, while the rest runs on to so great a distance as only to appear under the milky form.

M.18 [NGC 6613]

[SP2 p. 652]
1783, July 31. About 20 L. [large; bright] and sev. S. [several small; faint] stars irregularly scattered.
1784, June 22 (Sw. 231). A cl. [cluster] of coarsely scattered L. [large; bright] stars, not rich.

M.19 [NGC 6273]

[WH 1814 p. 277, SP2 p. 537 (*); WH 1818 p. 441, SP2 p. 597; (*) Dreyer's note: The observation quoted in that place cannot be found]
[1814]
[Jan. 13, 1806?] Common 10 feet telescope. Space penetrating power 28.67. "When the 19th of the Connoiss. is viewed with a magnifying power of 120, the stars are visible; the cluster is insulated; some of the small stars scattered in the neighborhood are near it; but they are larger than those belonging to the cluster. With 240 it is better resolved, and is much condensed in the centre. With 300 no nucleus or central body can be seen. The diameter with the 10 feet is 3'16", and the stars in the centre are too accumulated to be separately seen."
It will not be necessary to add that the two last mentioned globular clusters [M19 and M53], viewed with more powerful instruments, are of equal beauty with the rest; and from what has been said it is obvious that here the exertion of a clustering power has brought the accumulation and artificial construction of these wonderful celestial objects to the highest degree of mysterious perfection.

[1818]
The 19th of the Connoissance. [M 19 = NGC 6273]
"1783, 10 feet telescope. With 250, I can see 5 or 6 stars,a nd all the rest appears mottled like other objects of its kind, when not sufficiently magnified or illuminated." (*: Compare above [1814])
"1784, 20 feet telescope. A cluster of very compressed stars, much accumulated in the middle; 4 or 5 minutes diameter."
By the observation of the 10 feet telescope, the profundity of this cluster is of the 344th order. It is in the preceding branch of the milky way.

M.20 [NGC 6514]

[SP2 p. 652]
1783, May 3. Two nebulae close together, both resolvable into stars; the preceding however leaves some doubt, though I suppose a higher power and more light would confirm the conjecture. 10 feet, power 350: the instrument will not bear a higher power in this low altitude.

M.21 [NGC 6531]

[SP2 p. 652]
1786, May 26 (Sw. 556). A rich cluster of large [bright] stars.

M.22 [NGC 6656]

[WH 1800 p. 73-74, SP2 p. 45; WH 1818 p. 441, SP2 p. 597]
[1800]
July 4, 1783. I viewed the nebula between Flamsteed's 25 and 26 Sagittarii, discovered by Abraham Ihle, in 1665 [M 22 = NGC 6656].
"With a small 20-feet Newtonian telescope, power 200, it is all resolved into stars, that are very small and close. There must be some hundreds of them. With 350, I see the stars very plainly; but the nebula is too low in this latitude for such a power."
July 12, 1784. I viewed the same nebula with a large 20-feet Newtonian reflector, power 157. "A most beautiful extensive cluster of stars, of various magnitudes, very compressed in the middle, and about 8' in diameter, besides the scattered ones, which do fill the extent of the field of view [This field, by the passage of an equatorial star, was 15'3"]: the large stars are red; the small ones are pale red. R.A. 18h 23' 39"; P.D. 114d 7'."
The penetrating power of the first instrument was 39, that of the latter 61; but, from the observations, it is plain how much superior the effect of the latter was to that of the former, notwithstanding the magnifying power was so much in favour of the instrument with the small penetrating power.

[1818]
The 22nd of the Connoissance. [M 22 = NGC 6656]
"1783, 7 feet telescope. 460 has not light enough to show it; with 227, I see it very imperfectly."
"1801, 10 feet telescope. With 600 it is a cluster of stars."
"1783, small 20 feet telescope. With 350, all resolved into stars."
"1784, 20 feet telescope. An extensive cluster of stars."
"1810, large 10 feet telescope. The stars are condensed in the middle. The diameter is 8' 0"; the greatest condensation is about 4'0"."
By the observation of the 10 feet telescope, the profundity of this cluster must be nearly of the 344th order. It is near the following branch of the milky way.

M.23 [NGC 6494]

[SP2 p. 652]
1784, June 18 [Sw. 230). A cluster of beautiful scattered, large stars, nearly of equal magnitudes (visible in my finder), it extends much farther than the field of the telescope will take in, and in the finder seems to be a nebula of a lenthened form extending to about half a degree.

M.24 [with NGC 6603; IC 4715?]

[SP2 p. 652]
1783, Aug. 2. Considerable stars in great number.

M.25 [IC 4725]

[SP2 p. 652; Dreyer's remark: Not in NGC, 18h 23m, 109d 2' for 1860]
1783, July 30. Very large [bright] stars and some small [faint] ones; I counted 70, and there are many more within no considerable extent.

M.26 [NGC 6694]

[SP2 p. 652]
A cluster of scattered stars, not rich.

M.27 [NGC 6853, The "Dumb-bell"]

[SP2 p. 653]
1782, Sept. 30. My sister discovered this nebula this evening in sweeping for comets; on comparing its place with Messier's nebulae we find it is his 27. It is very curious with a compound piece; the shape of it though oval as M. [Messier] calls it, is rather divided in two; it is situated among a number of small [faint] stars, but with this compound piece no star is visible in it. I can only make it bear 278. It vanishes with higher powers on account of its feeble light. With 278 the division between the two patches is stronger, because the intermediate faint light vanishes more.
1783, Aug. 2. A distant suspicion of its being all stars; I want light.
1784, July 19 (Sw. 241). This nebula I suppose to be a double stratum of stars of a very great extent. The ends next to us are not only resolvable nebulosity; farther on the nebulosity it is but barely resolvable, and ends at last in milky whitishness of the same appearance as that in Orion. The idea I form of the shape of the strata is this: -
[drawing follows]
These two being laid on each other, A on A and viewed from B, so as to have the small round end A foremost , may produce the appearance of this curious nebula.
1794, October 27. With 287, 7feet reflector, I see only two patches of light joined together, like tow nebulae without stars, running into one another. There are a few very small stars visible in it, but no more than what in the rest of the heavens are scattered about. They therefore are not connected with the nebula or nebulae.

M.28 [NGC 6626]

[SP2 p. 653]
1799, August 1. It may be called insulated though situated in a part of the heavens that is very rich in stars. It may have a nucleus, for it is much compressed towards the centre, and the situation is too low for seeing it well. The stars of the cluster are pretty numerous.

M.29 [NGC 6913]

[SP2 p. 653]
1794, October 27. Is not sufficiently marked in the heavens to deserve notice, as 7 or 8 small [faint] stars together are so frequent about this part of the heavens that one might find them by hundreds.

M.30 [NGC 7099]

[WH 1814 p. 270-271, SP2 p. 533; WH 1818 p. 442, SP2 p. 598]
[1814]
Connoiss. 30 is "A brilliant cluster, the stars of which are gradually more compressed in the middle. It is insulated, that is, none of the stars in the neighborhood are likely to be connected with it. Its diameter is from 2'40" to 3'30". The figure is irregularly round. The stars about the centre are so much compressed as to appear to run together. Towards the north, are two rows of bright stars 4 or 5 in a line."
In this accumulation of stars, we plainly see the exertion of a central clustering power, which may reside in a central mass, or, what is more probable, in the compound energy of the stars about the centre. The lines of bright stars, although by a drawing made at the time of observation, one of them seems to pass through the cluster, are probably not connected with it.

[1818]
The 30th of the Connoissance. [M 30 = NGC 7099]
"1794, 7 feet finder. It is but just visible."
"1794, 7 feet telescope. It seems to be resolvable, but is too faint to bear a high power."
"1810, 10 feet telescope. With 71, it appears like a pretty large cometic nebula, very gradually much brighter in the middle. 1783, with 250 it is resolved into very small stars."
"1783, small 20 feet Newtonian, 12 inch diameter. Power 200; it consists of very small stars; with two rows of stars, 4 or 5 in a line."
"1783, large 20 feet Newtonian. Power 120; by a drawing of the cluster, the rows of stars probably do not belong to the cluster."
"1784, 1785, 1786, 20 feet telescope, power 157. A brilliant cluster."
"1810, large 10 feet telescope. With 171 and 220 the diametr is 3' 5"; it is not round."
By the observation of the 10 feet telescope, the profundity of this cluster is of the 344th order.

M.31 [NGC 224, nebula in Andromeda]

[WH 1814 p. 260, SP2 p. 527]
Connoiss. 31 [M 31 = NGC 224] is "A large nucleus with very extensive nebulous branches, but the nucleus is very gradually joined to them. The stars which are scattered over it appear to be behind it, and seem to lose part of their lustre in the passage of their light through the nebulosity; there are not more of them scattered over the nebula than there are over the immediate neighbourhood. I examined it in the meridian with a mirror 24 inches in diameter, and saw it in high perfection; but its nature remains mysterious. Its light, instead of appearing resolvable with aperture, seemed to be more milky."

M.32 [NGC 221]

[SP2 p. 653]
1813, Dec. 26. A vB. R. nebula, vgbM. up to a nucleus [A very bright, round nebula, very gradually brighter to the middle up to a nucleus].

M.33 [NGC 598]

[WH 1786 p. 494, SP1 p. ; WH 1800 p. 78-79, SP2 p. 48; WH 1818 p. 442-443, SP2 p. 598; SP2 p. 653]
[1786]
H V.17. Sept. 11, 1784.
m. [milky] nebulosity. not less than 1/2 deg. broad, perhaps 3/4 degree long, but not determined.

[1800]
August 24, 1783. I viewed the nebula north preceding Flamsteed's 1 Trianguli, discovered by Mr. Messier, in 1764 [M 33 = NGC 598].
"7-feet reflector; power 57. There is a suspicion that the nebula consists of exceedingly small stars. With this low power it has a nebulous appearance; and it vanishes when I pus on the higher magnifying powers of 278 and 460."
Oct. 28, 1794. I viewed the same nebula with a 7-feet reflector.
"It is large, but very faint. With 120, it seems to be composed of stars, and I think I see several of them; but it will bear no magnifying power."

[1818]
The 33rd of the Connoissance. [M 33 = NGC 598]
"1799, 10 feet finder. It is visible as a faint nebula."
"1783, 1794, 7 feet telescope. With 75, it has a nebulous appearance; it will not bear 278 and 460, but with 120 it seems to be composed of stars."
"1799, 1810, 10 feet telescope. The brightest part is resolvable; some of the stars are visible."
"1805, 1810, Large 10 feet telescope. The condensation of the stars is very gradually towards the middle; but with the four powers 71, 108, 171, and 220, some nebulosity remains. The stars of the cluster are the smallest points imaginable. The diameter is nearly 18 minutes."
The profindity of this cluster, by the observation of the 10 inch telescope, must be of the 344th order.

[SP2 p. 653]
See above pp. 48 and 598. Two observations are recorded as being of V.17, the outlying parts of the great nebula; they were made September 11 and 12, 1784, and described in vol. i. [SP1] pp. 255-256.

M.34 [NGC 1039]

[WH 1818 p. 443, SP2 p. 598]
The 34th of the Connoissance. [M 34 = NGC 1039]
"1799, 7 feet finder. It is visible."
"1783, 1794, 7 feet telescope. A cluster of stars; with 120, I think it is accompanied with mottled light, like stars at a distance."
"1784, 1786, 20 feet telescope. A coarse cluster of large stars of different sizes."
By the observation of the 7 feet telescope, the profundity of this cluster does probably not exceed the 144th order.

M.35 [NGC 2168]

[WH 1818 p. 443, SP2 p. 598]
The 35th of the Connoissance. [M 35 = NGC 2168]
"1794, It is visible to the naked eye as a very small cloudiness."
"1783, 1784, 1801, 1813, 7 feet telescope. It is a rich cluster of stars of various sizes."
"1806, 10 feet telescope. There is no central condensation to denote a globular form."
"1784, 1786, 20 feet telescope. A cluster of pretty compressed large stars."
The profundity of this cluster does probably not exceed the 144th order. It is in the milky way.

M.36 [NGC 1960]

[SP2 p. 653]
1794, Oct. 28. 7 feet reflector. With 120, a pretty rich cluster of small [faint] stars, seems to have many more than are visible, very small [faint].

M.37 [NGC 2099]

[SP2 p. 653-4]
1782, Nov. 4. Is an astonishing number of small stars with 227; they are almost all of the 2ndor 3rd class. I see no kind of nebulosity in the spot. With 460 the whole is resolvable into stars without nebulosity.
1783, August 24. A useful, coarse step; it will serve to learn to see nebulae, because it contains many small stars mixed with others in various magnitudes, many of which are not to be seen without great and long attention.

M.38 [NGC 1912]

[SP2 p. 654]
1805, Nov. 23, Review. Large 10 feet reflector. A cluster of scattered, pretty large [bright] stars of various magnitudes, of an irregular figure. It is in the Milky Way.

M.39 [NGC 7092]

[SP2 p. 654]
1788, Sept. 27 (Sw. 866). Consists of such large and straggling stars that I could not tell where it began nor where it ended. It cannot be called a cluster.

M.40

[SP2 p. 654]
1799, Aug. 5. Not visible in the finder.
[Dreyer's remark, after quoting Messier's description: Only once looked for by Herschel; Messier only inserted it because he had found it when looking for a nebula alleged to be in that neighborhood.]

M.41 [NGC 2287]

[SP2 p. 654]
1784, Oct. 20 (Sw. 304). A large cluster of very coarsely scattered large [bright] stars.

M.42 and M.43 [NGC 1976 and NGC 1982, Great Nebula in Orion]

[SP2 p. 654-657 (*)]
(*) Dreyer's note: The following observations have already appeared in print in Holden's "Monograph of the Central Parts of the Nebula of Orion," Washington Observations for 1878, Appendix I., but only copied from Caroline Herschel's transcript and not from the original Journal. They are here given in full on account of the special interest attaching this object. The rough pen-and-ink sketch made on March 4, 1774, was copied on the plate belonging to the paper of 1811, see Pl. III, fig 37; compare p. 465 [of SP2].
1774, March 1. Observed the Lucid Spot in Orion's sword belt; but the air not being very clear, it appeared not distinct.
1774, March 4. Saw the lucid spot in Orion's sword thro' a 5 1/2 foot reflector; its shape was not as Dr Smith has delineated in his Optics; tho' something resembling it, being as follows [Plate III, fig. 37]. From this we may infer that there are undoubtedly changes among the fixt stars, and perhaps from a careful observation of this spot something might be concluded concerning the nature of it.
1776, Nov. 11. The lucid spot in Orion, about 10 o'clock just rising at 5d high [see diagram, 1779 Oct. 7]. The greatest glare immediately about the 3 small stars 2, 5, 6 in the corner, the middle whereof is one or two magnitudes larger than the other two. The three succeeding stars 1, 3, 4 were almost on the upper side of this figure free from any glare, and there was a total darkness in the corner by the 3 before mentioned close in the corner. There was a very faint glimmering of a seventh star which I have marked but which must be several magnitudes less than the other 6. The two Nos. 1 2 were of one size, the two 3 4 next, the two 5 6 considerably less and 7 very much less again, almost invisible. The whole was exceedingly distinct. Instrument 10 ft. reflector, power 120. There was also an 8th star visible near the 6th with the same small size with the 7th or rather less.
1778, Jan. 25. Die Nebula im Orion [sic!] from 10 to 12 o'clock. In the east the lucid ray seems to make an equilateral (*) triangle with the stars 1 & 3 where one is the vertex and seems from the base to go on in the direction of 1 3 4 rather approaching to 4 and afterwards bend round 4 in an angle of about 110 to 120 degrees to the east. From 2 to 7 the lucid part is concave, the concave part turned towards 3, and goes to the northwest about 3/4 of the distance from 2 to 7; it turns from thence to west in angle of about 75 or 70.

---

(*) [Over this word ("equilateral") is written in pencil "isosceles." - Ed. (Dreyer)]
1778, Jan. 26. From 10 to 12, observation of the Nebula. 6.2.1 make a straight line.
6.8.7 make a straight line. The lines 2 . 5 and 1 . 3 . 4 diverge; 5 a little larger than 6; 4, 5, 8 make a straight line.
1778, Feb. 7. 11h 30'. I observed the Lucid Spot again and saw all 4 stars very well, and their place agreed with the observation of Jan. 25.
1778, Feb. 25. I observed the Lucid Spot in Orion when on and near the meridian and found everything in regard to the situation of the 4 little stars to agree with the observation of Jan. 25.
1778, Dec. 15. Lucid Spot in Orion's sword handle. 6 . 8 . 7 make a straight line.
6 . 2 . 1 make a straight line.
4 . 5 . 8 make a straight line. The lines 2 . 5 and 1 . 3 . 4 diverge. This agrees with the observation of Jan. 26. But there is a visible alternation in the figure og the lucid part.
1779, Oct 7. Theta Orionis. The line 6 . 2 . 1 is a little convex towards 5, when that line is taken into the middle of the field; this I mention, as it is possible there might be a little curvature arising from the spherical figure of the eyepiece, tho' I believe there is not. If a line be drawn from 6 to 7, the star 8 stands outward I suppose no less than 15deg, so that 6 . 8 . 7 is concave towards the side 1 . 3 . 4. The line 4 . 5 . 8 I cannot very well compare, being rather too far distant by the power I now use, but I believe it is not far from a right line. I see a 9th star which is marked in annexed figure, where however not the least exactness is intended. Altitude about 26 degrees. 14h 10'. The figure of the lucid part is much altered.
[With this observation is a sketch of the stars 1..9; Trapezium is 2,5,6,8]
1779, Dec. 5. 6 . 2 . 1 concave, the concave part turned to the south. 8 . 6 . 7 still makes an angle at 6, tho' very small. I see the 9th star mentioned [Oct. 7].
1780, Jan 22. 10h 30'. The stars 6 . 2 . 1 instead of seeming concave towards the north appear convex. This may however be a deception as the star 2 is the largest, and since there is pretty strong aberration on account of a fog, its diameter is more increased than that of 6 and consequently may give the balance towards the north.
1780, Feb. 19. Exactly as described [Oct. 7, 1779].
1780, Feb 28. The two stars 6 . 2 measure 12".812; the measure is pretty narrow, but I believe true enough. The two stars 2 . 5 measure 14".271, this is also a pretty narrow but just measure. The two stars 6 . 8 measure about 9".062, but this is doubtful on account of the obscurity of the stars 8, which is hardly perceptible when the field of view is illuminated properly so as to make the parallel hair very distinct. The two stars 5 . 8 measure 20".521. This is also doubtful on the same account.
1780, Oct. 10. Theta. The upper stars concave by the hair, the spot extremely fine. The 4 stars are all full and well defined.
1780, Nov. 24. 12h. The Nebula in Orion is very fine indeed. I perceive not the least alteration.
1783, Jan. 31. Theta Orionis. The Nebula quite different from what it was last year. The 9th star very strong.
1783, Sept. 20. The Neb. in Orion has evidently changed its shape since I saw it last. The star under the nebula is nebulous. 20 ft., 200.
1783, Sept. 28. Surprising changes in the Nebula Orionis.
1783, Nov. 3. The Nebula in Orion is beautiful, and I see several circumstances which I never observed with other instruments, viz. just close to the four stars it is totally black for a very short space, a few seconds. Below, in the open black part is a small distinct nebula of an extended shape. (*) The eastern branch of the great nebula extends very far; it passes between two very small stars and runson so far as to meet a pretty bright star. The nebulous star below the nebula is not equally surrounded, but most towards the south; on the north of this lesser nebula it is joined by one still fainter, which makes a rectangular corner by its meeting the small nebula.

---

(*) [This is III.1, an appendage to Messier 43. - Ed. (Dreyer)]
1784, Oct. 16 (Sweep 296). The beginning of the neb., 5 Monocerotis p. 41' 6" n 0d 43'. My small neb. is just under the south following corner of the great one. The 43rd [M43] is not a nebulous star, the star not being at all in the center of it; my little one makes a part of it. It is altogether the most wonderful object in the heavens.
1784, Dec. 20. The nebula in Orion as before described, but the moon being bright it seems to extend hardly 3/4 of a degree.
1785, Feb. 13. With the new 10 feet reflector I examined the neb. in Orion, and with long attention could just perceive my small faint nebula in the dark part of the great nebula.
1785, Oct. 5 (Sweep 458). The nebula in Orion. A wonderful phenomenon. One of the clearest nights I ever had.
1786, Nov. 28 (Sweep 640). The nebula in Orion which I saw by the front-view was so glaring and beautiful that I could not think of taking any place of its extent.
1799, Dec. 30, Review.(*) No. 43 of the Connoiss. [M43] is not visible in the finder but is the star north of No. 42. 10 feet, 300. The nebulosity about the star is not central and belongs probably to the rest of the nebulosity, the star being one of the scattered ones.

---

(*) [This and the following observations were not taken in the course of sweeps. - Ed. (Dreyer)]
1801, Jan. 14, Review. Large X [10] feet telescope, power 120. As before described. The nebulosity of the 43rd [M43] does not seem to belong to the star.
1806, Feb. 11, Review. Large 10 feet. The 4 stars are completely in the nebulosity. The 3 stars are entirely out of it with 270. With the double eyeglass, appearances are very different.
1810, Feb. 4, Review. 10 feet. The nebulosity is entirely of the milky kind and extends a great way. The 43rd [M43] is not a nebulous star, but a star happens to be situated in a place where some of the milky nebulosity of the great nebula happens to be. 1810, Dec. 31, Review. 10 feet, double eyepiece. The 4 stars are within the nebulosity. The star No. 7 (see the figure of Oct. 7, 1779) is upon the borders of the dark vacancy. I see No. 9 very well. The little star between 3 and 4 is still within very faint nebulosity. The nebulosity reaches beyond 4, as far as from 1 to 4 nearly. It touches a very small star and from that star goes on to two very bright ones, in the direction from the small star to the preceding one of the two. The black space near the four stars is much contracted. The nebulosity from 1 to 4 is concave, the concavity being to the following side. The parallel is nearly in the line 1 . 3 . 4. I can see eight different condensations notwithstanding the moon is very bright. The nebulous star is pretty equally involved, it has the appearance of a star shining through a very faint mist. The star is little larger than 4. The concavity from 2 to 7 goes beyond 7.
1811, Jan. 19, Review. 10 feet. Two of the four stars are within the nebulosity. No. 7 is very near the borders of the black. The little star between and following 3 and 4 is still within very faint nebulosity. The nebulosity reaches beyond 4 rather farther than form 1 to 4.
X feet. I perceive 7 or 8 different condensations. The place near the 4 stars is much contracted. The nebulous stars is exactly what we might expect to see if a star were to shine through whitish nebulosity.
40 feet. 5h 16' B. affected.(+)
[5h] 17 B. much affected.
[5h] 22 The 4 stars are entirely involved in nebulosity. The 7th and 9th stars are very bright.In the brightest part are four places brighter than the rest. I see the small detached nebula, it is extremely faint. It is between the corner and a small star. The star called nebulous is within a nebulosity nearly detached; but the small star marked nebulous in the figure of the 4th March 1774 (+) are free from nebulosity.There is a very small, nearly detached, nebulosity north of the nebulous star. The nebulous star has some resemblance tp a star shining through a very thin mist.
1811, Mar. 13, Review.(+) 7 feet, double eyepiece. The following or rather the south branch (for I find the parallel is nearly in the line 1 . 3 . 4) goes towards the preceding star e of the two large stars d e, or rather little preceding it, but it partly includes the star e and makes it appear a little nebulous. The light about the nebulous b is a little denser nearer the star than at a distance. A line from 5 through 7 goes to b or rather a little south of it; and 7 is about a 1/4 of the distance towards b. The star south of 3 and 4 makes an equilateral triangle with them. The two large stars d and e are parallel to 1 . 3 . 4 nearly. A line from the four stars parallel to 1 . 3 . 4 passes a little south of the small formerly nebulous star c. There are many other stars connected with the nebula which I do not notice.
1811, Mar. 15, Review. 7 feet, double eyepiece. The northern branch is parallel to the stars a b. The nebulosity reaches nearly up to the stars g h. A very faint nebulosity still joins the star b to the northern branch, but b is more nebulous than the intermediate nebulosity. The southern nebulosity goes towards the star e, and some part of the very faint nebulosity incloses the star.
1811, March 16, Review. 10 feet reflector, power 100. The stars 1.3 are in the parallel; 4 is a very little south of their parallel. The nebulosity about b is brightest about the star.

---

(+) [Compare Plate III fig. 37 and p. 489 (of SP2). - Ed. (Dreyer)]

M.43 [NGC 1982]

[WH 1786, p. 482; SP 1, p. ]
III.1. Nov. 3, 1783. [near 36 (Nu) Orionis]. vF. S. mE. In the L. neb.
Very faint. Small. Much extended. In the large nebula [M42].

[SP2, p. 298 (??)]
III.1 is an appendage to the north of M.43.

M.44 [NGC 2632]

[no WH observation reported]

M.45

[no WH observation reported]

M.46 [NGC 2437]

[SP2 p. 657]
1786, Mar. 19 (Sw. 540). A beautiful, very rich, compressed cluster of stars of various magnitudes.

M.47 [NGC 2422]

[WH 1786]
VIII.38. Feb. 4, 1785.
A Cl. of p. com. L. and S. st. R. above 15' d.
A cluster of pretty compressed large [bright] and small [faint] stars. Round. Above [more than] 15' diameter.

M.48 [NGC 2548]

[SP2 p. 657; Dreyer's remark: Not in NGC, 8h 7m, 91d 32' for 1860. This is not our modern M48 - hf]
1790, March 5 (Sweep 935). Looked for 48 of the Connoiss. des Temps but found that it does not exist in the place mentioned by Wollaston.
Mem. (*) I looked with the Sweeper for the 48th of the Conn., &c., and found a parcel of coarsely scattered stars , not deserving the name of a cluster; which on account of their being too far from each other could not be seen clustering in my 20 ft. Teles. They are scattered over a place near 2d in extent. [again, this is not M48 - hf]
(*: Dreyer's note: At the end of the same sweep)

[WH 1786. This is the modern M48 = NGC 2548 - hf]
H VI.22. Feb. 1, 1786.
A beautiful Cl. of much com. st. consid. rich. 10 or 12' dia. C.H. discovered it in 1783.
A beautiful Cluster of much compressed stars, considerably rich. 10 or 12' diameter. Caroline Herschel discovered it in 1783.

M.49 [NGC 4472]

[SP2 p. 657]
1785, Dec. 28 (Sw. 498). Very bright, considerably large, gradually much brighter in the middle, extended with faint branches. (*)
(*: Dreyer's note: This is the only observation being recorded as being of M.49. But see Vol. I [SP1] pp. 294-295, under I.7 and II.19.)

M.50 [NGC 2323]

[SP2 p. 657]
1785, March 4 (Sw. 377). A very brilliant cluster of large [bright] stars, considerably compressed and rich, above 20' in diameter, the stars of various sizes [magnitudes], visible in the finder.

M.51 [NGC 5194]

[SP2 p. 657]
1783, Sept. 17. 7 feet, 57. Two nebulae joined together; both suspected of being stars. Of the most north [H I.186, NGC 5195] I have hardly any doubt. 7 feet, about 150. A strong suspicion next to a certainty of being stars. I make no doubt the 20 ft. will resolve them clearly, as they want light and prevent my using a higher power with this instrument.
1783, Sept. 20. 20 ft., 200. Most difficult to resolve, yet I do no longer doubt it. In the southern nebula [NGC 5194] I saw several stars by various glimpses, in the northern [NGC 5195] also three or four in the thickest part of it, but never very distinctly. Evening very bad.
1787, May 12 (Sw. 734). Bright, a very uncommon object, nebulosity in the center with a nucleus surrounded by detached nebulosity in the form of a circle, of unequal brightness in three or four places, forming altogether a most curious object. [H] I.186 [NGC 5195] B. R. S. vgbM. [bright, round, small, very gradually brighter to the middle] just north of the former.
1788, April 29 (Sw. 836). vB. L. [very bright, large], surrounded with a beautiful glory of milky nebulosity with here and there small interruptions that seem to through the glory at a distance. [H] I.186 [NGC 5195] cB. pL., a little E. [considerably bright, pretty large, a little elongated], about 3' p. [preceding, W] Mess. 51 and about 2' more north. (*)
(*: Dreyer's note: These are the only observations recorded of the great spiral.)

M.51B [NGC 5195]

[WH 1789 p. 228, SP1 p. 339]
H I.186 (M51B = NGC 5195):
H I.186. May 12, 1787. cB. pL. R or lE. vgbM. 3' np. the 51st of the Conn.des Temps.
Considerably bright. Pretty Large. Round or little elongated. Very gradually brighter toward the middle. 3' north preceding [NW] of the 51st of the Connoissance des Temps [M51].

[SP2 p. 654]
1783, Sept. 17. 7 feet, 57. Two nebulae joined together; both suspected of being stars. Of the most north [H I.186, M51B (NGC 5195)] I have hardly any doubt. 7 feet, about 150. A strong suspicion next to a certainty of being stars. I make no doubt the 20 ft. will resolve them clearly, as they want light and prevent my using a higher power with this instrument.
1783, Sept. 20. 20 ft., 200. Most difficult to resolve, yet I do no longer doubt it. In the southern nebula [M51 (NGC 5194)] I saw several stars by various glimpses, in the northern [M51B (NGC 5195)] also three or four in the thickest part of it, but never very distinctly. Evening very bad.
1787, May 12 (Sw. 734). Bright, a very uncommon object, nebulosity in the center with a nucleus surrounded by detached nebulosity in the form of a circle, of unequal brightness in three or four places, forming altogether a most curious object. [H] I.186 [M51B (NGC 5195)] B. R. S. vgbM. [bright, round, small, very gradually brighter to the middle] just north of the former.
1788, April 29 (Sw. 836). vB. L. [very bright, large], surrounded with a beautiful glory of milky nebulosity with here and there small interruptions that seem to through the glory at a distance. [H] I.186 [M51B (NGC 5195)] cB. pL., a little E. [considerably bright, pretty large, a little elongated], about 3' p. [preceding, W] Mess. 51 and about 2' more north. (*)
(*: Dreyer's note: These are the only observations recorded of the great spiral.)

[1811: PT Vol. 1811, p. 226-336; here p. 285]
8. Of double Nebulae with joined Nebulosity In addition to the instances referred to in the preceding article [Of Nebulae which are brighter in more than one Place], of nebulae that have more than one centre of attraction I give the following list of what may be called double nebulae. (*) See [15 nebulae, including M51]

M.52 [NGC 7654]

[SP2 p. 657]
1783, Aug. 29. All resolved into innumerable small [faint] stars without any suspicion of nebulosity. 7 ft., 57. In the sweeper, 30, shews nebulosity, the stars being too obscure to be distinguished with its light tho' considerable.
1805, December 23, Review. Large 10 feet. This is a cluster of pretty condensed stars of different sizes [magnitudes]. It is situated in a very rich part of the heavens and can hardly be called insulated, it may only be a very condensed part of the Milky Way which is here much divided and scattered. It is however so far drawn together with some accumulation that it may be called a cluster of the third order.

M.53 [NGC 5024]

[WH 1784 p. 441, SP1 p. 159; WH 1814 p. 277, SP2 p. 537; WH 1818 p. 444, SP2 p. 598]
[WH 1784]
Again, No. 53 [of Messier's Catalog]. "Nébuleause sans étoiles, decouverte au-dessous et près de la chevalure de Bérénice, à peu de distance de l'étoile quarante-deuxieme de cette constellation, suivant Flamsteed. Cette nébuleuse est ronde et apparente &c. [Nebula without stars discovered below & near Coma Berenices, a little distant from the star 42 in that constellation, according to Flamsteed. This nebula is round and conspicuous, &c.]" My observation of the 170th Sweep runs thus: A cluster of very close stars; one of the most beautiful objects I remember to have seen in the heavens. The cluster appears under the form of a solid ball, consisting of small stars, quite compressed into one blaze of light, with a great number of loose ones surrounding it, and distinctly visible in the general mass. See fig. 2.

[WH 1814]
[Jan. 13, 1806?] 7 feet telescope, space penetrating power 20.25. "The 53d of the Connoiss [M 53 = NGC 5024] with 118 is easily resolvable, and some of the stars may be seen."
It will not be necessary to add that the two last mentioned globular clusters [M19 and M53], viewed with more powerful instruments, are of equal beauty with the rest; and from what has been said it is obvious that here the exertion of a clustering power has brought the accumulation and artificial construction of these wonderful celestial objects to the highest degree of mysterious perfection.

[WH 1818]
The 53rd of the Connoissance. [M 53 = NGC 5024]
"1813, 7 feet finder. It appears like a very small haziness."
"1783, 7 feet telescope. With 460 the object is extremely faint. 1813, with 118 it is easily resolvable, and some of the stars may be seen."
"1783, 10 feet telescope. With 250, I perceive 4 or 5 places that seem to consist of very small stars."
"1784, 1786, 20 feet telescope. A globular cluster of very compressed stars."
From the observation of the 7 feet telescope, it appears that the profundity of this cluster is of the 243d order.

M.54 [NGC 6715]

[SP2 p. 657]
1784, June 24 (Sw. 232). A round, resolvable nebula. Very bright in the middle and the brightness diminishing gradually, about 2 1/2' or 3' in diameter. 240 shews too pretty large [bright] stars in the faint part of the nebulosity, but I rather suppose them to have no connection with the nebula. I believe it to be no other than a miniature cluster of very compressed stars resembling that near the 42nd Comae [M53 - Dreyer]. It is like that under [south of] Delta Sagittarii [H I.50 = NGC 6624 - Dreyer], but rather larger and brighter tho' not much.
1784, July 13 (Sw. 237). A cL. vB. R. nebula, mbM. [A considerably large, very bright, round nebula, much brighter to the middle] and breaking off suddenly, the rest being much fainter.

M.55 [NGC 6809]

[WH 1818 p. 444, SP2 p. 599]
The 55th of the Connoissance. [M 55 = NGC 6809]
"1783, small 20 feet telescope. With 250 fairly resolved into stars; I can count a great many of them, while others are too close to be distinguished separately."
"1784, 1785, 20 feet telescope. A rich cluster of very compressed stars, irregularly round, about 8 minutes long."
By the obserevation of the small 20 feet telescope, which could reach stars 38.99 times as far as the eye, the profundity of this cluster cannot be much less than of the 467th order: I have taken it to be of the 400th order.

M.56 [NGC 6779]

[WH 1814 p. 275, SP2 p. 536; WH 1818 p. 444-445, SP2 p. 599]
[WH 1814]
January 5, 1807. 20 feet telescope. Space penetrating power 75.08. Magnifying power 157.3. "The 56th of the Connoiss. [M 56 = NGC 6779] is a globular cluster of very compressed and very small stars. They are gradually more compressed towards the centre."

[WH 1818]
The 56th of the Connoissance. [M 56 = NGC 6779]
"1783, 7 feet telescope. A strong suspicion of its being stars."
"1783, 1799, 10 feet telescope. 120 will not resolve it; 240 wants light: 350 however shows the stars, but they are so exceedingly close and small that they cannot be counted."
"1784, 1807, 20 feet telescope. A globular cluster of very compressed small stars about 4 or 5 minutes in diameter."
"1805, 1807, large 10 feet teelscope. With 171 it is 3' 36" in diameter."
The profundity of this cluster, by the observation of the 10 feet telescope, must be of the 344th order. It is near the preceding branch of the milky way.

M.57 [NGC 6720, annular in Lyra]

[WH 1785, p. 263, SP1 p. 257; WH 1814, p. 261, SP2 p. 527; WH 1818 p. 445, SP2 p. 599]
[1785]
A perforated Nebula, or Ring of Stars.
Among the curiosities of the heavens should be placed a nebula, that has a regular, concentric, dark spot in the middle, and is probably a Ring of stars. It is of an oval shape, the shorter axis being to the longer as about 83 to 100; so that, if the stars form a circle, its inclination to a line drawn from the sun to the center of this nebula must be about 56 degrees. The light is of the resolvable kind [i.e., mottled], and in the northern side three very faint stars may be seen, as also one or two in the southern part. The vertices of the longer axis seem less bright and not so well defined as the rest. There are several small stars very bear, but none seems to belong to it. It is the 57th of the Connoissance des Temps [Messier's catalog]. Fig. 5 is a representation of it.

[1814]
Connoiss. 57 [M 57 = NGC 6720] is "An oval nebula with an eccentric oval dark space in the middle; there is a strong suspicion of its consisting of stars. The diameter, measured by the large 10 feet, is 1'28".3."

[1818]
The 57th of the Connoissance. [M 57 = NGC 6720]
"1782, 7 feet telescope. I suspect it to consist of very small stars; in the middle it seems to be dark."
"1783, 1805, 1806, 10 feet telescope. With 130 it seems to be a rim of stars, but with 350 there remains a doubt. It is a little oval; the dark place in the middle is also oval; one side of the bright margin is a little narrower than the other."
"1784, 1799, 20 feet telescope. It is an oval with a dark place within; the light is resolvable. 240 showed several small stars near, but none that seems to belong to it. It is near 2 minutes in diamter."
"1805, large 10 feet telescope. By a meridian passage of 7 seconds of siderial time, the diameter is 1' 28".4."
By the observation with the 20 feet telescope, the profundity of the stars of which it probably consists must be of higher than 900th order; perhaps 950.

M.58 [NGC 4579]

[SP2 p. 658]
1784, March 15 (Sw. 174). pB. pL. [pretty bright, pretty large].
1784, April 17 (Sw. 199). L. F. [large, faint].

M.59 [NGC 4621]

[SP2 p. 658]
1784, April 17 (Sw. 199). pB. R., not S., mbM. [pretty bright, round, not small, much brighter to the middle].

M.60 [NGC 4649]

[SP2 p. 658]
1784, March 15 (Sw. 174). Two nebulae, one of them very bright.
1784, April 17 (Sw. 199). Two nebula, the p. vF. S. (III.44) [the preceding very faint, small (H III.44 = NGC 4647)], the following which is the 60th of the Conn. des Temps, B. cL. [bright, considerably large].

M.61 [NGC 4303]

[WH 1789 p. 227, SP1 p. ]
H I.139. April 17, 1785.
eB. vBN. r. 6 or 7' dia.
Extremely bright. Very bright nucleus. Resolvable [mottled, not resolved]. 6 or 7' diameter.

M.62 [NGC 6266]

[WH 1814 p. 279, SP2 p. 538; WH 1818 p. 446, SP2 p. 599]
[WH 1814]
Connoiss. 62 [M 62 = NGC 6266] is "Extremely bright, round, very gradually brighter in the middle, easily resolvable, about 4' in diameter. With 240 and strong attention I see the stars of it. It is a miniature of the 3rd of the Connoiss. [M 3]."

[WH 1818]
The 62nd of the Connoissance. [M 62 = NGC 6266]
"1783, 10 feet telescope. With 250, a strong suspicion, amounting almost to a certainty, of its consisiting of stars."
"1785, 1786, 20 feet telescope. Extremely bright, round, very gradually brighter in the middle, anout 4 or 5 minutes in diameter; 240 with strong attention showed the stars of it. The cluster is a miniature of the 3d of the Connoissance."
By the 20 feet telescope, which at the time of these observations was a Newtonian construction, the profundity of this cluster is of the 734th order. It is in the preceding branch of the milky way.

M.63 [NGC 5055]

[WH 1811, p. 310, SP2, p. 482; SP2 p. 658]
[1811]
Number 63 of the Connoissance des Temps is "A very bright nebula, extending from north-preceding to south-following 9 or 10' long, and near 4' broad; it has a very brilliant nucleus." Fig. 27.

[SP2]
1787, March 18 (Sw. 717). E. npsf. [Elongated north preceding (NW) to south following (SE)], 5 ot 6' long and near 4' broad, bright nucleus, very brilliant.
1787, April 9 (Sw. 725). vB. [Very bright], 9 or 10' long, considerably broad, the brightness confined to a small place.

M.64 [NGC 4826]

[SP2 p. 658]
1785, April 27 (Sw. 403). Extends not less than 25' and the southern branch loses itself more imperceptibly and is much broader and more diffused than the northern one; the night being very fine I viewed it to the great advantage. I suspected the ground of the heavens about the northern branch to be tinged with a very faint, milky nebulosity for a considerable way.
1787, Feb. 13 (Sw. 699). A very remarkable object, mE. [much elongated], about 12' long, 4' or 5' broad, contains one lucid spot like a star with a small black arch under it, so that it gives one the idea of what is called a black eye, arising from fighting.

M.65 [NGC 3623]

[WH 1811 p. 311, SP2 p. 483]
Number 65 of the Connoissance [M 65 = NGC 3623] is "A very brilliant nebula extended in the meridian, about 12' long. It has a bright nucleus, the light of which suddenly diminishes on its border, and two opposite very faint branches." Fig. 29.

M.66 [NGC 3627]

[SP2 p. 658]
1784, Apr. 12 (Sw. 188). A vB. mE. [very bright, much extended] nebula of irregular figure; the extension is chiefly in the direction of the meridian and the greatest brightness near the middle.

M.67 [NGC 2682]

[WH 1818 p. 446, SP2 p. 599]
The 67th of the Connoissance. [M 67 = NGC 2682]
"1783, 7 feet telescope. A cluster of stars."
"1809, 10 feet telescope. A cluster of vS. [very small] stars, there seems to be a F. [faint] milky nebulosity among them."
"1784, 20 feet telescope. A most beautiful cluster of stars; not less than 200 in view."
By estimation, the profundity of this cluster may be of the 144th order.

M.68 [NGC 4590]

[WH 1814 p. 273, SP2 p. 534; WH 1818 p. 446, SP2 p. 600]
[WH 1814]
Connoiss. 68 [M 68 = NGC 4590] is "A beautiful cluster of stars, extremely rich, and so compressed that most of the stars are blended together; it is near 3' broad and about 4' long, but chiefly round, and there are very few scattered stars about."
This oval cluster is also approaching to the globular form, and the central compression is carried to a high degree. The insulation is likewise so far advanced that it admits of an acurate description of the contour.

[WH 1818]
The 68th of the Connoissance. [M 68 = NGC 4590]
"1786, 1789, 1790, 20 feet telescope. A cluster of very compressed small stars, about 3 minutes broad and 4 minutes long. The stars are so compressed, that most of them are blended together."
Probably the stars of this cluster might be perceived by a 10 feet telescope, so that the profundity may be of the 344th order.

M.69 [NGC 6637]

[WH 1814 p. 280, SP2 p. 539; WH 1818 p. 447, SP2 p. 600]
[WH 1814]
I.51 [NGC 6638] and Connoiss. 69 [M69 = NGC 6637] are second miniatures of the 53rd [M 53].

[WH 1818]
The 69th of the Connoissance. [M 69 = NGC 6637]
"1784, 20 feet telescope. Very bright, pretty large, easily resolvable, or rather an already resolved cluster of minute stars. It is a miniature of the 53d of the Connoissance [M53]."
By this observation, the profundity of this cluster must be of the 734th order.

M.70 [NGC 6681]

[SP2 p. 658]
1784, July 13 (Sw. 237). er. cB. pL. iR. [extremely rich, considerably bright, pretty large, irregularly round]. A very faint red perceivable.

M.71 [NGC 6838]

[WH 1818 p. 447, SP2 p. 600]
The 71st of the Connoissance. [M 71 = NGC 6838]
"1794, 7 feet telescope. With 120 and 160 the stars of it become just visible."
"1783, 1899, 1810, 10 feet telescope. A cluster of stars of an irregular figure."
"1784, 1799, 1807, 20 feet telescope. It is situated in the milky way, and the stars are probably in the extent of it; it is however considerably condensed; about 3 minutes in diameter."
"1805, large 10 feet telescope. An irregular cluster of very small stars, 2'35" in diameter."
By the observation with the 7 feet telescope, the profundity of this cluster is of the 243d order. It is in the following branch of the milky way.

M.72 [NGC 6981]

[WH 1814 p. 274, SP2 p. 534; WH 1818 p. 447-448, SP2 p. 600; SP2 p. 658]
[WH 1814]
October 30, 1810. 40 feet telescope. Space penetrating power 191.68. Magnifying power 280. "Having been about 20 minutes at the telescope to prepare the eye properly for seeing minute objects, the 72d of the Connoiss. [M 72 = NGC 6981] came into the field. It is a very bright object."
"It is a cluster of stars of a round figure, but the very faint stars on the outside of globular clusters are generally a little dispersed so as to deviate from a perfectly circular form. The telescopes which have the greatest light shew this best."
"It is very gradually extremely condensed in the centre, bit with much attention, even there, the stars may be distinguished."
"There are many stars in the filed of view with it, but they are of several magnitudes totally different from the excessively small ones which compose the cluster."
"It is not possible to form an idea of the number of stars that may be in such a cluster; but I think we cannot estimate them by hundreds."
"The diameter of the cluster is about 1/5 of the field, which gives 1'53".6." See fig. 17.

[WH 1818]
The 72nd of the Connoissance. [M 72 = NGC 6981]
"1805, 7 feet telescope. With a power of 80 the stars may just be perceived."
"1783, 1810, 10 feet telescope. With 150 fairly resolved."
"1784, 1788, 20 feet telescope. A cluster of very small stars."
"1810, large 10 feet telescope. A globular cluster; its diameter is 2' 40"."
"1810, Oct. 30, 40 feet telescope. A beautiful cluster of stars." [For further particulars see above, 1814]
By the observation with the 7 feet telescope, the profundity of this cluster must be of the 243d order.

[SP2 p. 659]
1810, Oct 30, Review. 40 feet. Having been about 20 minutes at the telescope to prepare the eye properly for seeing critical objects, the 72nd of the Connois. came into the field. It is a very bright object. It is a cluster of stars of a round figure, but the very faint stars on the outside of these sorts of clusters are generally a little dispersed so as to deviate from a very perfect circular form; the telescopes which have the greatest light shew this best. It is very gradually extremely condensed in the center, but with much attention even there the stars may be distinguished. Power 280. There are many stars in the field of view with it, butthey are of many magnitudes and totally different from the excessively small [faint] ones which compose the cluster. It is not possible to form an idea of the number of stars that may be in such a cluster, but I think we cannot estimate them by hundreds. The diameter is about 1/5 of the field = 1' 53.6". - 10 feet telescope. I viewed the same object. The contrast is very striking, it appear eF [extremely faint].

M.73 [NGC 6994]

[SP2 p. 658]
1783, Sept. 28. Consists of a few stars arranged in triangular form. No nebulosity among them. 10 ft., 150.

M.74 [NGC 628]

[WH 1800 p. 70, SP2 p. 43; WH 1818 p. 448, SP2 p. 600]
[WH 1800]
Sept. 20, 1783, I viewed the nebula between Flamsteed's 99th and 105th Piscium, discovered by Mr. Mechain, in 1870. [M 74 = NGC 628]
"It is not visible in the finder of my 7-feet telescope; but that of my 20-feet shews it."
Oct. 28, 1784, I viewed the same object with the 7-feet telescope.
"It is extemely faint. With a magnifying power of 120, it seems to be a collection of very small stars: I see many of them."

[WH 1818]
The 74th of the Connoissance. [M 74 = NGC 628]
"1783, 1784, 7 feet telescope. With 100 and 120 it its a collection of very small stars; I see many of them."
"1799, 1801, 10 feet telescope. Several of the stars are visible; it is a very faint objects."
"1784, 20 feet telescope. Some stars are visible in it; the edges are not resolvable."
"1805, 1810, large 10 feet telescope. With 108 it consists of extremely small stars, of an irregular figure; a very faint object of nearly 12 minutes diameter."
"1799, December 28, 40 feet telescope. Very bright in the middle, but the brightness confined to a very small part, and is not round; about the bright middle is a very faint nebulosity to a considerable extent. The bright part seems to be of resolvable kind, but my mirror has been injured by condensed vapours."
By the observations of the 7 feet telescope, the profundity of the nearest part of this cluster must be of the 243d order, but most probably a susscession of more distant stars was seen in the larger telescopes.

M.75 [NGC 6864]

[WH 1814 p. 279, SP2 p. 538; WH 1818 p. 448-449, SP2 p. 600]
[WH 1814]
Connoiss. 75 [M 75 = NGC 6864] is "A globular cluster of stars, and is a miniature of the third [M 3]."

[WH 1818]
The 75th of the Connoissance. [M 75 = NGC 6864]
"1799, 7 feet finder. It is just but visible."
"1799, 7 feet telescope. There is not the least appearance of its consisting of stars, but it resembles other clusters of this kind, when they are seen with low space-penetrating and magnifying powers."
"1810, 10 feet telescope. With 71 it is small and cometic."
"1784, 1785, 20 feet Newtonian. Easily resolvable; some of the stars are visible."
"1810, 20 feet, front view. It is a globular cluster."
"1799, 1810, large 10 feet. Its diameter with 171 is 1' 48"; with 220 it is 2' 0"."
By the observation of the 20 feet Newtonian telescope, the profundity of this cluster must be of the 743d order.

M.76 [NGC 650-1]

[SP2 p. 659]
1787, Nov. 12 (Sw. 780). Two close together, their nebulosities run into each other; distance of their centers is 1 1/2 or 2' [M76 and H I.193]. [actually, the whole object is M76]

M.77 [NGC 1068]

[WH 1818 p. 449, SP2 p. 601]
The 77th of the Connoissance. [M 77 = NGC 1068]
"1783, 7 feet telescope. An ill defined star, surrounded by nebulosity."
"1801, 1805, 1809, 1810, 10 feet telescope. It has almost the appearance of a large stellar nebula."
"1783, 1785, 1786, 20 feet telescope. Bery bright; an irregular extended nucleus with milky chevelure, 3 or 4 minutes long, near 3 minutes broad."
"1801, 1805, 1807, large 10 feet telescope. A kind of much magnified stellar cluster; it contains some bright stars in the centre. With 171 its diameter is 1' 17"; with 220 it is 1' 36"."
From the observations of the large 10 feet telescope, which has a gaging power of 75.82, we may conclude that the profundity of the nearest part of this object is at least of the 910th order.

M.78 [NGC 2068]

[SP2 p. 659]
1783, Dec. 19 (Sw. 59). Two large [bright] stars, well defined, within a nebulous glare of light resembling that in Orion's sword. There are also three very small [faint] stars just visible in the nebulous part which seem to be component particles thereof. I think there is a faint ray near 1/2 deg long towards the east and another towards the south east less extended, but I am not quite so well assured of the reality of these latter phenomena as I could wish, and would rather ascribe them to some deception. At least I shall suspend my judgement till I have seen it again in very fine weather, tho' the night is far from bad.
1786, Jan. 1 (Sw. 506). Very large milky nebulosity, terminating suddenly on the north side; contains 2 pL. [pretty large (bright)] stars, they are on the north side.
1786, Dec. 22 (Sw. 661). Milky nebulosity containing three stars, iF. [irregularly formed], 5 or 6' long.

M.79 [NGC 1904]

[WH 1814 p. 276-277, SP2 p. 537; WH 1818 p. 449-450, SP2 p. 601]
[WH 1814] Jan. 13, 1806. Large 10 feet. "The 79th of the Connoiss. [M 79 = NGC 1904] is a cluster of stars of a globular construction, and certainly extremely rich. Towards the centre the stars are extremely compressed, and even a good way from it. With 171 the diameter is a little less than 1/3 of the field, and with 220 a little more; the field of one being 9'0", and of the other 8'0", a mean of both gives the diameter of the cluster 2'50", but I suppose that the lowness of the situation prevents my seeing the tiny scattered stars, so that this cluster is probably larger than it appears." (*)

---

(*) The large 10 feet telescope is in a considerable degree subject to the obstructions arising from change of temperature, and tarnish; but as it can be directed to any part of the heavensin a few minutes, and is easily prepared for observation, it becomes a very useful instrument when the clearness of the atmosphere is interrupted by flying clouds; ot when the place of an object is not visible in the finder, or night glass, is to be ascertained.

[WH 1818] The 79th of the Connoissance. [M 79 = NGC 1904]
"1783, 7 feet telescope. With 57 nebulous, with 86 strong suspicion of its being stars."
"1799, 10 feet telescope. 300 shows the stars of it with difficulty."
"1784, 20 feet telescope. A beautiful cluster of stars, nearly 3 minutes in diameter."
"1806, large 10 feet telescope. A globulat cluster, the stars of which are extremely compressed in the middle; with 171 and 220 the diameter is 2 '50", but the lowness of the situation probably prevents my seeing the whole of its extent."
By the observation of the 10 feet telescope the profundity of this cluster is of the 344th order.

M.80 [NGC 6093]

[WH 1814 p. 275, SP2 p. 536; WH 1818 p. 450, SP2 p. 601]
[WH 1814]
May 26, 1786. 20 feet telescope. "The 80th of the Connoiss. [M 80 = NGC 6093] is a beautiful, round cluster of extremely minute and very compressed stars about 3 or 4' in diameter; by the increasing compression of the stars the cluster is very gradually very much brighter in the middle."

[WH 1818]
The 80th of the Connoissance. [M 80 = NGC 6093]
"1784, 1786, 20 feet telescope. A globular cluster of extremely minute and very compressed stars of about 3 or 4 minutes in diameter; very gradually much brighter in the middle; towards the circumference the stars are distinctly seen, and are the smallest imaginable."
The profundity of this cluster is probably not much less than the 734th order.

M.81 [NGC 3031]

[SP2 p. 659]
1801, Nov. 8 (Sw. 1100). eB [extremely bright], the bright part confined to a very small place; the nebulosity is of the milky kins, vm. E. npsf. [very much extended north preceding (NW) to south following (SE)].
1802, Sept. 30 (Sw. 1112). vB. eL. [very bright, extremely large]; it very nearly fills all the field, it loses itself imperceptibly, m. E. npsf. [much extended north preceding (NW) to south following (SE)]; I can trace it nearly 1/2 deg in extent beyond the bright part.
1810, Nov. 26, Review. I viewed the nebula with the large 10 feet. It has a bright, resolvable nucleus, certainly coonsisting either of 3 or 4 stars or something resembling them. It is about 15 or 16' long. The object was already too low to be seen to an advantage.

M.82 [NGC 3034]

[SP2 p. 659]
1801, Nov. 8 (Sw. 1100). eB. m.E. spnf. [extremly bright, much extended south preceding (SW) to north following (NE)], about 10' long.
1802, Sept. 30 (Sw. 1112). A vB. [very bright], beautiful ray of light, brightest in the middle of all the length, about 8' long, 2 or 3' broad. (*)
(*) Dreyer's note: Entered the Cape Observations, p. 128, as a new nebula, IV.79. [John Herschel's error - hf]
1810, Nov. 26, Review. Viewed with the large 10 feet. It is mottled in its length as acontaining 5 or 6 vS. [very small (faint)] stars affected with nebulosity. With No. I about 1/5 of the field or less, about 6 or 7' in length; the breadth is about 1 1/2 or 1 3/4, the object is too low.

M.83 [NGC 5236]

[SP2 p. 659]
1787, March 15 (Sw. 711). vB. [very bright], a B. [bright] resolvable nucleus in the middle with F. [faint] branches about 5' or 6' long, E. spnf. [extended south preceding (SW) to north following (NE)].
1793 May 5 (Sw. 1041). vB. [very bright], s SBN [suddenly brighter nucleus] with very extensive and vF. [very faint] nebulosity; it more than fills the field, it seems to be rather stronger from sp. [south preceding, SW] to nf. [north following, NE]. It may be ranked among the nebulous stars.

M.84 [NGC 4374]

[SP2 p. 659]
1784, Apr. 17 (Sw. 199). A bright nebula. [The only observation - Dreyer]

M.85 [NGC 4382]

[SP2 p. 659]
1784, Mar. 14 (Sw. 170). Two resolvable nebulae; the precedint [Western] is the largest, and with 157 seems to have another small nebula joined to it, but with 240 it appears to be a star. The following neb. is II.55 [NGC 4394].

M.86 [NGC 4406]

[SP2 p. 659]
1784, Apr. 8 (Sw. 187). Two resolvable nebulae at 4' or 5' distance. (*)
[(*) Dreyer's note: In the sweep they are 3.0m p. [W] and 1d 16' s [S] of M88. They are therefore II.121 and 122 [NGCs 4458 and 4461). H. [W. Herschel] took them for M. 86 and another which he called I.28. The comparison of I.28 with 34 Virginis was not made in this sweep but in Sw. 199.]
1784, April 17 (Sw. 199). Two B. cL. nebulae. One is the 86th of the Connoiss., the other is I.28.

M.87 [NGC 4486]

[SP2 p. 660]
1784, Apr. 12 (SW. 189). Two S.F. [small, faint) and one L.B. (large, bright) nebula, the two first like the p. [preceding, Western] two [i.e. II.121, 122 (NGCs 4485 and 4461)], the B. [bright] one R. mbM. [round, much brighter to the middle].
1784, Apr. 17 (SW. 199). Three nebulae, the two first vF. S. [very faint, small], the third L. B. mbM. [large, brighte, much brighter to the middle], but diminishing very gradually in brightness. The two first are II.123, 124 [NGCs 4476, 4478].

M.88 [NGC 4501]

[SP2 p. 660]
1784, Apr. 8 (Sw. 187). B. pL. r. [bright, pretty large, round] with a S. [small] one after it; moon light so strong that I had nearly overlooked the latter. (*)
[(*) Dreyer's note: See SP1, p. 297, note to II.118]
1787, Jan. 14 (Sw. 691). vB. vL. E. [very bright, very large, extended].

M.89 [NGC 4552]

[SP2 p. 660]
1784 Apr. 17 (Sw. 199). B. pS. [bright, pretty small].

M.90 [NGC 4569]

[SP2 p. 660]
1784. Apr. 8 (Sw. 187). pL. [pretty large], with a nucleus, perhaps cometic, but moonlight permits not to give a proper description.
1784. Apr. 17 (Sw. 199). pL. [pretty large].

M.91 [NGC 4548]

[WH 1786]
II.120. April 8, 1784.
L. r.
Large. Round.

[WH 1789]
JH's M91 candidate, H III.602 [NGC 4571]
H III.602. January 14, 1787.
vF. cL. vgbM. s. cBst.
Very faint. Considerably large. Very gradually brighter toward the middle. South of it is a considerably bright star.

M.92 [NGC 6341]

[WH 1818 p. 450-451, SP2 p. 601]
The 92nd of the Connoissance des Temps. [M 92 = NGC 6341]
"1799, 7 feet finder. It may just be distinguished; it is but little larger than a star."
"1783, 2 feet sweeper. With 15 it appears like a clouded star."
"1783, 7 feet telescope.With 227 resolves into very small stars; with 460 I can count many of them."
"1799, 10 feet telescope. With 240 the stars are much condensed at the centre."
"1783, 1787, 1799, 20 feet telescope. A brilliant cluster, 6 or 7 minutes in diameter."
"1805, large 10 feet telescope. The most condensed part is 3'16" in diameter."
The profundity of this cluster, by the observation with the 7 feet telescope, is of the 243rd order.

M.93 [NGC 2447]

[SP2 p. 660]
1784, Nov. 20 (Sw. 326). A cluster of scattered stars, pretty close and nearly of a size [same magnitude], the densest part is about 15' diam.[eter], but the rest very extensive.

M.94 [NGC 4736]

[SP2 p. 660]
1787, March 18 (Sw. 717). Very brilliant, a large, luminous nucleus of more than 20" diameter with faint chevalure and branches extending 6 or 8'.
1787, Apr. 9 (Sw. 725). Very brilliant, with much F. [faint] nebulosity on the sp. [south predecing, SW] and more on the f. [following, E] side.

M.95 [NGC 3351]

[SP2 p. 660]
1784. March 11 (Sw. 164). A fine, bright nebula, much brighter in the middle than at the extremes, of a pretty considerable extent, perhaps 3 or 4' or more. The middle seems to be of the magnitude of 3 or 4 stars joined together, but not exactly round; from the brightest part of it there is a sudden transition to the nebulous part, so that I should call it cometic.

M.96 [NGC 3368]

[SP2 p. 660]
1784. Mar. 11 (Sw. 164). A fine, bright nebula, much like the former [M95], but the brightest part in the middle is more jopined to the nebulosity than in the former, and the bright part is rather longer, tho' not quite so vivid as in the former. It may still be called cometic, tho' it begins to depart a little from that kind.

M.97 [NGC 3587]

[WH 1811 p. 314, SP2 p. 485; WH 1818 p. 451, SP2 p. 601]
[WH 1811]
Number 97 of the Connoissance is "A very bright, round nebula of about 3' in diameter; it is nearly of equal light throughout, with an ill defined margin of no great extent."

[WH 1818]
The 97th of the Connoissance. [M 97 = NGC 3587]
"1799, 7 feet finder. The object is not visible in it."
"1789, 20 feet telescope; considerably bright, globular, of equal light throughout, with a diminishing border of no great extent. About 3 minutes in diameter."
"1805, large 10 feet telescope. The constellation being too low it had the appearance of a faint nebula."
From the observation with the 20 feet telescope, it appears that the profundity of this object is beyond the gauging power of that instrument; and as it must be sufficiently distant to be ambiguos, it cannot be less than of the 980th order.

M.98 [NGC 4192]

[WH 1784 p. 441, SP1 p. ; SP2 p. 660]
[1784]
December 30, 1783. "A large, extended fine nebula."
The difference [of Messier's and Mechain's observations on one hand, and Herschel's on the other] will appear when we compare my observation of the 98th nebula with that in the Connoissance des Temps for 1784, which runs thus: [Messier's description follows in French; for a translation, see e.g. here]. My observation of the 30th December, 1783, is thus: A large, extended fine nebula. Its situation shews it to be M. Messier's 98th; but from its description it appears, that that gentleman has not seen the whole of it, for its feeble branches extend above a quarter of a degree, or which no notice is taken. Near the middle of it are a few stars visible, and more suspected. My field of view will not quite take in the whole nebula. See fig. 1 of tab. XVII.

[SP2]
1787, Jan. 14 (Sw. 691). vB. mE. [very bright, much extended], over 15' long, a BN [bright nucleus] in the middle.

M.99 [NGC 4254]

[SP2 p. 660]
1787, Jan. 14 (Sw. 691). vB. vL. vgmbM. [very bright, very large, very gradually much brighter to the middle], and the brightness taking up a great space.

M.100 [NGC 4321]

[WH 1814 p. 262, SP2 p. 528 (one observation)]
Connoiss. 100 is "A nebula of about 10' in diameter, but there is in the middle of it, a small, bright cluster of supposed stars."

M.101 [NGC 5457]

[SP2 p. 660]
1783, Sept. 20. 20 feet, 200. 20 feet, 200. In the northern part is a large [bright] star pretty distinctly seen, and in the southern I saw 5 or 6 small [faint] ones glitter through the greatest nebulosity which appears to consist of stars. Evening bad. This and the 51st [M51] are both so far removed from the appearance of stars that it is the next step to not being able to resolve them. My new 20 feet will probably render it easy.
1789, April 14 (Sw. 921). vB. SN. [very bright, small nucleus] with extensive nebulosity, pretty well determined on the preceding [W] side, but very diffuse to the north following [NE]. Includes the two following nebulae [III.788 and 789, NGCs 5461, 5462], and seems to extend 20', perhaps 30' or more.

M.102 [NGC 5866]

[WH 1789 p. 229, SP1 p. 340]
I.215. May 5, 1788. vB. cL. E. f. 2 st.
Very bright. Considerably large. Extended [elongated]. Following [lying east of] 2 stars.

M.103 [NGC 581]

[SP2 p. 660]
1783, Aug. 8. 14 or 16 pL. [pretty large (bright)] stars with a great many eS. [extremely small (faint)] ones. Two of the large [bright] ones are double, one of the 1st the other of the 2nd class. (*) The compound eye glass shews a few more that may be taken into the cluster so as to make them about 20. I exclude a good many straggling ones, otherwise there would be no knowing where to stop.
[(*) Dreyer's note: Neither was cataloged by H. [W. Herschel]. One is Struve 131.]

M.104 [NGC 4594]

[WH 1786, p. 472, SP1 p. ]
I.43. May 9, 1784. E. vBM. 5 or 6' l.
Extended [elongated]. Very bright toward the middle. 5 or 6' long.

[From: Notes to Sir W. Herschel's First Catalogue of Nebulae and Clusters, by J.L.E. Dreyer, in: Scientific Papers, Vol. 2, p. 295]
Second obs., Sw. 819, Mar. 11, 1788. mE, from about 20d sp. to nf., BN., 4 or 5' long, 49 Virg. p. 27m 45s s. 0d 51'. In 1784 "the B. place in the middle is pL., but breaks off abruptly."
Second observation, Sweep 819, Mar. 11, 1788. Much elongated, from about 20d south preceding [SW] to north following [NE], brighter toward the nucleus, 4 or 5' long, 49 Virg. preceding [W] 27m 45s, south 0d 51'. In 1784 "the bright place in the middle is pretty large, but breaks off abruptly."

M.105 [NGC 3379]

[WH 1786 p. 472, SP1 p. ]
I.17. Mar. 11, 1784. [Together with I.18 = NGC 3384] The 2 p of 3. Both vB. cL. mbM. C. II 41. Fig. 4.
The 2 preceding of 3. Both very bright. Considerably large. Much brighter toward the middle. Compare H II.41 [NGC 3389]. Figure 4.

M.106 [NGC 4258]

[WH 1789 p. 250, SP1 p. ]
V.43. March 9, 1788.
v brilliant. BN. with Fm. bran. np sf. 15' l. and to the sf. running into vF. nebulosity extending a great way. the N. is not R.
Very brilliant. Bright Nucleus. With faint milky branches north preceding and south following. 15' long and to the south following running into very faint nebulosity extending a great way. The nucleus is not round.

M.107 [NGC 6171]

[WH 1802 p. 526, SP2 p. ]
VI.40. May 12, 1793.
A very beautiful e com. cl. of st. extremely rich, 5 or 6' in diam. gradually more compressed toward the centre.
A very beautiful extremly compressed cluster of stars, extremely rich, 5 or 6' in diameter, gradually more compressed toward the centre.

M.108 [NGC 3556]

[WH 1802 p. 524, SP2 p. 231; WH 1814 p. 249, SP2 p. 520]
V.46. Apr. 17, 1789.
vB. mE. r. 10' l, 2' b. There is an unconnected pretty bright star in the middle.
Very bright. Much extended [elongated]. Resolvable [mottled, not resolved]. 10' long, 2' broad. There is an unconnected pretty bright star in the middle.

[WH 1814]
V.46 [NGC 3556 = M 108] is "A pretty bright star in the middle of a very bright nebula, about 10 minutes in length and 2' broad."

M.109 [NGC 3992]

[WH 1802 p. 520, SP2 p. 228]
IV.61. Apr. 12, 1786.
cB. BrN with vFE branches about 30deg np sf. 7 or 8' l, 4 or 5' b.
Considerably bright. Bright resolvable [mottled, not resolved] nucleus with very faint extended branches to position angle 30deg north preceding to south following. 7 or 8' long, 4 or 5' broad.

M.109B [NGC 3953]

[WH 1802 p. 524, SP2 p. 231]
V.45. Apr. 12, 1789.
cB. iF. E. mer. LBN. with F. branches 7 or 8' l, 5 or 6' b.
Considerably bright. Irregularly formed. Extended meridionally [along the Meridian, i.e. North-South]. Little brighter Nucleus. With faint brances 7 or 8' long, and 5 or 6' broad.

M.110 [NGC 205]

[WH 1786 p. 494, SP1 p. ]
V.18. Oct. 5, 1784.
vB. mE. 30'l. 12. b. C.H.
Very bright, much extended, 30' long, 12' broad, discovered by Caroline Herschel.

• J.L.E. Dreyer, 1912. Unpublished Observations of Messier's Nebulae and Star Clusters. Appendix I of The Scientific Papers of Sir William Herschel, Vol. II (SP2), p. 651-660.
• J.L.E. Dreyer, 1912. The Scientific Papers of Sir William Herschel, Volume I and Volume II. Royal Society and Royal Astronomical Society, London.
• William Herschel, 1784. Account of some Observations tending to investigate the Construction of the Heavens. Philosophical Transactions of the Royal Society of London, Vol. LXXIV (74), p. 437-451. Reprinted in: SP1, p. 157-166.
• William Herschel, 1785. On the Construction of the Heavens. Philosophical Transactions of the Royal Society of London, Vol. LXXV (75), p. 213-266. Reprinted in: SP1, p. .
• William Herschel, 1786. Catalogue of One Thousand new Nebulae and Clusters of Stars. Phil. Trans., Vol. LXXVI (76), p. 457-499. Reprinted in SP1, p. 260-294.
• William Herschel, 1789. Catalogue of a second Thousand of new Nebulae and Clusters of Stars; with a few introductory Remarks on the Construction of the Heavens. Philosophical Transactions of the Royal Society of London, Vol. LXXIX (79), p. 212-255. Reprinted in SP1, p. .
• William Herschel, 1800. On the penetrating into Space by Telescopes; with a comparative Determination of the Extent of that Power in natural Vision, and in Telescopes of various Sizes and Construction; illustrated by select Observations. Read November 21, 1799. Philosophical Transactions of the Royal Society of London, Vol. XC (90), p. 49-85. Reprinted in: SP2, p. 31-52.
• William Herschel, 1802. Catalogue of 500 new Nebulae, nebulous Stars, planetary Nebulae, and Clusters of Stars; with Remarks on the Construction of the Heavens. Philosophical Transactions of the Royal Society of London, Vol. XCII (92), p. 477-528. Reprinted in: SP2, p. .
• William Herschel, 1811. Astronomical Observations relating to the Construction of the Heavens, arranged for the Purpose of a critical Examination, the Result of which appears to throw some new Light upon the Organization of the celestial Bodies. By William Herschel, LL.D.F.R.S. Read June 20, 1811. Philosophical Transactions of the Royal Society of London, Vol. CI (101), p. 269-336. Reprinted in SP2, p. 459-497..
• William Herschel, 1814. Astronomical Observations relating to the siderial part of the Heavens, and its Connection with the nbulous part; arranged for the purpose of a critical Examination. Philosophical Transactions of the Royal Society of London, Vol. CIV (104), p. 248-284. Reprinted in SP2, p. 520-541.
• William Herschel, 1818. Astronomical observations and experiments, selected for the purpose of ascertaining the relative distances of clusters of stars, and of investigating how far the power of our telescopes may be expected to reach into space, when directred to ambiguous celestial objects. By Sir William Herschel, Knt. Guelp, LL.D.F.R.S. Read June 11, 1818. Philosophical Transactions of the Royal Society of London, Vol. CVIII (108), p. 429-470. Reprinted in SP2, p. 592-613.

Last Modification: February 19, 2005