26o Dr, Herschel’s Astronomical Observations 
and of a milky appearance, which will decide it to be purely 
nebulous. 
But when an object is of such a construction, or at such a 
distance from us, that the highest power of penetration, which 
hitherto has been applied to it, leaves it undetermined whether 
it belong to the class of nebulee or of stars, it may then be 
called ambiguous. As there is, however, a considerable dif- 
ference in the ambiguity of such objects, I have arranged 71 
of them into the following four collections.* 
The first contains seven objects that may be supposed to 
consist of stars, but where the observations hitherto made, of 
either their appearance or form, leave it undecided into which 
class they should be placed. 
Connoiss. 31 is “ A large nucleus with very extensive ne- 
“ bilious branches, but the nucleus is very gradually joined to 
“ them. The stars which are scattered over it appear to be be- 
“ hind 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 this aperture, seemed to be more milky.'' 
* See seventy-one ambiguous objects, in four collections. 
First collection II, 400. Ill, 379. 693. 745. V, 2. Connoiss. i. 31. 
Second collection I, 46. 50. II, 27. 78. 79. 180. 195. 199. 207. 554. 609. 771. 822. 
850. 855. Ill, 3. loi. 239. 399. 455. 696. 725. 743. IV, 22. Connoiss. 57. 70. 
Third collection I, 44. 47. II. 47. 48. 76. 105. 202. 279. 283. 469. 473. 500. 608. 
S08. 111,47.53.55.134.288.580.747.910. V, I. VI, 38. Connoiss. 81. 82. 
Fou.-th collection I, 52. 103. 122. 249. 288. II, 4. 84. 584. V, 3. VI, 15, 20. 
Connoiss. 100. 
