relating to the Construction of the Heavens . 313 
IV. 23 is “ A considerably bright nebula with a very bright 
nucleus, and a chevelure about 3 or 4/ in diameter.” Fig. 31. 
III. gg is “ A small nebula with a pretty bright nucleus and 
M very faint chevelure ; it is almost like a nebulous star.” 
Fig. 32. 
The chevelure of these nebulae consists probably of the 
rarest nebulous matter, which not having as yet been consoli- 
dated with the rest, remains expanded about the nucleus in 
the shape of a very extended atmosphere; or it may be of an 
elastic nature, and be kept from uniting with the nucleus, as 
their elasticity causes the atmospheres of the planets to be ex- 
panded about them. In this case we have another property 
of the nebulous substance to add to the former qualities of its 
matter. 
With those nebulae where this chevelure is uncommonly 
faint, and the nucleus very bright, the consolidation appears to 
have reached a still higher degree, and their resemblance to 
nebulous stars may lead to very interesting consequences. 
28. Of round Nebula that are of an almost uniform Light. 
The argument that the nebulous matter is in some degree 
opaque which is given in the 25th article, will receive consi- 
siderable support from the appearance of the following ne- 
bulae ; for they are not only round, that is to say the nebulous 
matter of which they are composed is collected into a glo- 
bular compass, but they are also of a light which is nearly of 
an uniform intensity except just on the borders. I give these 
nebulae in two assortments.* 
* See Four from 2' to 4' in diameter. IV. 50, 6z, 67. Connoiss. 97. 
Twelve nebula; from % of a minute to 2' in diameter. I. 267. II. 186,209, 705, 
836, 870. III. 152, 877. IV. 13, 14, 16, 39. 
MDCCCXI. S S 
