438 Mr. Herscuer’s Obferustions on 
interior confitruétion of the heavens, and its various mebulaus and 
fidereal frata (to borrow a term from the natural hiftorian) of 
which this paper can as yet only give a few outlines, or rather » 
hints. Asan apology, however, for this prematurity, it may 
be faid, that the end of all difcoveries being communication, 
we can never be too ready in giving facts and obfervations, 
whatever we may be in reafoning upon them. 
Hitherto the fidereal heavens have, not inadequately for the 
purpofe defigned, been repretented by the concave furface of a 
{phere, in the center of which the eye of an obferver might 
be {uppofed to be placed. It is true, the various magnitudes 
of the fixed ftars even then plainly fuggefted to us, and would 
have better fuited the idea of an expanded firmament of three 
dimenfions ; but the obfervations upon which Iam now gomg 
to enter ftill farther illuftrate and enforce the neceflity of con- 
fidering the heavens in this point of view. [fn future, there- 
fore, we fhall look upon thofe regions into which we may 
now penetrate by means of fuch large telefcopes, as a natu- 
ralift regards a rich extent of ground or chain of mountains, 
containing {trata varioufly inclined and direéted, as well as 
confifting of very different matetials. A furface of-a globe or 
map, therefore, will but ill delineate the interior parts of the 
heavens. 
It may well be expected, that the great advantage of alarge 
aperture would be moft fenfibly perceived with all thofe objeéts 
that require much light, fuch as the very fmall and immenfely 
diftant fixed ftars, the very faint nebula, the clofeand com- 
prefled clufters of ftars, and the remote planets. | 
On applying the telefcope to a part of the v/a /actea, I found’ 
that it completely refolved the whole whitifh appearance into 
{mall ftars, which my former telefcopes had not light enough 
3 to 
