A. Clark on the Sun and Stars photometrically compared. 79 
The vast number of smaller, or more moderate lights, like our 
sun, which may remain concealed among those of extraordinary 
splendor, yet so remote as only just sensibly to impress our vis- 
ion when aided to the utmost that human skill can do, will be 
better understood when we consider the ratio in which an in- 
crease of radius increases the cubic contents of a sphere. 
Upon the outer limits of such a sphere as would embrace the 
great mass of telescopic stars, a moderate depth, extended round 
the whole, would afford an immense amount of room for stars of 
all imaginable sizes. I desire to be particularly understood, that 
close by ¥ ety Brae in tabular oem: my own aida te 
those published by Mr. Bond of the Satine College Once 
tory, and by Dr. TW llaston, in vol. exix of the Philosophical 
Transactions of the Royal Society of rae of comparisons be- 
tween the bright star « Lyre and the 
To bring the magnitude of our sun a an equality with that of 
this star, his distance would roan to be in according to 
Wollaston, nearly - - 425,000 times. 
Bond, - - - - - 155,000 
Clark, : : 102,000 “ 
The light received from — luminaries differs, according to 
Wollaston, as . : ‘ - 180, 00,000,000 to 
ik ee  y0400,000000 . * 
IT have alluded to ‘the light in (abe atmosphere about the sun, 
as giving an increase to his photometrical force; though I am 
aware that such must be the case with a star; and it must bear 
: the same proportion to the star’s-light, that it ‘pears to the sun's 
ht. 
The difference, in effect, is here; we have several thousand 
Stars playing into our atmosphere at ‘once; but only one sun. 
If the distances imputed to several of the stars, from parallax, 
_ can be true, I am sure, those having the taste, talent, and leisure, 
— for following up photometrical researches with effi- 
