44 Mr. Micuexy on the Means of difcovering the 
20. As the {quares of the periodical times of bodies, revolv- 
ing round a central body, are always proportional to the cubes 
of their mean diftances, the diftance of the two bodies from 
each other mutt therefore, upon the foregoing fuppofitions, be 
fixteen times greater in proportion to the diameter of the’ central 
body, than the diftance of the earth from the fun in proportion 
to his diameter; and that diameter being already found to be 
alfo greater than that of the fun in the proportion of 155,2 tor, 
this diftance will confequently be greater than that of the earth 
and fun‘ from each other in the proportion of 16 times 155,2, 
that is 2483,2 tor. | 
21. Let us farther fuppofe, that from the obfervations, the 
greateft diftance of the two ftars in queftion appeared to be 
only one fecond;’ we muft then multiply the number 2483,2 
by 206.264,8, the number of feconds in the radius of a circle, 
and the produét 512.196.7509 will fhew the number of times 
which fuch a ftar’s diftance from us muft exceed that of the fun. 
The quantity of matter contained in fuch a ftar would be 

1§5,2 or 3.738.308 times as much as that contained in the 
fun ; its light, fuppofing the fun’s hght to take up 8’. 7”. in 
coming to the earth, would, with its common velocity, require 
7.900 years to arrive at us, and 395 years more on account of 
the diminution of that velocity ; and fuppofing fuch a far to 
be equally luminous with the fun, it would {till be very fuf- 
ficiently vifible, I apprehend, to the naked eye, notwithftand- 
ing its immenfe diftance. 
22. In the elements which I have empioyed in the above com- 
putations, I have fuppofed the diameter of the central ftar to 
have been obferved, in order to afcertain its denfity, which 
cannot be known without it; but the diameter of fuch a ftaris 
5 much 
