Conftruoilon of iht Heavens, 2 1 y 
immediately around them ; by which means they will be, in 
time, as it were, condenfed about a center ; or, in other words* 
form themfelves into a cluftet of ftars of almoft a globular 
figure, more or lefs regularly fo, according to the fize and 
original difiance of the furrounding ftars. The perturbations 
of thefe mutual attract ions mufi undoubtedly be very intricate, 
as we may eafily comprehend by confidering what Sir Isaac 
Newton fays in the firft book of his Principia, in the 38th 
and following problems ; but in order to apply this great 
author’s reafoning of bodies moving in ellipfes to fuch as are 
here, for a while, fiuppofied to have no other motion than what 
their mutual gravity has imparted to them, we mufi fiuppofie 
the conjugate axes of thefe ellipfes indefinitely dimmifhed, 
whereby the ellipfes will become firaight lines. 
Form II. The next cafe, which will alfo happen almoft as 
frequently as the former, is where a few ftars, though not 
fuperior in fize to the reft, may chance to he rather nearer each- 
other than the furrounding ones ; for here alfo will be formed a 
prevailing attradlion in the combined center of gravity of them 
ail, which will occafion the neighbouring ftars to draw toge- 
ther ; not indeed fo as to form a regular or globular figure, hut 
however in fuch a manner as to be condenfed towards the 
common center of gravity of the whole irregular ciufter. And' 
this conftru&ion admits of the utmoft variety of fhapes, ac- 
cording to the number and fituation of the ftars which firft 
gave rife to the condenfatiori of the reft. 
Form HI. From the compofition and repeated conjunction 
of both the foregoing forms, a third may he derived, when many 
large ftars, or combined fmall ones, are fituatcd in long ex- 
tended, regular, or crooked rows, hooks, or branches ; for they 
will alfo draw the furrounding ones, fo as to produce figures- 
of 
