CotifiruclioTi of the HeaVtns. 2 1 5 



immediately around them ; by which means they will be, hi 

 time, as it were, condenfed about a center ; or, in other words, 

 form themfelves into a clufter of flars of almoft a globular 

 figure, more or lefs regularly fo, according to the fize and 

 original diftance of the furroundiPig ftars. The perturbations 

 of thefe mutual attraflions mufl: undoubtedly be very intricate, 

 as we may eafily comprehend by conflderlng what Sir Isaac 

 Newton fays in the firfl: book of his Principla, in the 38th 

 and folio .vlng problems; but in order to apply this great 

 author's reafonlng of bodies moving in ellipfes to fuch as are 

 here, for a while, fuppofed to have no other motion than what 

 their mutual gravity has imparted to them, we muil: fuppofe 

 the conjugate axes of thefe ellipfes indefinitely diminilhed, 

 whereby the ellipfes will become flralght lines. 



Form II. The next cafe, which will alfo happen almoft as 

 frequently as the former, is where a few ftars, though not 

 fuperlor in fize to the reft, may chance to be rather nearer each 

 other than the furrounding ones j for here alfo will be formed a 

 prevailing attraction in the combined center of gravity of them 

 all, which will occafion the neighbouring ftars to draw toge- 

 ther ; not indeed fo as to form a regular or globular figure, but 

 however in fuch a manner as to be condenfed towards the 

 common center of gravity of the whole irregular clufter. And 

 this conftruClion admits of the utmoft variety of fhapes, ac- 

 cording to the number and fituation of the ftars which firft 

 g-ave rife to the condenfation of the reft. 



Form III. From the compofition and repeated conjun£tloit 

 of both the foregoing forms, a third may be derived, when many 

 large ftars, or combined fmall ones, are fituated 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 



