Mifcellanea Curiofa. 345 



terminated at the Hyperbola : The Aggregate 

 of which is h FN&n. From whence if we fub* 

 duct the Aggregate of Ablatives FT; the re- 

 maining Trilinear h&n> reprefents the Defcenr. 



50. If to this of Gravity, be joined a project- 

 ing Force ; which is to the Impulfe of Gravity as 

 as to h F (be it greater, lefs, or equal) ta- 

 ken in the fame Line ; the fame Parallels deter- 

 mine proportional Parallelograms, whole Aggre- 

 gate is KiQ. & 



And therefore if this be a perpendicular 

 Projection downwards; then h^n (the Sum of 

 this with the former; reprefents the Defcent. 



£1. If it be a Perpendicular upwards; thea 

 the difference of thefe two reprefents the Motion ; 

 which fo long as 2^ is the greater, is Afcen-, 

 dent; but Defcendent, when hbn becomes 

 greater ; and it is then at the higheft when they 

 be equal. 



jTg. If the Projection be not in the fame Per- 

 pendicular, (but Horizontal, or Oblique) then 

 *C ft. reprefents the Tangent of the Curve ; and 

 h ft» the Ordinates to that Tangent, at the gi- 

 •ven Angle. 



, 54. But the Computation before given, I take 

 to be of better ufe than this Reprefentation in 

 Figure. Becaufe in fuch Mathematical Enqui- 

 ries, I choofe to feparate (as much as may be) 

 what purely concerns Proportions; and confider 

 it ^bftradUy from Lines, or other Matter where- 

 with it is incumbred. 



As to the Queftion propofed ; whether the re- 

 fiftance of the Medium do not always take off 

 fuch a proportional part of the Force moving 

 through it, as is the fpecifick Gravity of the Me* 

 Hum to that of the Bodjf moved in it : (For, if 



