340 Mifcellanea Curiofa. 



z6. If we take' in the Confideration of rhe 

 Air's Refi fiance ^ we are then, for each of thefe 

 equal Progreilions, to fubftitutea decreafmg Prc- 

 greflion Geometrical ; in like manner ( and for 

 the fame Reafbns) as in the Line of Projection. 



27. Hence arifetb, for the 



firft Moment — \ for the fe- — 



m 



m m 



cond — h; ~ j for the third — - -— 



mm mm 



1 1 t c j A J III 



*~ f- — h — t) And — — — 



m m m m 3 m m 



fuch is therefore the Defcent i 1 1 

 of a heavy Body falling by its m*~rr$~ni 

 own weight. The feveral Im- 

 pulfes of Gravity being fuppofed equal. 



x8. That is (in the Figure of 5 iz) as FL, 

 FM, FN, &x. in the Line of Defcent, anfwcr- 

 ing to FL 9 L M, M N, 6cc. in the Line of Pro- 

 jection. 



29* But though the Progreflions for the Line 

 of Projection, are like to each of thofe many in 

 the Line of Defcent ; it is not to be thence inferred, 



in 



that therefore — in the one, is equal to — 

 m m 

 the other : But in the Line of Projection (fup- 



pofe) — /(fuch a Part of the Force impreffed, 

 and a Celerity anfwerable : ) in the Line of De- 

 fcent, — g fucb a Part of the Impulfe of Gra- 



vity. 



30. Thofe for the Line of Defcent Cof the 

 fame Body) are all equal, each to other : Becaufe 



g ( the 



