C^70 . , 
( who^s proportion to this is givoi ) iii the fame uniform 
Medium. 
33. And this being known as to one Medium ; the fame 
is thence known as to any other Medium^ the proportion 
of who's refiftance to that of this is known. 
34. If a he^vy body be projc£led downward in a pendi- 
i. ± ^ 
cular line ; it delcends therefore at the rate mm^ m\ &€. 
of ( the imprefTed force ) increafed by m^m-^m^y m -f- 
-f" of^ t'^? impulfe of Gravity ; ( by ^ 7. & 
^ 27. ) Becaufe both forces are here united. 
35. If in a perpendicular projedion upwards; it at 
cends in the rate of the former, abated by that of the lac- 
ter. Becaufe here the impulfe of Gravity is contrary to 
the force imprefTed. 
36. When therefore this latter ( continually increafing ) 
becomes equal to that former ( continually decreafmg ) 
it then cealeth to afcend • and doth thenceforth defcend 
at the rate wherein the latter continually exceeds tlie for- 
mer. 
37. In an Horizil^iital or Oblique projeftion : If to a 
Tangent who's increments are as i^ L, LM, MNy &c; 
that is as &c. be fitted Ordinates ( at a given an- 
gle) who's increments are as FL, FA/, FA^, &c. that is 
as-^^, &c: The Curve anfwerirjg to the compound of 
thefc Motions, is that wherein the ProjeCt is is to move. 
58. 1 his Curve ( being hitherto without a name ) 
may be called tinea Proje^omrv ; tiie line of Frojefts, or 
things projefted; which refembles a Parabola deform- 
ed. 
i;. The Celerity and Tendency, as to each point of thi 
line, is determined by a Tangent at that Point. 
4c. Ajiid that agaiafl which it makes the greatefl flrok 
