264 On the Jtejijlance experienced by 



gave as a medium of the finking /^ inches; fo that ddc = -/^ 

 inches, and q — 5 lib. 



Let the road confitt of fuch foft fand ; let the inclination 

 a = 4 ; the load P = 1200 lib., the weight of the wheels 

 f = 84 lib. p' = iio lib., 7T = 13a lib. \ their diameter in 

 the fame order as before, 31', 42, and 49 inches. Alfo let 

 m = ~, n = Jj, fi = T ' T , x = .*. ;' OS = 2,' feet and OT = 

 12 feet ; fo that z = ^. In the lad place, let Z> s 3 inches, 

 consequently, 



p- — fin. 2 I = 0-05361, and | = 19 47 ' 



--£■ — fin. 2* = 0-03 130, and u = 3 6° 30' 

 90 



— - — fin. 2 & =0-04315, and S = 18' 23' 



-? (wz 4- n) XP eos. a = 23*276 



(P -f-/> + />') fin. a = 97*242 



(1 P + p) cos. a, fin. 0, tang. I = 125-303 



(I P + />') cos - «b f 111 - ft tan g- « = 107-112 



H = 352'933 

 /-tx P cos. a = 17*101 



(P + fP + ff)ka = 94'3 TI 



(P + tt) cos. a, fin. 0, tang. 3 ss 225-450 



336-862 

 If we fuppofe for two horfes M = 800 and G = 1 1 feet, 

 we (hall have ^ = 3 696 feet and £•' rr 3*861 feet in a fecond. 

 However well the two-wheeled carriages may be eon- 

 ftrueted, however fmall the burden, the inclination of the 

 road, and the height of the centre of gravity, the refiftance 

 is only a little lefs than for four-wheeled carriages. To {how 

 how much depends on the proportion of the wheels, and 

 particularly in regard to carriages of this kind, I {hall in the 

 following examples change only the wheels of the two- 

 wheeled carriages. 



Example II. 

 Sefition 31. 

 Let every thing be as before, onlv for the two-wheeled 

 carriages let GO = 16 inches, tt = 85 lib., and (m m ^ j 

 therefore $ — 24 15', and 



/xxP cos. a m 26' 1 86 



(P + £ P + tt) fin. a = 91*032, 



(P + tt) cos. a, fm. |3, tang. $ = 294-808 



412*026 



Therefore 



