L244]

POE O he Manner of placing the Carriage OIL

ibe W heels.

Let abcd(fig. 10.) repreſent the body of a carriage, and ſuppoſe it pla- ced on à pair of wheels, which require no packing, the half height of the wheel being n p. Suppoſe it again placed on a pair of wheels, whoſe half height is O Pp, 0 as to reguire a packing to raiſe it to the ſame height with the other, The height of the packing will then be equal to n o. In a level road this will make no difference of weight on the horſe's back, Butif the carriage ſhould be going down a road, making an angle with the horizon of about 1 5 degrees, it

will make a conſiderable difference, as

may