rai ram as erg” 
ck ek idea ob 
Ward's Steam-Engine. $1 
vented a Revolving Engine, which, it was supposed, had 
BS ‘completely triumphed over the difficulty of reciprocation. 
It may seem hardy to question a dogma, which has re- 
mained so long unquestioned ; but [ hold it equally pusil- 
lanimous never to think ourselves at liberty to examine re- 
ceived doctrines; and I hope you and your readers will, 
therefore, excuse my presumption, in endeavouring to ney 
contrary to the received ss that there is no los 
power in the reciprocating movement of the common nal 
engine, and that the well ice principles of mechanics 
7 . applied to the subject, under a cystineng er of 
the fact 
It is necessary, in the first place, to reduce to some — 
ra 
of motion toa State of rest.” How a 
i where does this 
* dragging” take place? The senaaeee het used, can only 
mean, that the power of the steam, being exerted upon the 
reciprocating mass, in a direction opposite to that, in which 
it is moving, Overcomes its momentum, and causes it to 
stop. At what point, then, in the revolution of the crank, 
is the power of the steam thus exerted, and this cessation 
of movement affected? pposing the crank to start from 
the upper dead-point, n seek operation can take place at 
any point in the first | of the revolution ; for nobody ev- 
er disputed, that during this half, the power of the steam 
continues to be exerted, and the reciprocating mass to move, 
in the same directions, which they Sea wietre — at the 
commencement. That such a cessation of mov t can- 
not be effected in the other half of the wicket: that} is, 
pr ee the crank has passed the lower dead-point, is “bg 
from the same considerations. Aad if, t it 
akes place at any point, in the whole revolution, it must 
be ey a 
“ing see ae reciproca iting es: ina divective op- 
n 
prop osition sedabtiys assumes two facts: Ist. that, at the 
d-point, the power of the steam is in full operation ; 
_ and Badly, that, at the isitane the reciprocating mass 
