__[ 200 ] 
for E'T 1 x EW ■=. MA\ Z x AN, ex hypoth. E1V\ AN 
: : MAj z : Etff, and confequently ^EW\y/~AN:i 
MA : £7*. The friction too is diminilhed with the 
flownefs of the motion, and becaufe the periphery 
increafes in a lefs ratio than does the area of a circle. 
The refult of the whole then is in favour of the 
broad cylinder ; and ftill the broader the better ; for 
iinlefs fome mechanical confederations fhould limit 
the problem, ’tis evident in a geometrical fenfe, that 
there is no limitation. A disadvantage might arife 
perhaps to the effeCt of the jet d’eau from thus in- 
creafing the breadth ; which however would be re- 
medied, I think, by a number of thefe jets : but be 
that as it will, ’tis certain, that to augment the dia- 
meters, and diminifh the lengths of the Smaller kind 
of cylinders, now ufed, could have no fuch incon- 
venience, nor fail of being attended with an augmenta- 
tion of force. 
What I think might be further obferved for the 
improvement of this engine is in the boiler and 
fleam, but more connected with experiments; which 
fliould I have an opportunity to moke, I may re fume 
perhaps the fubjeCt, if they anfw.er my expectation. 
XXX. 
