216 
Steam Engine^ 
It appears necessary to give the reader some idea of the 
principles of the steam engine which is to produce such 
novel and strange effects ; and this I will endeavour to do 
in as few words as I can, by shewing the extent to which 
the principles are applied already. 
To make a steam as irresistible, or powerful as gun= 
powder, we have only to confine and increase the heat by 
fuel to the boiler. A steam engine with a working cy=^ 
Under only nine inches in diameter, and a stroke of the 
piston three feet, will exert a power sufficient to lift from 
3,000 to 10,000 pounds perpendicularly, two and a half 
miles per hour. This power applied to propel a carriage 
on level roads or rail-ways, would drive a very great 
weight with much velocity, before the friction of the axle- 
free or resistance of the atmosphere would balance it. 
This is not speculative theory. The principles are now 
in practice, driving a saw-mill at Manchacks on the Missis- 
sippi ; two at Natchez^ one of which is capable of saw- 
ing 5000 feet of boards in 12 hours ; a mill at Pittsburgh^ 
able to grind 20 bushels of grain per hour ; one at Ma- 
rietta of equal powers ; one at Lexington, (Ky.) of the 
same powers ; one a paper-mill, of the same ; one of one 
fourth the power at Pittsburgh : one at the same place of 
3| times the power, for the forge, and for rolling and split- 
ting sheet iron ; one of the power of 24 horses at Middle- 
town, (Con.) driving the machinery of a cloth manufac- 
tory ; two at Philadelphia of the power of five or six hor- 
ses, and many making fCr different purposes ; the princi- 
ples applying to all purposes where power is wanted. 
OLIVER EVANS. 
Ellicotfs Mills on the Patapsco, 
Nov, 13, 1812. 
A new fire engine, —'M.dk.Q a small engine of tin and 
leather^ to contain one cubit foot, or 6 gallons of water, 
\yhich tveiglts 62| lbs. with a piston to project the water 
