314 Cooper’s Rotate Piston. 
4h tont 
LHe pateit. 
As this principle and one similar to it are applicable to steam 
b 
detailed description of the principle, and explanatory plates 
will be delayed for a succeeding number. 
late 1 represents the engine of size No. 7, worked by SIX- 
teen men in three positions—a is a side view with the suc- 
tion hose upon the carriage, and without the cranks—b 
shows the rear of the engine and the situation of the cranks 
when in the working position; c the front of the engine with 
the cranks reversed, as when the engine is moved from place 
to place. 
Plate 2 represents the engine of size No. 3, worked by 
eight men. This number has but one pair of cranks as will 
be seen by the side view in a. The three positions are rep- 
resented as in 
The result of several experiments is given, to enable the 
reader to make a comparison with the engines of the old 
construction. 
An engine on the rotative principle, of the size marked 
No. 11, worked by sixteen men, with eleven inches lever, dis- 
charged through a four inch pipe, more water than three 
eight inch cylinders, with nine inches stroke and fifteen inch- 
es lever worked by thirty four men—and as much water as 
four six and a half inch cylinders, nine inches stroke, worked 
by thirty six men with twenty four inches lever. This exper- 
iment was made at the corporation yard, in the city of New 
York, in September 1827. 
e same engine with twelve men, eleven inches lever, 
threw more water than two engines (New York and Hydrau- 
lion,) in the city of Boston, worked by thirty six men wit 
twenty four inches lever. This experiment was made in 
State street, Boston, in September, 1827. 
_. No 7, rotative engine, with twenty men exerting an esti- 
mated power of thirty five pounds per man, with seven inch- 
es lever, threw from an inch pipe one hundred and fifty six 
feet horizontal, and one hundred and nine feet in hei ht. 
; he ——— was at the temperature of 42° and sieckeeh 
y calm. 
