efficiency--a consumption of 611, 752, and 720 cubic feet per brake
horse power. It is very evident from the foregoing that the Compressed
Air Company, of Paris, will never do itself justice until as much
thought and care has been devoted to the economical use of the motive
power as has been expended in the means of producing it, and Professor
Riedler's recent investigations should be especially useful in this
respect. The question has indeed attracted the attention of more than
one manufacturer, and reference is made to a particular type of small
rotary motors which are being constructed by MM. Riedinger & Co., and
which is stated have given very excellent results. These engines were
specially used for working sewing machines and developed on the brake
an efficiency of 34.07 and 51.63 foot pounds per second. Trials were
made with a half horse power variable expansion Riedinger engine.


TRIALS OF A SMALL ROTARY RIEDINGER ENGINE.
______________________________________________________________
| |
Number of trials. | I. | II.
______________________________________________|_______|_______
| |
Initial air pressure. lb. per square inch | 86 | 71.8
" temperature. deg. Cent. | +12 | +170
Ft. pounds per second measured on the brake. | 51.63 | 34.07
Revolutions per minute. | 384 | 300
Consumption of air for one horse power per | |
hour. | 1,377 | 988
______________________________________________|_______|_______