the three types of compressors at St. Fargeau--Fig. 10 being a diagram
of the Riedler compressor--and indicate the gain derived from the
intermediate cooling. The loss is shown to be only 12 per cent., as
compared with a loss of 43 per cent. in a large part of the plant, and
of 105 per cent. in the earlier compressors of the St. Gothard type.
The table given herewith contains a summary of trials made by
Professor Gutermuth, and are intended to show the comparative results
of an extended trial with three kinds of compressors at St. Fargeau.

PERFORMANCES OF COMPRESSORS AT THE ST. FARGEAU CENTRAL STATION.

--------------+-------+--------+------+-------+--------+--------+---------+
| R p | | E | | | | |
| e o e | Horse- | f |Amount |Quantity| Cubic | |
Compressors. | v f r | Power | f |of Air | of Air |Feet of |Final Air|
| o |Absorbed| i |Passing| Passing|Air per |Pressure.|
| l E m | by | c |through| through| Horse- | |
| u n i |Compres-| i | Inlet | Valves | Power | |
| t g n | sors. | e | Valves| per | and per| |
| i i u | | n | each | Hour. | Hour. | |
| o n t | | c |Revolu-| | | |
| n e e | | y | tion. | | | |
| s . | | . | | | | |
--------------+-------+--------+------+-------+--------+--------+---------+
| | | | cubic | cubic | |lb. per |
1. | | | | feet | feet | |sq. in. |
_Sturgeon_ | | | | | | | |
_Compressor_ | 37 | 302 | .87 | 41.67 | 91,507| 261.3 | 90 |
Diameter of | 37 | 258 | .87 | 38.13 | 84,650| 276.1 | 90 |
cylinder, | | | | | | | |