Filament.—That part of an incandescent lamp which gives out the light.
Field-Magnets.—In a dynamo the magnets between which the armature revolves.
Foot Pound.—The British Unit of work, or 1 lb. raised 1 foot high.
Galvanometer.—An instrument for measuring current.
Generator.—Another term for a dynamo.
Governor.—An apparatus for controlling the speed of any motor.
Horse-Power (HP.)—indicated HP.—The Unit is 33,000 lbs. lifted 1 foot high per minute. The nominal HP. of any motor is generally fixed considerably less than the indicated.
| Ind. HP. of any engine = | 2(A P R S) |
| 33,000 |
| A = | Area of piston in square inches. |
| P = | Average pressure of steam in lbs. per square inch. |
| R = | Number of revolutions per minute. |
| S = | Length of stroke in feet (if in inches, × 33,000 by 12). |
The French “force cheval” represents 32,560 foot pounds.