AMERICAN INSTITUTE. l4l 



a shaft, so tliat when the balls (UU) are thrown out bj centrifugal 

 force, the spurs (aa) force down the cap (c), which rests on a 

 helical spring (c') in a cup in the upper end of an inverted cone 

 (B), attached to and rotating with the shaft (F). The conical 

 surface of the inverted cone (B) is fitted to a conical cavity in the 

 upper end of the column (A). 



The sliding rack (M) is to be connected in any suitable manner 

 with a throttle valve, or with the aj)paratus which closes the cut- 

 off valves of a steam engine, if the governor is applied to a steam 

 engine, or with the gate which lets in the water on to a water 

 wheel, if applied to govern the speed of water wheels. 



From the foregoing it will be seen, that whenever the speed of 

 the engine is too great, the balls (UU) will be thrown out by cen- 

 trifugal force 5 this will gradually compress the helical spring, 

 and by degrees increase the friction of the cone (B) with the coni- 

 cal cavity of the column; and as the cone (B) is feathered to and 

 turns with the shaft (F), this gradually increasing friction will 

 gradually retard the motion of the shaft (F), and as this is gra- 

 dually retarded, the hub (S) is gradually started by the deferen- 

 tial wheel (I), which by the cogged sector (S') moves the sliding 

 rack (M), lifting its weight or spring, which operates the valve to 

 admit less steam, if a throttle, or to cut off shorter if a cut-off, or 

 to admit less water if a water wheel. And as the increased fric- 

 tion of the cone reduces the velocity of the shaft (F), the balls 

 will be depressed by gravity, and the helical spring (D), to relieve 

 the friction after the regulating motion has been induced. 



It will be seen also, that the instant the speed of the motive 

 power or pulley (L) is altered, a corresponding change of power 

 is required to affect the shaft (F). Now, at a regular speed, the 

 power required to drive the shaft (F) and move the governing rod 

 being exactly balanced by the weight or spring (P), when the 

 speed is altered, the rack (M) will move before the shaft (F) has 

 begun to change its speed; and, if the increase or decrease of the 

 speed of the motive power be very sudden, the rack can move to 

 its full extent by one-half a revolution of the pulley. 



When the governor is used on marine or portable engines, 

 instead of the pendulum balls, a balanced bar, with a ball at each 



