INGENUITY AND LUXURY 



the cylinder in which it works are the same as the 

 elevator shaft and are set vertically in the ground be- 

 neath the car. Thus the cylinder of such an elevator 

 working in a one-hundred foot elevator shaft reaches 

 to a depth of one hundred feet under ground. The car 

 is raised by water pressure in the cylinder, the water 

 being expelled in the descent. Such elevators do away 

 with sheaves and winding-drums, use cables only for 

 counter-poise weight, and are entirely practical even 

 in very high buildings in metropolitan districts. 



In electrically operated elevators an electric motor 

 takes the place of hydraulic pressure, being attached 

 to suitable winding machinery, which operates the 

 hoisting cables or plungers. Their advantage lies in 

 the small space occupied by the power plant, and their 

 speed and flexibility in operating place them in 

 a class by themselves. Thus the "push button" con- 

 trol elevators, which are popular in private residences, 

 are so simple in operation that literally the only me- 

 chanical skill required for operating is the ability to 

 push a button. If a person wishes to ascend to the 

 fifth floor, for example, he simply steps into the car, 

 pushes the button marked "five" and the car ascends 

 and stops at the proper landing. Should a person on 

 any floor wish to call the car he simply pushes the call 

 button and waits until the car arrives, which it does 

 automatically, if not in use, stopping at the landing 

 indicated. The door at this landing is also unlocked 

 automatically, so that the passenger may step in and 

 reach any other landing simply by pushing the button 

 indicated. 



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