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and self-closing, folding car gates as were previously described. The capacity of this elevator is 1,500 pounds at 300 
feet per minute, and the winding machine is of the worm-gear 
traction type, placed over the well.
       One elevator with a capacity of 2,500 pounds at 50 feet 
per minute is provided to carry freight between the first floor 
and the basement; it is operated by full automatic push button 
control.
       All these elevators have the locks on the well doors and 
the switches on the well doors and car gates so connected that 
the cars cannot be moved unless the car gates are closed and 
the well doors closed and locked.
       Two dumb-waiters are provided to carry small loads 
between the floors of the stack; they have a capacity of 200 
pounds at 200 feet per minute and run from the basement to 
the seventh mezzanine floor, serving sixteen landings. The
movements of the cars are controlled by groups of push 
buttons at each landing for each dumb-waiter, by means of 
which the cars can be called to any floor from any point in 
the well or sent from any floor to any other floor. The control 
for the dumb-waiter is such that a car moving downward 
may be stopped at a landing between its position at the time 
when the call button is pushed and its destination, but no 
other buttons will affect the movement of the car until it has 
reached the point to which it was sent. Door locks and 
switches are provided so that the cars cannot move unless 
the well doors are closed and locked. On the arrival of either 
or both cars at any landing, one of the sets of signal lamps 
previously described is lighted and remains so until the well 
doors are opened. The well doors are of the vertically sliding 
type and are not self-closing.

BOOK CONVEYOR

       This conveyor was installed to carry books from any of 
the sixteen floors of the stack and deliver them into a receptacle 
in the space directly back of the delivery desk. The