Write us for Circulars and Prices.
Main Office and Works, 1105 Frankford Avenue,
PHILADELPHIA.
New York Office, 108 Liberty Street.
New Haven " 82 Church Street.
Pittsburg " 413 Fourth Avenue.
Boston Office 19 Pearl Street.
Baltimore " Builders' Exchange.
Scranton " 425 Spruce Street.
Figure 19.--The electric elevator in its earliest commercial form (1891),
with the motor connected directly to the load. By this time, incandescent
lighting circuits in large cities were sufficiently extensive to make such
installations practical. However, capacity and lift were severely limited
by weaknesses of the control system and the necessity of using a drum.
(From _Electrical World_, Jan. 2, 1897, vol. 20, p. xcvii.)]
[Illustration:
MILLER'S PATENT
LIFE AND LABOR-SAVING
SCREW HOISTING MACHINE,
FOR THE USE OF
Stores, Hotels, Warehouses, Factories, Sugar Refineries,
Packing Houses, Mills, Docks, Mines, &c.
MANUFACTURED BY
CAMPBELL, WHITTIER & CO., ROXBURY, MASS.
_Sole Agents for the New England States._
The above Engraving illustrates a very superior Hoisting Machine, designed
for _Store and Warehouse Hoisting_. It is very simple in its construction,
compact, durable, and not liable to get out of order. An examination of
the Engraving will convince any one who has any knowledge of Machinery,
that the screw is the only safe principle on which to construct a Hoisting
Machine or Elevator.
Figure 20.--Advertisement for the Miller screw-hoisting machine, about
1867 (see p. 23). From flyer in the United States National Museum.]
[Illustration: Figure 21.--The first widespread use of electricity in the
elevator field was to drive belt-type mechanical machines and the pumps of
hydraulic systems (see p. 14) as shown here. (From _Electrical World_,
Jan. 4, 1890, vol. 15, p. 4.)]