ation of structural
ironwork, running it up high."

Into this converted structure was put the most complete steam plant
obtainable, together with all the mechanical and engineering adjuncts
bearing upon economical and successful operation. Being in a narrow
street and a congested district, the plant needed special facilities for
the handling of coal and ashes, as well as for ventilation and forced
draught. All of these details received Mr. Edison's personal care and
consideration on the spot, in addition to the multitude of other affairs
demanding his thought. Although not a steam or mechanical engineer, his
quick grasp of principles and omnivorous reading had soon supplied the
lack of training; nor had he forgotten the practical experience picked
up as a boy on the locomotives of the Grand Trunk road. It is to
be noticed as a feature of the plant, in common with many of later
construction, that it was placed well away from the water's edge,
and equipped with non-condensing engines; whereas the modern plant
invariably seeks the bank of a river or lake for the purpose of a
generous supply of water for its condensing engines or steam-turbines.
These are among the refinements of practice coincidental with the
advance of the art.

At the award of the John Fritz gold medal in April, 1909, to Charles T.
Porter for his work in advancing the knowledge of steam-engineering, and
for improvements in engine construction, Mr. Frank J. Sprague spoke on
behalf of the American Institute of Electrical Engineers of the debt of
electricity to the high-speed steam-engine. He recalled the fact that
at the French Exposition of 1867 Mr. Porter installed two Porter-Allen
engines to drive electric alternating-current generators for supplying
current to primitive lighthouse apparatus. While the engines were not
directly coupled to the dynamos, it was a curious fact that the piston
speeds and number of revolutions were what is common to-day in isolated
direct-coupled plants. In the dozen years following Mr. Porter built
many engines with certain common characteristics--i.e., high piston
speed and revolutions, solid engine bed, and babbitt-metal bearings; but
there was no electric driving until 1880, when Mr. Porter installed a
high-speed engine for Edison at his laboratory in Menlo Park. Shortly
after this he was invited to construct for the Edison Pearl Street
station the first of a series of engines for so-called "steam-dynamos,"
each indepen