system. (Adapted from Gustave Eiffel, _La Tour de Trois Cents Metres_,
Paris, 1900, p. 127.)]

Everything about the system was on a scale far heavier than found in the
normal elevator of the type. The cylinder, of 38-inch bore, was 36 feet
long. Rather than a simple nest of pulleys, the piston rods pulled a large
guided carriage or "chariot" bearing six movable sheaves (fig. 28).
Corresponding were five stationary sheaves, the whole reeved to form an
immense 12-purchase tackle. The car, attached to the free ends of the
cables, was hauled up as the piston drew the two sheave assemblies apart.

In examining the system, it is difficult to determine what single element
in its design might have caused such a problem as to have been beyond the
engineering ability of a French firm, and to have caused such concern to a
large, well-established American organization of Otis' wide elevator and
inclined railway experience. Indeed, when the French system--which served
the first platform from the east and west legs--is examined, it appears
curious that a national technology capable of producing a machine at such
a level of complexity should have been unable to deal easily with the
entire matter. This can be plausibly explained only on the basis of
Europe's previously mentioned lack of experience with rope-geared and
other cable-hung elevator systems. The difficulty attending Otis' work,
usually true in the case of all innovations, lay unquestionably in the
multitudes of details--many of them, of course, invisible when only the
successfully working end product is observed.

More than a matter of detail was the Commission's demand for perfect
safety, which precipitated a situation typical of many confronting Otis
during the entire work. Otis had wished to coordinate the entire design
process through Mr. Hall, with technical matters handled by mail.
Nevertheless, at Eiffel's insistence, and with some inconvenience, in 1888
the company dispatched the project's engineer, Thomas E. Brown, Jr., to
Paris for a direct consultation. Mild conflict over minor details ensued,
but a gross difference of opinion arose ultimately between the American
and French engineers over the safety of the system. The disagreement
threatened to halt the entire project. In common with all elevators in
which the car hangs by cables, the prime consideration here was a means of
arresting the cabin should the cables fail. As originally presented to
Eiffel, the pla