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Scientific American Supplement, No. 520, December 19, 1885 by Various
page 48 of 123 (39%)

Safety hooks are often fitted to winding ropes, and although the damage
to life and property is greatly reduced by the use of them, they do not
protect a descending cage from injury in a case of overwinding; besides
which, they are almost useless when a wild run takes place, an accident
which, strange to say, has already occurred many times after engines and
boilers have been laid off for repairs. Stop valves are left open, the
reversing lever is not fixed in mid-gear, steam is got up in the boilers
at a time when no one is in the engine house, and the engines run away.

[Illustration: LEWIS & MASSEY'S AUTOMATIC SAFETY GEAR.]

Various devices have been suggested and tried as a preventive, but their
application has either caused as much mischief as a bad accident, or it
has depended upon the driver doing something intentionally; whereas in
the automatic gear of Messrs. Massey and Lewis, of which an illustration
is annexed, there is nothing to cause damage or to interfere in any way
with the proper handling of the engines, and it is practically out of the
power of the driver to render the gear inoperative. It is here shown in
its simplest form as applied to the ordinary reversing and steam handles
of a winding engine, the only additions being an arm jointed to the top
of the valve spindle, with its connections to the shaft of the reversing
lever, and a disk receiving a suitable motion from the main shaft of the
engine. On the disk is a projecting piece or stop which is brought into
such positions, at or near the end of each journey, that the stop valve
cannot be opened, except slightly, when the reversing lever is not set
for winding in the proper direction, or when the cages have reached a
point beyond which it is undesirable that the engine driver should have
the power of turning on full steam. Thus, if one cage is at bank, the
driver cannot draw it up into the head gear suddenly; but after it has
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