CAB SIGNALS IN GENERAL.                 593

as an auxiliary to the clear color signal, and here another
pair of coils and another neutral armature will be needed.
No other normal danger cab signal can operate all of these
functions for all possible sequences of track condition with
as few as five pairs of electromagnets and five neutral
armatures.
  In the case of a ramp whose top surface lies entirely in
one plane, that is a ramp without sloping ends, the Dam-
mond system reduces ramp impact ON STRIKING FACE
fully seventy-five per cent, although the ramp is a rigid
member. This enormous reduction (amounting, practically,
to entire elimination) is effected absolutely without compli-
cating construction. Detailed and conclusive proof of this
assertion will gladly be supplied on request. As a matter
of fact, the Dammond system employs ramps with sloping
ends, thus effecting a still further reduction of any tendency
to break impingeing members. Repeated tests on the track
and locomotive of the Railway and General Engineering
Co. prove that a ramp length not to exceed thirty feet is
sufficient in the Dammond system for the highest speeds oc-
curring now on any railway. In case the impingeing mem-
ber should become worn to such a degree as to fail to be
raised sufficiently by the ramp the dangerous error would
result in every cab system now in use. In the Dammond
system alone, this wearing would produce the safe error.  If
the impingeing member should break, the dangerous error
may be produced in other cab systems, while only the safe
error could result from such an accident in the Dammond
system.
  Excluding for the moment certain objectionable cab sys-
tems which have been proposed and which, after fair tests,
have been rejected as impractical, it may be said that the
Dammond system is the only normal danger cab system in
which the proper indication is given continuously. For in-
stance, in certain other cab signals a distant indication
would be given only while the locomotive is at the distant




			

OHS/National Afro-American Museum & Cultural Center Serial Collection

African Methodist Episcopal Church Review, Vol. 28, Num. 2

Volume:  28
Issue Number:  02
Date:  10/1911