642 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1911. 
graphical form the quickening in speed from the opening of the 
line in 1880 to the present time. You will notice that this increase 
of speed has been followed by remarkable results; the first immedi- 
ate result is the possibility of a greater number of trains, and the 
curve of the rise in the number of trains is shown on the diagram; 
but the really significant feature is the rise in the number of passen- 
gers carried, 35,000,000—72,000,000, which is the direct result of the 
increased facility in traveling. Now, it is in such a case that the 
importance of the sig- 
naling and braking come 
to be almost preemi- 
METROPOLITAN - DISTRICT RAILWAY nent, quite apart from 
Goiswion loosed ERUNG) the mere mechanical 
problem. 
IT may point out that 
the District Railway, 
in common with most 
other electric railways 
of this country, has 
what is known as a 
“track system of signal- 
ing,’ which apart from 
the fact that the driver 
holds what is known as 
‘“‘the dead man’s han- 
dle,”’ which upon being 
released causes the train 
to stop, the train inde- 
pendently stops itself 
upon coming to a por- 
tion of the line not 
1880 1890 a ee cleared by the previous 
ee train. 
eee | IT have given you 
some examples that this country is not’ so far behind as we are so 
often told; and we have another in the fact that the District Rail- 
way has created a most beautiful system, by which the signalman 
is now absolutely independent of fog or darkness; he can see every 
train, or rather its picture, as it moves along the track in an illumi- 
nated diagram in front of him. No one could watch, as I have had 
the privilege of doing, the operation of this system in a signal box 
without feeling certain that it must become universal in a very short 
time. You may like to see an actual panel from a signal box anda 
view of what the interior is like with the signalman operating, 
instead of cumbrous levers, only a few small handles. 
72,732,612 
