REPORT OF MR. ROBERT B. LINES.
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on the semaphores A and A 1 . Turning it to b would reverse the arrangement. It is obvious that the battery can only be on one pair of signals at a time, and that a white signal on one road necessarily involves a red one on the other. By placing S between the studs a and b , all the signals may be kept at red, except when a train on either road is to be passed over.
5. Signals Between the Various Portions of a Train.
The signals embraced under this head are so few and com- paratively so unimportant, that, but for the distinctiveness of their object, they would scarcely be entitled to separate classification. In Europe, where the cars are divided into compartments and the passengers locked therein, a necessity may sometimes arise for immediate communication between the passenger and the guard or conductor ; but even in such cases the ordinary American bell-rope -would seem to be as certain and convenient as the electrical and pneumatic apparatus in use on some European roads. I have seen at the Exposition an elaborate piece of mechanism, worked by compressed air, by means of which a passenger in danger was enabled to ring a bell in the conductor’s car, and to light a lamp at the door of his own compartment at the same time, so that the conductor might know exactly where his assistance was .needed. It does not seem probable, however, that such an apparatus could ever be required on American railroads. To warn the conductor or engineer of the breaking of a train the bell-rope would also seem sufficient; or, if not, an arrangement similar to that used by Mr. Pope in his block-signalling system would obviate all danger.
Electric brakes have from time to time been invented, but, so far as I know, never applied with anything like the success which has attended the operation of the air-brake system. One of these, the invention of M. Achard, is on exhibition at Vienna. Frequent experiments have been made with it on various French railways, but none have been altogether successful. Neither the brakes, however, nor the various contrivances for electrical gas-lighting, etc., on trains, properly come within the scope of this report.
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