REPORT OF MR. ROBERT B. LINES.
443
The wheel c turns on the same axis as a cog-wheel d (B), the cogs of which, twelve in number, fit into those
of a sliding bar/, d turns the large disc e, which is divided into twelve compartments or spaces, on eleven of which are printed the eleven code or clot-signals used on the Alta Italia Railway, with their meaning in plain Roman characters. The twelfth space is left blank.
For every stroke on the bell, therefore, the disc is turned one space to. the right, and the signal exposed at the top agrees with the number of the strokes. The attendant, hearing the sound of the bell, perhaps from a distance, comes to the signal-box, and having satisfied himself as to the signal, pulls a cord which releases the spring a (Plate A), and the disc, impelled by the weight h (B), falls to the position shown in the cut, with the blank space exposed at the top. The apparatus is simple, inexpensive, and little liable to error.
Plate II.
mm
„ It
Messrs. Siemens & Halske, the widely-known electricians and instrument-makers of Berlin, have also, in their admirable collection, a similar apparatus to that of Leopolder, in which the control consists of an ink-writing Morse register. The apparatus is enclosed in a circular iron box surrounding the bell-support, and is so arranged, that on shutting the door of the box, the circuit is closed automatically should the person sending; the signal have forgotten to close it.
The use of the foregoing apparatus presupposes the existence of a code, and this admits of its being employed, not only to signal the movement of trains, but also to give distress signals, which I have classed by themselves as Group VI., and, in a limited way, to answer the purpose of signals classed under Group II., or even, with a more extended code, °f a speaking telegraph. There are two sets of apparatus, however, employed to signal the movement of traius, on which no code can be used.