THE CUTTRISS VIBRATOR.

For vibrating the siphon of the Siphon Recorder. The siphon must be kept in constant vibration to do away with friction between its point and the paper ribbon, otherwise no reliable record of the movements of the Recorder coil can be obtained, the current from the cable being too feeble to overcome even a very small amount of friction. Sir William Thomson, the inventor of the Siphon Recorder, employed static electricity, which maintained vibration admirably in a dry atmosphere, but in the presence of moisture was wholly unreliable. The Cuttriss Vibrator is a magnetic arrangement entirely independent of climatic conditions. It maintains ample vibration and requires no special attention.

THE AUTOMATIC SENDER.

Two forms of Automatic Senders are in the exhibit. Automatic transmission has been in successful operation on land lines for many years, but was not considered valuable or even practicable on long submarine cables until Mr. T. J. Wilmot, The Commercial Cable Company's Superintendent at Waterville, Ireland, produced a modified form of Wheatstone Automatic Transmitter, and demonstrated conclusively that it was swifter and more accurate than keys manipulated by the hand. The signals received from an Automatic Sender are uniform in shape and size, whereas those from the hand vary with the operator. The Automatic Sender, therefore, not only does more work in a given time, but what is much more important, the uniformity of its signals enables the receiving operator to translate them with greater certainty. The liability of errors is con-sequently minimized. Motion is imparted to the transmitter by means of a weight, and the electrical contacts are controlled by a paper ribbon perforated with three rows of holes. The upper and lower rows determine the

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