STANDARD CELL.

Invented and manufactured by Dr. Alex. Muirhead, of London, for the Commercial Cable Company. Its use is to measure the strength of other cells, batteries, or electric currents from any source, its own force being known and invariable.

THE CUTTRISS MOTOR.

For drawing the paper ribbon under the point of the siphon, designed specially for the purpose. A sensitive governor regulates its speed and consequently that of the ribbon. The speed of the ribbon must be absolutely regular to preserve uniformity in the record made by the siphon, otherwise the record could not be translated with any certainty. The ribbon moves under the siphon at the rate of 40 inches per minute. The governor when once set will maintain any given rate within the half of one per cent. The motors are so wound as to run equally well on an electric light circuit, or a battery circuit with six or more gravity cells.

This Company's system is equipped with the Muirhead duplex.

Its cables were manufactured and laid by Messrs. Siemens Bros. & Co., Limited, of London, England.

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