[Illustration: DAVEY'S PENDULUM FOR SYNCHRONIZING CLOCKS.
W, friction wheel attached to pendulum. L gives no impulse except when the electro-magnet is excited. K, lever and weight lifted by electro-magnet, E. A, open contact completed by pendulum each swing. B, battery. R, ratchet wheel and pawl. M, lever fixed at top. L, weight at end of bell crank lever, which drives pendulum once each minute, being raised by the electro-magnets.]
At the recent meeting of the Institution of Mechanical Engineers, Dublin, Mr. Davey, of Leeds, spoke of synchronizing mechanisms. He had occupied some of his spare time in attempting to synchronize clocks from a standard clock. The problem is similar to the present one, except that it is rough-and-ready, compared to the present one. He had a novel electrical pendulum, to drive a seconds pendulum by electricity. Electrical clocks are notoriously bad timekeepers; on account of variation in the strength of the electrical current, the battery falls off. He had constructed an electric clock having a seconds pendulum, and recording an impulse once a minute. On the pendulum he had a little ratchet wheel, R, having thirty teeth. The pawl was connected with a lever, M, fixed at the top. On the face of the wheel a little pin rotates with the wheel. On the side of the clock case was a contact maker, which closed the circuit by the pin on the ratchet wheel, R, once every minute. The weight was lifted by the electric current, and by its fall gave an impulse to the pendulum. The pendulum was a free swinging pendulum for 59 sec., and the increase of the arc could scarcely be detected.
About three years ago, when the sudden and serious fall took place in the value of the secondary products produced in gas works, many gas managers--ever desirous of doing their very best for their employers--were forced to look around for some better market in which to dispose of the products which had so seriously fallen in value. This was no easy task; and even now it forms very uphill work indeed. A comparatively new market has been created for the disposal of boiled tar at several of the German ports. But the expense and difficulty of loading ships with tar in casks take very much from the saving derived from the new manner of disposal. It occurred to me, therefore, that we must look nearer home for a remedy.