MECHANICAL AND ELECTRICAL OSCILLATORS.

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direction before. No doubt many inventors, at one time orother, have entertained the idea of generating currents by at-taching a coil or a magnetic core to the piston of a steam engine,or generating currents by the vibrations of a tuning fork, orsimilar devices, but the disadvantages of such arrangements froman engineering standpoint must be obvious. Mr. Tesla, however,in the introductory remarks of his lecture, pointed out how by aseries of conclusions he was driven to take up this new line ofwork by the necessity of producing currents of constant periodand as a result of his endeavors to maintain electrical oscillationin the most simple and economical manner.