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INVENTIONS OF NIKOLA TESLA.

ful dynamic inductive effect on the coils c o' is produced. Be-sides the currents generated in the secondary coils by dynamo-magnetic induction, other currents will be set up in the samecoils in consequence of many variations in the intensity of thepoles in the ring a. This should be avoided by maintaining theintensity of the poles constant, to accomplish which care shouldbe taken in designing and proportioning the generator and indistributing the coils in the ring a, and balancing their effect.When this is done, the currents are produced by dynamo-mag-netic induction only, the same result being obtained as thoughthe poles were shifted by a commutator with an infinite numberof segments.

The modifications which are applicable to other forms of con-verter are in many respects applicable to this, such as those per-taining more particularly to the form of the core, the relativelengths and resistances of the primary and secondary coils, andthe arrangements for running or operating the same.