Currents; the former is polarized and responds to reversals of current, while the latter is non-polarized and responds only to the increased current from K2 irrespective of the direction of that current.
In Squier and Crehore's " Synchronograph " system " sine waves of current, instead of sharp " makes and breaks," or sharp reversals, are employed for transmitting signals, the waves being produced by an alternating-current dynamo, and regulated by means of a perforated paper ribbon, as in the Wheatstone automatic system.
Demagnetization by Reversals.-In the course of an experiment it is often desired to eliminate the effects of previous magnetization, and, as far as possible, wipe out the magnetic history of a specimen.
The standard induction in reference to determinations of hysteresis is generally taken as 2500, while the loss is expressed in watts per lb at a frequency of ioo double reversals, or cycles, per second.
Soc., 1886, 40, 495 or by reversals - the source of error due to the transverse cut thus being avoided.