. Electrical world. n-limited range without any alteration to the aerial wires or otherconducting masses used to pick up the waves. Prof. Fessenden some time ago pointed out the impossibility ofobtaining a direct mechanical movement from the oscillations, owingto their extremely high frequency. By using an extraneous source(a rotating field) to supply the energy, and making use of the novelproperty which I discovered—that by passing such oscillations alonga magnetic wire, itself subjected to a rotating magnetic field, thdhysteresis is enormously increased, the effect of the oscillations beingt
. Electrical world. n-limited range without any alteration to the aerial wires or otherconducting masses used to pick up the waves. Prof. Fessenden some time ago pointed out the impossibility ofobtaining a direct mechanical movement from the oscillations, owingto their extremely high frequency. By using an extraneous source(a rotating field) to supply the energy, and making use of the novelproperty which I discovered—that by passing such oscillations alonga magnetic wire, itself subjected to a rotating magnetic field, thdhysteresis is enormously increased, the effect of the oscillations beingto permit more of this externally supplied energy to be utilized—thisdifficulty is overcome, the same effect being obtained, and to a vastlyincreased extent, as if the direct electro-dynamic effects of the oscil-lations were made use of. The instrument depends, as before stated,upon the increase of hysteresis (in the sense of work done per re-versal) produced in a bobbin of steel wire, placed in a rotating FIG. 2.—DETECTOR WITH COVERS REMOVED. when oscillations are passed through the wire itself, such oscillationsproducing an oscillatory circular magnetism superimposed on thevarying longitudinal magnetization. The principle and the prelim-inary experiments leading up to the design of the present instrumentare described in a paper by Dr. Ewing and myself on A New Methodof Detecting Electrical Oscillations, read before the Royal England, on February 11, 1904. Briefly, the instrument is an adaptation of the Ewing hysteresistester, in this case the specimen being held fast and the magneticfield revolving, being driven by an electric motor. The bobbin, whichis supported on pivots in jewels, is prevented from following thefield by means of a controlling spring. The winding on the bobbinis made as nearly non-inductive as possible by being double-wound,and consists of a number of turns of very fine insulated steel wire,the plane of the turns being at right
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectelectri, bookyear1883
