Practical radiography : a handbook for physicians, surgeons, and other users of X-rays (1901)
Isenthal, A. W, Ward, H. Snowden (Henry Snowden), 1865-1911 · London : Published for The Photogram, Ltd. by Dawbarn and Ward, Ltd. · leaf 102
e positive or the negative phasesof the alternating current; a tension spring which permitsof adjustment usually keeps the bar away from the electro-magnet. The bar and the upright supporting it carry theplatinum studs, between which the interruptions of theprimary circuit take place, and the… … Fig. 42. magnetic repulsion and by the tension of the adjustingspring, is pressed back against the contact screw, andthe positive phase of the current passes through thecoil, without, however, acting inductively. When, on theother hand, the negative phase is traversing the electro-magnet, there…
Radiography · X-rays
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