The current required for it is generated by dynamos driven from the axles of the coaches.
Stimulated and assisted by improvements in the construction of large dynamos and increased knowledge concerning the control of powerful electric currents.
About 1879 dynamos began to be introduced into metallurgical practice, and from that date onwards numerous schemes for utilizing this cheaper source of energy were brought before theublic. The first electrical method worthy lectrical P y reduction.
Minor industries are represented by workshops for the production of surgical, musical and geodetic instruments; of telephone and telegraph accessories; dynamos, sewing-machines, bicycles and automobiles.
Following the nomenclature usual in connexion with dynamos we may speak of the conductors which carry the initial charges as the field plates, and of the moving conductors on which are induced the charges which are subsequently added to those on the field plates, as the carriers.