G64 



THE APPLICATIONS OF PHYSICAL FORCES. [BOOK v. 



wires of the helices, the current from the battery divided into two parts, 

 which respectively traversed in opposite directions the connected 

 helices, each through a semi-diameter of the ring, and finally left the 

 machine on the opposite side by a second roller, 7c, which was in con- 

 nection with the other pole of the battery. When the connections were 

 made, the iron ring began to rotate round its axis with considerable 

 force. In a trial in which the current was supplied by four small 

 elements of Bunsen, a weight of several kilogrammes was raised. In 

 the apparatus as actually constructed, the poles of the electro-magnet 



Fio. 434. Alliance mngneto-elertric madiiue. 



were enlarged by the addition of two segments of soft iron, A A, BB (Fig. 

 432), which extended over the greater part of the iron ring. The details 

 of the construction of the transversal electro-magnet will be easily 

 understood from the plan given .in the figure. 



The results he obtained were not great, but were sufficient to 

 enable him to announce that a magneto-electric machine could be 

 constructed which would have the advantage of giving the induced 

 currents all in the same direction, without the help of mechanical 

 arrangements to separate opposed currents or to make them conspire 

 with one another. 



