no 



ELECTRIC LIGHTING. 



The principle of Siemens' machines is based only on the 

 inductive reactions produced by the passage of the spires of 

 the multipliers before an electro-magnetic inducer, and under 

 the influence of a tangential motion. This is not precisely 

 the effect produced in Faraday's classic experiment, and the 

 direction of the currents produced is even different from 

 what it should be, according to the generally received no- 

 tions of induction. I have studied in detail these different 

 kinds of inductions in a paper presented to the Academic on 

 the 24th February, and the substance of this paper will be 

 found in Note A at the end of this volume. 



We have lately visited with much interest a large esta- 

 blishment which Siemens Brothers have organized in Paris, 

 at No. 8 Rue Picot, for the construction of those machines 

 under the management of Boistel. 



JablochkoflTs System. Jablochkoff has also con- 

 structed an induction machine with reversed currents, and 



with means for divid- 

 ing the light, which 

 is intended to admit 

 of being more easily 

 cleaned than the 

 Gramme machine, 

 and to work with less 

 motive power without 

 becoming heated. 

 For this purpose Jab- 

 lochkoff uses for in- 

 ducers a cast-iron 

 toothed wheel, hav- 

 ing the teeth slightly inclined to the direction of the axis, 

 and separated from each by a rather wide space. A coil 

 of wire winds between these teeth in the manner shown 

 in Fig. 36, and when this is traversed by a current the 

 teeth assume alternately opposite polarities, which convert 



