MAWSON & SWAN, 



Faraday's Rotating Needle, 7 6 

 Floating Batter}-, with solenoid, 6/- 

 Do. do. with circle of wire, 6 - 



Hittofs Apparatus, to illustrate the difference in the passage of the 

 electric spark through the ordinary atmosphere and through the 

 same rarefied, i8/- 



Magnet, capable of rotating about a current parallel to it, 2o/- 

 Magnet, Electro, revolving in a magnetised ring, 10/6 

 Magnet, Electro, to show the rotation of an electro-magnet between 

 the poles of a permanent horse-shoe magnet, i4/- 



Oersted's Apparatus, to show the action of an electric current upon 

 a magnetised needle, 5 6 



The same, the needle mounted on a rising pivot, the whole on 

 insulating stand with brass foot, 27/- 



FIG. 1 1 6. FIG. 117. 



Rheocord, Wheatstone's. for measuring electrical resistances, 257- 



(Fig. 117). 



Do. do. better finished, 42!- 



Resistance Coils of any kind to order, single bobbin, from 10 6 



Solenoid, for converting a bar of soft iron into a magnet by passage 

 of the current, 2/-, 6 -, and 10 - 



Vibrating Wire, Marsh's, 5;'- 



13 and 15, Mosley-street, Neivcastle-on-Tyne. 



