416 



NEGKETTI AND ZAMBEA, HOLBORN VIADUCT, E.G., 



2689 



2690 



2691 

 2692 

 2693 



2694 



2695 

 2696 



FIG. 2703. 



FIG. 2692. 



FIG. 2695. 



Marsh's Apparatus, for showing the vibration of a Sus- Each. 



pended Wire transmitting an electrical current when s . d. 



submitted to the influence of the poles of a magnet . 

 Faraday's Apparatus for showing the rotatory motion 



of a wire transmitting an electrical current round the 



pole of a magnet (fig. 2689) 



Faraday's Rotating Needle, and Marsh's Vibrating 



Wire, in the same instrument 



Terrestrial Rotating Magnet (fig. 2691) 

 Sturgeon's Rotating Disc (fig. 2692) . 

 Magnetometer (Sturgeon's), 4 to exhibit the properties of different 



metals under the influence of a powerful magnet 



Each. 



s. a. 

 10 6 



10 6 



15 

 14 

 15 



2 10 



FIG. 2694. 



Apparatus to 'exhibit the influence of a rotating Copper Disc upon 

 a magnet suspended above it, a thin sheet of parchment being placed 



between them (fig. 2694) 4 10 6 



Dr. Golden Bird's Vibrating Electro-magnet (fig. 2695) 2 10 



Barlow's Stellar-formed Rotating Wheel ... 10 



