136 



A comparison between the power of the new machine 

 and that of the 10 inch machine will show that while the 

 current from the former fuses 12 feet of iron wire 0-075 of 

 an inch in diameter, the current from the latter fuses only 

 7 feet of wire 0-065 of an inch in diameter ; and is, con- 

 sequently, only about half as powerful as that from the new 

 machine. Besides this, the quantity of copper used in the 

 construction of the new machine is about 3|cwt., and of iron 

 locwt. ; while the weight of these metals in the 10 inch 

 machine is 29cwt. and 60cwt. respectively. In other words, 

 we have in the new machine a double amount of power, 

 with less than one-fourth the amount of materials employed 

 in the construction of the 10 inch machine. Another 

 advantage possessed by the new machine is the great 

 reduction of temperature in the armatures by their rapid 

 motion through the air, which acts much more efficiently 

 than the circulation of water through the magnet cylinder. 

 By increasing the diameter of the electro-magnetic circles, 

 conjointly with the number of electro-magnets and arma- 

 tures, the angular velocity of the machine may be so 

 diminished that it may be driven directly from the crank 

 of a steam engine, concurrently with an increase of electric 

 power proportionate to the number of electro-magnets and 

 armatures in the electro-mao^netic circles. 



In his paper "On a Property of the Magneto-electric 

 Current to Control and Render Synchronous the Rotations 

 of the Armatures of a number of Electro-magnetic Induction 

 Machines,"* the author stated that this property would be 

 available when the machines were used for the electro-deposi- 

 tion of metals from their solutions. It has, however, been 

 found that the small resistance presented by depositing solu- 

 tions to the passage of the currents, prevents this property 

 from manifesting itself (in accordance with what the author 



* Proceediugs of the Literary aud Philosophical Society of Manchester, 

 December 15th, 18G8. 



