314 SEC. 10. ELECTRICITY. 



1324. Magneto-Electric Machine, to be worked by hand 

 or steam. La Societe V Alliance. 



This machine with eight bobbins is for the purpose of demonstration with 

 direct and alternate current, and can be worked by hand or steam. 



1325. Experimental Magneto-Electric Machine, the 



first constructed in which electricity and magnetism, rendered 

 active by the expenditure of mechanical force, were made to act 

 and re-act on one another in such a way as to greatly increase the 

 development of their forces. S. Alfred Varley. 



This machine was the first of its class, and acted on what was a new princi- 

 ple at the date of its construction. The new principle consisted in making 

 electricity and magnetism, rendered active by the expenditure of mechanical 

 force, act and re-act on one another in such a way as to greatly increase the 

 development of their forces. In this machine iron bobbins wrapped with 

 insulated wire are revolved between the poles of very feeble magnets made of 

 soft iron. The electricity (small in amount when the machine is first put in 

 motion) which is developed in the insulated wire of the bobbins passes, by 

 means of a commutator, through convolutions of insulated wire surrounding the 

 soft iron magnets, and renders them more highly magnetic. The magnetism 

 of the soft iron magnets being thus increased, develops a correspondingly 

 increased quantity of electricity in the revolving bobbins, which re-acts on the 

 soft iron magnets, rendering them still more highly magnetic. 



The expenditure of mechanical force giving motion to the machine is 

 greater as the magnetism and electricity developed increase, the consumption 

 of mechanical force having relation to the quantity of electricity rendered 

 active. 



1326. Gramme's Magneto-Electric Machine, for electro- 

 typing. H. Fontaine. 



1327. Gramme's Magneto-Electric Machine, for electric 

 light. H. Fontaine. 



1328. Gramme's Magneto-Electric Machine, for electric 

 light of great power. H. Fontaine. 



1329. Gramme's Magneto-Electric Machine, for demon- 

 stration. H. Fontaine. 



1315. Magneto-induction Machine. 



Gustav Baur, Stuttgart. 



This apparatus, containing several electro-magnets and a current re- 

 gulator, is furnished with double coils of wire, and may be used to set in 

 action electric apparatus of very various resistance and with very quick 

 interruption of current, e.g., Kuhmkorff coils. In general, any experiments 

 may be made with it that are made with batteries of 1-6 Bunseii elements. 

 It is suitable, for medical purposes, galvanocaustics, &c., and, if a part of 

 the rotating electro-magnets be wound with fine wire, for production of a 

 constant current up to 60 Meidinger elements. 



1330. M. lie Koiix's Electro-Magnetic Apparatus, for 



showing the effect of magnetism on copper discs. M. Ruhmkorff. 



