332 DYNAMO-ELECTRIC MACHINE. 



Next, Mr. Varley came forward with the assertion, 

 that already in the early part of the autumn of 1866 

 he had given orders to a mechanician for just such 

 an apparatus, and also subsequently handed in a 

 "provisional specification" of the same. My first 

 complete theoretical establishment of the principle in 

 the printed Transactions of the Berlin Academy, and 

 its previous practical elucidation, have however finally 

 been taken to be decisive in my favour. The name 

 given by me to the apparatus "dynamo-electric machine"' 

 has also become general, although frequently corrupted 

 in practice into "the dynamo". 



Already in my communication to the Berlin 

 Academy, I had pointed out that technical science was 

 now in possession of appliances capable of producing 

 electric currents of any desired tension and strength 

 by the expenditure of energy, and that this would 

 prove of great importance for many of its branches. 

 In fact large machines of the kind were immediately 

 constructed by my firm, one of which was exhibited 

 at the Paris Universal Exhibition of 1867, whilst a 

 second was employed in the summer of the same year 

 by the military authorities for electric lighting experi- 

 ments in Berlin. These experiments proved indeed 

 quite satisfactory, with the drawback, however, of the 

 wire-coils of the armatures rapidly becoming so hot, 

 that the electric light produced could only be allowed 

 for a short time without interruption. The machine 

 exhibited in Paris was never actually put to the test, 

 as there were no appliances for the transmission of 



