WILLIAM SIEMENS, F.R.S. 165 



stances that Mr. 8. Alfred Varley should be impatient to be con- 

 siili'ivd the whole and sole originator of the principle in question. 



But there is a circumstance connected with the provisional 

 specification itself which would lead one to suppose that at the 

 time of its being deposited in the Patent Office the Messrs. Varley 

 could not have submitted it to actual trial. They say, " Before 

 using the apparatus we generally send an electric current through 

 the electro-magnets ; the object of this is to secure a small amount 

 of permanent magnetism in the direction we wish in the soft iron 

 cores of the electro-magnets." A single trial of the apparatus 

 would have convinced those gentlemen that no such excitement 

 of the magnet is at all necessary for starting the apparatus in 

 action, terrestrial magnetism or a magnetic tension in the iron set 

 up in its manufacture being sufficient to engender the requisite 

 action. I am, however, not disposed to contest Mr. S. Alfred 

 Varley's assertion that the idea of the reaction principle occurred 

 to him in the autumn of 1866, and can only express my surprise 

 that he should have remained mute upon the subject until the 

 14th of December, 1867, when his final specification was filed, 

 which patent I need hardly say was invalidated through the 

 several prior publications which had at that time taken place. 



Yours faithfully, 



C. WILLIAM SIEMENS. 



12, QUEEN ANNE'S GATE, WESTMINSTER, Nov. 14, 1877. 



To THE EDITOR OF " ENGINEERING." 



SIR, Mr. Robert Sabine, in writing to you on the 28th 

 November, put the question of priority in conceiving the dynamo- 

 electrical reaction principle very tersely, and having conceded the 

 priority of publication to my brother, I should not have thought 

 it necessary to trouble you with any further remarks upon this 

 subject, if Mr. S. Alfred Varley had not lost sight of his avowed 

 intention of allowing the question to drop, by sending the letter 

 published in your last issue. 



Mr. S. Alfred Varley again brings forward as a proof of his 

 priority the bare fact of his having filed a provisional specification 



