432 FRAGMENTS OF SCIENCE. 



But the discovery which, above all others, brought 

 the practical question to the front is now to be con- 

 sidered. On the 4th of February, 1867, a paper was 

 received by the Eoyal Society from Dr. William Sie- 

 mens bearing the title, ' On the Conversion of Dynamic 

 into Electrical Force without the use of Permanent 

 Magnetism/ * On the 14th of February a paper from 

 Sir Charles Wheatstone was received, bearing the title, 

 ' On the Augmentation of the Power of a Magnet by 

 the Eeaction thereon of Currents induced by the Mag- 

 net itself.' Both papers, which dealt with the same 

 discovery, and which were illustrated by experiments, 

 were read upon the same night, viz. the 14th of Feb- 

 ruary. It would be difficult to find in the whole field 

 of science a more beautiful example of the interaction 

 of natural forces than that set forth in these two pa- 

 pers. You can hardly find a bit of iron you can hardly 

 pick up an old horse-shoe, for example that does not 



Trinity House on May 17, 1866: 'It gives me pleasure to state 

 that the machine is exceedingly effective, and that it far tran- 

 scends in power all other apparatus of the kind.' 



* A paper on the same subject, by Dr. Werner Siemens, was 

 read on January 17, 1867, before the Academy of Sciences in Ber- 

 lin. In a letter to 'Engineering,' No. 622, p. 45, Mr. Robert Sa- 

 bine states that Professor Wheatstone's machines were constructed 

 by Mr. Stroh in the months of July and August. 1866. I do. not 

 doubt Mr. Sabine's statement ; still it would be dangerous in the 

 highest degree to depart from the canon, in asserting which Fara- 

 day was specially strenuous, that the date of a discovery is the 

 date of its publication. Towards the end of December, 1866, Mr. 

 Alfred Varley also lodged a provisional specification (which, I 

 believe, is a sealed document) embodying the principles of the 

 dynamo-electric machine, but some years elapsed before he made 

 anything public. His brother, Mr. Cromwell Varley, when writ- 

 ing on this subject in 1867, does not mention him (Proc. Roy. 

 Soc., March 14, 1867). It probably marks a national trait, that 

 sealed communications, though allowed in France, have never 

 been recognised by the scientific societies of England. 



