996 Transactions of the American Institute. 



find a 'communication from M. Masson towards the close of the 

 year 1837, in the Annales de Chemie, vol. 6Q, page 28, on this sub- 

 ject, in which he refers to his '' Memoir e" to the French Academy, 

 in June, 1835, as containing the substance of his paper. We also 

 find, in the Comptc Rendu, 1837, a report of M. M. Becquerel and 

 Savary of the Seance of 27th of March, 1836, on the memoir of 

 M. xMasson, which they state was received soon after the discoveries 

 of Faraday on the induction of a current on itself, were made 

 known in Paris. This is somewhat indefinite; but as these dis- 

 coveries were published in the latter part of 1834 and beginning 

 of 1835, we may be safe in taking the date of June, 1835, for M. 

 Masson's experiments. Becqnerel's report mentions the coil of 1,400 

 feet of wire, the use of a number of pairs of Wollaston battery, 

 and the toothed wheel circuit-breaker. Also the production of 

 shocks of suflicient power to kill a cat. It is probable, therefore, 

 that M. Masson preceded Dr. Neef, and that he was the first to 

 obtain secondary currents of high intensity from a primary circuit 

 by using an intensity battery, and to use a mechanical circuit-breaker 

 in connection with the coil. M. Masson, in concluding his paper 

 referring to the publication of Dr. Neef s experiments, says they 

 were " made subsequent to his own." M. Masson's toothed wheel 

 was revolved by a pulley, band and multiplying wheel. He did 

 not employ a secondary circuit, and the great length of his circuit 

 wire and extended batteries rendered the whole too -cumbrous for 

 medical uses. 



• In 1836 Prof. Page communicated to Silliman^s Journal, vol. 

 31, page 137, a description of an induction apparatus; an engravuig 

 is given of the apparatus, and on reading the description it is found 

 to be distinct from any which preceded it, in several important 

 particulars. It announces the interesting and very important dis- 

 covery that the "shock is very much increased by breaking the 

 circuit over mercury covered with water or with naphtha." A 

 description is given of two mechanical circuit-breakers for producing 

 a rapid succession of shocks — one made of a rasp, and the other a 

 revolving spur-wheel. A postscript to the article, dated " Salem, 

 June, 1836," describes an automatic circuit-])reaker, consisting of 

 Barlow's spur-wheel included in the circuit. It mentions the 

 "charging of a Leyden jar by the secondary curf-ent," and the decom- 

 position of water, together with several other novel and interesting 

 experiments. But the most important feature of novelty is that 

 of "increasing shocks," as the caption indicates, hy the use of a 



