MEMOIR OF PELTIER. 



165 



subject of the quantity aud intensity of currents, lie publislaed a resume of liis 

 works on tliis subject, in volume 63 of tbe Annals of Chemistry and Physics. 



January 9th, 1837, Peltier presented to the Academy of Sciences a large work 

 containing his experimental researches into the various phenomena which concur 

 in producing the general result from electric piles ; the 30th of the same month 

 he inserted a note on the dynamic electricity engendered by friction. May 15 

 he made known to the academy the new hygrometer he had just invented, and 

 his work on solutions and dissolutions; and, finally, on June 12, he laid before 

 this same learned body his researches on the difference in the conduction of a 

 circuit according to the direction of the current ; and thus explained from natural 

 causes a fact that M. De la Rive could not account for, except by admitting, in 

 electric currents, interferences analogous to those of light. 



In 183S Peltier published in volume 67 of the Annals of Chemistry and Physics 

 an article on the quantity of dynamic and static action produced by the oxida- 

 tion of a milligram of zinc, and on the relation which exists between these two 

 kinds of phenomena. Faraday had handled an analogous question before Pel- 

 tier, and M. Becquerel has treated it since. These three gentlemen have arrived 

 at this conclusion : that a dynamic degree represents an enormous static force ; in 

 other words, that a galvanometer, despite its apparent sensibility, is an extremely 

 inert instrument compared with the electroscope. This same year Peltier made 

 known the cause of secondary currents in liquids ; and he published in the Annals 

 of Natural Science two dissertations : one on a new kind of floscularia, the other 

 on the structure of muscles. He also laid before the Philomathic Society his 

 observations on the zoosperms of the frog ; on magnetism by discharges along a 

 bar ; on the displacement of the axis of a magnetic needle during a prolonged 

 deviation, &c., &c. 



In the beginning of 1839, Peltier presented to the Philomathic Society an 

 article containing most interesting observations on the difference in structure of 

 the motor and sensitive nerves. At the same time he published in volume 71 of 

 the Annah of Chemistry and Physics a very comprehensive dissertation. This 

 dissertation is composed of two distinct parts : the first treats of the formation of 

 tables in regard to relations which exist between the force of an electric cun'ent 

 and the deviation of the needles of the multipliers — and certainly no one was 

 more fit than Peltier to do this work ; the second treats of the causes of pertur- 

 bation in the thermo-electric pairs and the means of avoiding it. It is in itself 

 an entire and profouiul study of thermo-electricity. Peltier examines in this 

 work the effect of the bulk of the pairs and their number, of the size of the 

 solderings, the extent of surface immersed, &c. 



During the period we have just sketched, Peltier had also occupied himself 

 with the study of meteorology, although in a cursory manner. In 1835 he placed 

 on the house he occupied apparatus for studying the temperature and electric 

 state of distant media. The apparatus with which he at this time studied the 

 electric interchange between the earth and clouds was as follows : it was formed 

 of a piece of copper wire suiTounded with silk, and covered over with several 

 layers of oil varnish ; the upper portion of this wire was terminated by a tuft of 

 platina wire, and was elevated about 25 metres above the earth ; the lower end 

 was also tenninated by a platina wire, and immersed in a deep well of 12 metres. 

 In the midst of the wire Peltier interposed at pleasure either a multipiier of 

 3,000 coils, an electrometer of his invention, or a simple electroscope of gold 

 leaves. By the aid of this apparatus Peltier soon ascertained that the earth ordi- 

 narily gave indications of negative electricity; that, in general, there was a nega- 

 tive ascending current, but that in certain circumstances, and especially during 

 storms, there was on the contrary very often an inverse current, that is, a nega- 

 tive descending current. 



Later, in 1836, Peltier ascertained that during storms the negative ascending 

 current acquired at times a considerable force, and then ceased altogether, giving 



