J ^--^ij- 



Figure 2. — Galvani's experiments in animal electricity. From Luigi Galvani, 

 De Viribus Eledricitatis in Motu Musculari Commentarius , Bologna, 1791, trans- 

 lated by Margaret Foley, Norwalk, Connecticut, 1953, pi. 4. 



effects if more or larger plates were used; but, of 

 course, the heavier the plates, the faster the paper 

 dried out and the faster the pile ceased working. Such 

 dehydration could be avoided by dividing the pile in 

 half and connecting several piles together. Even so, 

 the pile usually was effective for only a couple of days; 

 then it had to be taken apart and cleaned before fur- 

 ther use. Such devices (fig. 5) were in use during the 

 first quarter of the 1 9th century. Volta devised a bat- 

 tery with a longer life in his "crown of cups." ^ This 

 innovation consisted of a number of cups filled with a 

 saline solution and with a pair of dissimilar metals in 

 each cup. One metal electrode was joined to its oppo- 

 site mate in the next cup, and so on, until a complete 

 circuit was made. However, the "crown of cups" was 

 much bulkier than the pile. 



Volta' s results were communicated in two well 

 known letters to England, where they promptly stim- 

 ulated further work. Even before the publication of 

 the second letter, William Nicholson and Anthony 

 Carlisle made a pile of 17 silver half-crowns and as 



many zinc disks. ^ This pile was not powerful enough 

 for their electrocheinical experiments, so they made 

 another pile of 36 pairs, and then one of 100 pairs.'' 

 Dissatisfied with the arrangement of the metals in 

 a pile, William Cruickshanks devised his "trough" 

 battery.* For this battery, 60 pairs of zinc and silver 

 plates measuring about m inches square were 

 cemented with rosin and beeswax in a trough so 

 that all the zinc plates faced one way and all the 

 silver plates the other way. The cells formed by 

 these metal partitions were "charged" by a dilute 

 solution of ammonium chloride. Trough batteries 

 (such as shown in figs. 6-8) might last several weeks 

 instead of only a couple of days, but even so the 



5 Ibid. 



6 William Nicholson, "Account of the New Electrical or 

 Galvanic Apparatus of Sig. Alex. Volta, and Experiments 

 Performed with the Same," Journal of Natural Philosophy, 

 Chemistry, and the Arts (hereinafter referred to as Nicholson's 

 Journal), 1800, vol. 4, pp. 179-187. 



' William Nicholson, Anthony Carlisle, William Cruick- 

 shanks, et al. "Experiments in Galvanic Electricity," Philo- 

 sophical Magazine, 1800, vol. 7, pp. 337-^347. 



s William Cruickshanks, "Additional Remarks on Galvanic 

 Electricity," Nicholson's Jowrna/, 1801, vol. 4, pp. 254-264. 



PAPER 28: DEVELOPMENT OF ELECTRICAL TECHNOLOGY IN THE 19TH CENTURY: I 



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