Figure 5. — Kemp's voltaic pile of 1828. From 

 Edinburgh New Philosophical Journal, 1828, 

 vol. 6, pi. 2, p. 71. 



Figure 4. — Reproduction of voltaic pile of 

 about 181 o. The stand is about 4 feet high. 

 {USNM ^!jo4g; Smithsonian photo ^7048-D.) 



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