DISCOURSE OF W. B. TAYLOR. 239 



and Geology. These occupations left him no leisure for the pursuit 

 of original research. He subsequently gave lectures on Astronomy, 

 and also on Architecture. 



In 1834, Henry constructed for the Laboratory of his College 

 an original form of galvanic battery; so arranged as to bring into 

 action any desired number of elements, from a single pair to eighty- 

 ciglit. Each zinc plate 9 inches wide and 12 inches deep was sur- 

 rounded by a copper case open at top and bottom, and giving thus 

 one and a half square feet of efficient surface. Eleven of these, in 

 eleven separate cells, formed a sub-battery; and eight of these were 

 grouped together by means of adjustable conductors, so as to form 

 from the whole a single battery. By means of a crank and windlass 

 shaft in proper connection, any one or more of the eight sub-batteries 

 could be immersed or disengaged, and if desired, a single cell alone 

 could be charged. By another arrangement of adjustable conduct- 

 ors, all the zinc plates could be directly connected together, and all 

 the copperplates together, after the plan of Dr. Hare's "calori- 

 motor" battery; thus giving the "quantity" effect due to a single 

 element of 132 square feet of zinc surface, or of any smaller area 

 desired. As the author remarks concerning its various arrange- 

 ments, " they have been adopted in most cases after several experi- 

 ments and much personal labor." A detailed account of this battery 

 was given in a communication read January 16th, 1835, before the 

 American Philosophical Society (of which he had recently been 

 elected a member), and was published in its Transactions.* 



Electrical Self-Induction. — Meanwhile he had been engaged in 

 his brief intervals of relaxation from his exacting professional cares 

 during the past year, in repeating and extending his interesting obser- 

 vations (commenced at Albany in 1832), on the remarkable intensi- 

 fying influence of a long conductor, and especially of a spiral one, 

 when interposed in a galvanic circuit of a single pair, or a battery 

 of low "intensity." A verbal communication on this curious form 

 of "induction," was made to the Society on the same occasion as 

 the description of his battery, and was illustrated by experiments 

 exhibited before the Society. ' 



♦ IVans. Am. PhUos. Soc. vol. v. (u. s.) art. Ix. pp. 217-222. 



