Miscellanies. 39^ 



MISCELLANIES. 



DOMESTIC AND FOREIGN. 



1. On the use of Carhon in Grove's Battery. — Some months since, 

 being engaged in experiments with Grove's flat-celled battery, some of 

 the prominent defects of form, construction and expense seemed to me to 

 be remediable, by another mode of construction, and the use of a cheap- 

 er negative element. About the same time, I learned that Berzelius had, 

 in a letter to Dr. Hare, given an account of a battery where coke was 

 at once the negative element and the containing vessel for the nitric acid. 



I have since made many experiments, and now give the result which 

 seems most promising. Natural plumbago, or the mixture of it with sand, 

 such as is used in the manufacture of crucibles, gives the form of carbon 

 which is at once the most effective, cheap and manageable. A battery 

 was constructed of six cylindrical members of native plumbago, each ele- 

 ment one inch in diameter and two inches high, placed in nitric acid of 

 the commercial strength, contained in a cylindrical cup of porous queen's 

 ware, and opposed by a circular zinc element amalgamated. The con- 

 nection was formed by a wire dipping from each zinc into a mercury 

 cup excavated in the top of the plumbago cylinders. This battery of six 

 members gave results which were highly satisfactory. In decomposing 

 power, it accomplishes more than 100 pairs of zinc and copper of 6 

 inches square each. It gave 5 cubic inches of the mixed gases of wa- 

 ter in less than 50 seconds, or 1 cubic inch in 12 seconds. It also main- 

 tained for nearly an hour, at full incandescence, 14 inches of No. 30 

 platina wire, coiled into a spiral. In all other modes of exhibition it 

 shows a proportionate power. 



I am now constructing a batteiy of large series on this plan, and 

 when the results are obtained will publish them more at length. I would 

 remark to those who may be interested in constructing similar batteries, 

 that plumbago is easily obtained from Sturbridge, Mass., of a compactness 

 very suitable for batteries ; and moreover, that (as before remarked) 

 the mixed plumbago* of the manufacturers of " black lead" ware, an- 

 swers very well. The porous cells used in my experiments have been 

 made at Jersey City, N. J. B. Silliman, Jr. 



Yale College Laboratory, Sept. 12, 1842. 



2. Elirenherg's Notices of American Infusoria. — On the 25th of 

 March, 1841, M. Ehrenberg made a communication to the Royal Acad- 

 emy at Berlin, in which he referred to specimens of American fossil 



* To be obtained of J. W. Ingall, Taunton, Mass. 

 Vol. XLiii, No. 2— July-Sept. 1842. 50 



