262 Experiments made ly the Galvanic Society of Paris. 



tions. The physical class of the society is charged to direct 

 its labours and experiments to this object. 



IT. 



In consequence of Dr. Baronio of Milan having pub-? 

 lished a description of a Galvanic pile formed of vegetable 

 matters, the society occupied themselves with ascertaining 

 the truth of Baronio's experiments. They procured sixty 

 even disks of walnut-tree wood, two inches in diameter, 

 furnished with a raised edge of about a line and a half, and 

 they boiled them in vinegar for some time. With these 

 disks and some rounds of raw beet-root, and radish, (Ra- 

 phanus sativus of Linnaeus) a pile was constructed of sixty 

 pairs of disks of beet-root and radishes, separated by disks 

 of wood ; upon the upper part of each of which, by means 

 of the border with which they were furnished, thev poured 

 acidulated tartrite of pota?h dissolved in vinegar ; they 

 afterwards placed at the lower extremity of the pile a leaf of 

 cochiearia, and at its upper extremity a double band of gray 

 paper soaked in vinegar. Every thing being thus disposed 

 agreeably to Baronio's detailed description, frogs properly 

 prepared were submitted to the action of the pile, by pla- 

 cing the leaf of cochiearia in communication with their 

 spinal marrow, and the band of paper with their muscles. 

 Three frogs successively subjected to repeated trials mani- 

 fested no kind of movement: after having made without 

 any success every trial capable of producing any effect, the 

 pile was placed in communication with the electro-micro- 

 meter without any effect ; the same instrument was after- 

 wards presented to a pendulous pile constructed after M. 

 Marechaux's method, composed of CO pairs of new disks 

 of copper and zinc, with the interposition of rounds of 

 pasteboard not moistened. A tension was experienced of 

 about ISO . At the same moment the frogs made use of 

 in the experiments with the vegetable pile were placed in 

 communication with the above pile, and they gave no signs 

 of sensibility. 



The Galvanic society, therefore, have not obtained the re- 

 sults indicated by Baronio ; but their experiments served to 

 convince them that the electro-micrometer, which they 



made 



