474 PHILOSOPHICAL TRANSACTIONS. [aNNO 1747-8. 



motion to the sap of vegetables, and also augment the insensible perspiration of 

 animals. He began by some experiments, the result of which confirmed his 

 notions. He electrified, for 4 or 5 hours together, fruits, green plants, and 

 sponges dipped in water, which he had carefully weighed ; and he found, that after 

 this experiment, all these bodies were remarkably lighter than others of the same 

 kind, weighed with them, both before and after the experiment, and kept in the 

 same place and temper. He also electrified liquors of all sorts in open vessels; 

 and he remarked, that the electrification augmented their evaporation, in some 

 more, in others less, according to their differ natures. Therefore he took two 

 garden-pots, filled with the same seeds; he kept them constantly in the same 

 place, and took the same care of them, except that one of the two was elec- 

 trified for 1 5 days running, for 2 or 3, and sometimes 4 hours a day. This pot 

 always showed its seeds raised 2 or 3 days sooner than the other, also a greater 

 number of shoots, and those longer, in a given time : which shows that the elec- 

 trical virtue helps to open and display the germs, and facilitates the growth of 

 plants. 



He chose several pairs of animals of different kinds, cats, pigeons, chaffinches, 

 sparrows, &c. and put them all into separate wooden cages, and then weighed 

 them. He electrified one of each pair for five or six hours together: then weighed 

 them again. The cat was commonly 65 or TO grains lighter than the other; the 

 pigeon from 33 to 38 grains, the chaffinch and sparrow 6 or 7 grains: and in or- 

 der to have nothing to charge on the difference that might arise from the tern 

 perament of the individual, he again repeated the same experiments, by electri- 

 fying that animal of each pair, which had not been electrified before; and not- 

 withstanding some small varieties which happened, the electrified animal was con- 

 stantly lighter in proportion than the other. 



1 Electricity therefore increases the insensible perspiration of animals: but in 

 what proportion? Is it in the ratio of their bulks, or in that of their surfaces? 

 neither the one nor the other, strictly speaking, but in a ratio much more approach- 

 ing to the latter than to the former. So that there is no room to apprehend that a 

 human person electrified would lose near a 50th part of his weight, as it hap- 

 pened to one sort of bird; nor the 140th part, as to the pigeon, &c. All that 

 he had been hitherto able to learn on this head, was, that a young man or woman, 

 from 20 to 30, being electrified during 5 hours, lost several ounces of their 

 weight, more than they were wont to lose, when they were not electrified. These 

 last experiments are difficult to pursue with exactness; because the clothing, 

 which cannot strictly be compared to the hair or feathers of animals, retains a 

 good share of the perspired matter, and hinders us from forming a good judgment 

 of the whole effect of the electrical virtue. 



This forced electric perspiration is very naturally accounted for, if we consider, 



