VOL. XLV.] PHILOSOPHICAL TRANSACTIONS. 473 



chalk, tobacco-pipe clay, or other such like materials, cast in moulds, so as to 

 represent real crabs'-eyes, are often substituted instead of them. 



BrevLi Historia Naturalis, she de f^ita, Genere, Morihusque Muris Alpini: 

 Autore Jacobo Theodoro Klein, Reipubl. Gedanens. N° 486, p. 180. 

 An account of the marmot, the natural history of which is now so well 

 known, as to render even an abstract of this paper unnecessary. 



Concerning Electricity. By the Abbe Nollet, F. R. S. and of the Royal Aca- 

 demy of Sciences at Paris. Translated from the French, by T. Stack, M. D., 

 F.R.S. N°486, p. 187. 



When a vessel full of liquor, which runs out through a pipe, is electrified, 

 the electrified jet or stream is thrown farther than usual, and is dispersed into 

 several divergent rays, much in the same manner as the water poured out from a 

 watering pot. Every body at first sight judges that the stream is accelerated, 

 and that the electrified vessel will soon be empty. Being unwilling to rely on 

 first appearances, M. N. resolved to ascertain the fact, by measuring the time, 

 and the quantity of the liquor running out. And in order to know if the acce- 

 leration, supposing there was any, was uniform, during the whole time of the 

 running out, he made use of vessels of different capacities, terminating in pipes 

 of different bores, from 3 lines diameter to the smallest capillaries; and the fol- 

 lowing contain in gross the result of upwards of a hundred experiments, as it is 

 not so easy a task to draw a safe conclusion, as may at first be imagined. 



1 . The electrified stream, though it divides, and carries the liquid farther, is 

 neither accelerated nor retarded sensibly, when the pipe, through which it issues, 

 is not less than a line in diameter. 2. Under this diameter, if the tube be wide 

 enough to let the liquid run in a continued stream, the electricity accelerates it 

 a little; but less than a person would believe, if he judged by the number of jets 

 that ar-e formed, and by the distance to which it shoots. 3. If the tube be a 

 capillary one, from which the water ought naturally to flow only drop by drop; 

 the electrified jet not only becomes continued and divided into several, but is also 

 considerably accelerated; and the smaller the capillary tube is, the greater in pro-, 

 portion is this acceleration. 4. And so great is the eftect of the electrical virtue, 

 that it drives the liquid out of a very small capillary tube, through which it had 

 not before the force to pass, and enables it to run out in cases where there would 

 not otherwise have been any discharge. 



These last facts have served as a basis to his inquiries. He considered all 

 organized bodies as assemblages of capillar)' tubes, filled with a fluid that tends 

 to run through them, and often to issue out of them. In consequence of this 

 idea, he imagined, that the electrical virtue might possibly communicate sdme 



VOL. IX. 3 P . 



