128 PHILOSOPHICAL TRANSACTIONS. [^ANNO 1745. 



suspended in the chair, the motions of the heart and arteries are ver}' sensibly 

 increased ; and when a vein is opened under the operation, the blood that comes 

 from it appears lucid like phosphorus, and runs out faster than when the man is 

 not electrified. 



5. Water, in like manner, spouting from an artificial fountain suspended by 

 silk lines, scatters itself in luminous little drops ; and a larger quantity of water 

 is thrown out, in any given time, than when the fountain is not made electric. 



N.B. If 3, 4, or 5 globes be employed, the effect will be proportionably 

 better : and M. I'Abbe NoUet has found, that globes or tubes made of glass, co- 

 loured blue with zafFer, are preferable to others ; for when the glass is blue, the 

 experiments succeed in all weathers ; whereas in damp weather the white glass 

 loses much of its electric power. 



A Catalogue of 50 Plants from Chelsea Garden, presented to the Royal Society 

 by the Company of Apothecaries, for the Year \7 A3, pursuant to the Direction 

 of Sir Hans Sloarie, Bart., P. R. S. By Jos. Miller, Apothecary. N° 476, p. 42 1 . 

 [This is the 22d presentation of this kind, and completes the collection up to 



the number of 1 1 00 different plants.] 



An Inquiry into the Measure of the Force of Bodies in Motion : with a Proposal 

 of an Experimentum Crucis, to decide the Controversy about it. By James 

 Jurin, M.D., F.R.S. N° 476, p. 423. 



Mechanical forces may be reduced to 2 sorts ; one of a body at rest, the other 

 of a body in motion. The former is called by the name of pressure, tension, 

 force, or vis mortua ; and is measured by the weight of the body. 



The force of a body in motion is on all hands agreed to be a power residing in 

 that body, so long as it continues its motion ; by means of which it is able to 

 remove obstacles lying in its way ; to lessen, destroy, or overcome, the force of 

 any other moving body, which meets it in an opposite direction ; or to surmount 

 any dead pressure or resistance, as tension, gravity, friction, &c. for some time ; 

 but which will be lessened or destroyed by such obstacles, or by such resistance, 

 as lessens or destroys the motion of the body. This is called moving force, vis 

 motrix, and by some late writers, vis viva, to distinguish it from the vis mortua 

 spoken of before : and by these appellations, however different, the same thing 

 is understood by all mathematicians ; namely, that power of displacing obstacles, 

 withstanding opposite moving forces, or overcoming any dead resistance, which 

 resides in a moving body, and which, in whole or in part, continues to accom- 

 pany it, so long as the body moves. 



But about the measure of this kind of force, mathematicians are divided into 

 two parties : and, in order to state the case fairly between them, it will be ne- 



