412 PHILOSOPHICAL TRANSACTIONS. IaNNO 1747. 



dinary accumulation of the electrical power in a phial of water, first discovered 

 by professor Muschenbroek. The experiment is, that a phial of water is sus- 

 pended to a gun-barrel by a wire let down a few inches into the water through 

 the cork; and this gun-barrel, suspended in silk lines, is applied so near an ex- 

 cited glass globe, that some metallic fringes inserted into the gun-barrel touch 

 the globe in motion. Under these circumstances a man grasps the phial with 

 one hand, and touches the gun-barrel with a finger of the other; on which he 

 receives a violent shock through both his arms, especially at his elbows and wrists, 

 and across his breast. 



That a gun-barrel is absolutely necessary to make this experiment succeed, is 

 imaginary; a solid piece of metal of any form is equally useful. Nor has he 

 yet found, that the stroke is in proportion to the quantity of electrified matter; 

 having observed the stroke from a sword as violent as that from a gun-barrel with 

 several excited iron bars in contact with it. 



He has tried the effect of increasing the quantity of water in the glasses of 

 different sizes, as high as 4 gallons, without in the least increasing the stroke. 

 If filings of iron be substituted instead of water, the effect is considerably lessened. 

 If mercury, much the same as water; the stroke is by no means increased in 

 proportion to their specific gravities, as might have been imagined. 



If a dry twig of birch, or any other wood, be run through the cork, instead 

 of the metallic wire, the stroke is not gi'eater than is usually felt from the gun- 

 barrel without the application of the water. The stroke is likewise lessened, if 

 the phial be held in the hand with a glove on. 



If you grasp the phial with your hand, and do not at the same time touch the 

 wire, the acquired electricity of the water is not diminished. So that, unless by 

 accident or otherwise the wire is touched, the electrified water will contain its 

 force many hours, may be conveyed several miles, and afterwards exert its force 

 on touching the wire. 



If, when any number of persons join hands, or communicate by any metallic 

 medium standing on the floor, one grasps the phial, and joins with the rest; on 

 the gun-barrel's being touched by the last person of the line, the whole number 

 are struck, and he who grasps the phial as forcibly as the rest. But if two phials 

 be employed, and he grasp them both, with a piece of wire of sufficient length 

 held between his fingers, which wire touches both phials, and its end be taken 

 hold of by the 2nd person of the line; if then the last person touch the excited 

 gun-barrel, all in the line are violently struck, except the person who grasps the 

 phials; but he feels little or nothing of the stroke. \ <«' imi> 



Mr. W. now proceeds to show by what steps, in his inquiries into the nature 

 of electricity, he discovered that the glass tubes and globes had not the electrical 

 power in themselves, but only served as the first movers and determiners of that 



