ig6 PHILOSOPHICAL TRANSACTIONS. [anNO 1746. 



hand, or of the air in the room, the ice does not melt ; if so, every drop of water 

 from it considerably diminishes the received electricity. To obviate this, he 

 caused the assistant, while he was electrifying, to be continually wiping the ice 

 dry on a napkin hung to the buttons of his coat; and this being electrified as 

 well as the ice, prevented any loss of the force of the electricity. The experi- 

 ment will succeed likewise, if, instead of the ice, you electrify the spirit, &c. and 

 bring the ice not electrified near them. But ice is not so ready a conductor of 

 electricity as water. 



' In the first paper (Trans. N° 477) on this subject, Mr. W. took notice of 

 having observed 2 different appearances of the fire from electrified substances, viz. 

 those large bright flashes, which may be procured from any part of electrified 

 bodies, by bringing a non-electric unexcited near them, and with which we have 

 fired all the inflammable substances mentioned in the course of these observations ; 

 and those, like the firing of wet gunpowder, which are only perceptible at the 

 points or edges of excited non-electrics. These last also appear different in colour 

 and form, according to the substances from which they proceed: for, from 

 polished bodies, as the point of a sword, a silver probe, the points of scissars, and 

 the edges of the steel bar made magnetical by the ingenious Dr. Knight, the 

 electrical fire appears like a pencil of rays, agreeing in colour with the fire from 

 Boyle's phosphorus; but from unpolished bodies, as the end of a poker, a rusty 

 nail, or such-like, the rays are much more red. These pencils of rays issue suc- 

 cessively, as long as the bodies, from which they proceed, are exciting; but they 

 are longer and more brilliant, if any non-electric not excited be brought near 

 them, though it must not be close enough to make them snap. By holding a 

 hand at about 2 or 3 inches distance from these points, you not only feel suc- 

 cessive blasts of wind from them, but hear also a crackling noise. Where there 

 are several points, you observe at the same time several pencils of rays. 



It appears from experiments, that besides the several properties that electricity 

 is possessed of peculiar to itself, it has some in common with magnetism and 

 light. 



Prop. 1. — In common with magnetism, electricity counteracts, and in light 

 substances overcomes the force of gravity. Like that extraordinary power like- 

 wise, it exerts its force in vacuo as powerfully as in open air, and this force is 

 extended to a considerable distance through various substances of different 

 textures and densities. 



Carol. — Gravity is the general endeavour and tendency of bodies towards the 

 centre of the earth : this is overcome by the magnet, with regard to iron, and by 

 electricity, with regard to light substances, both in its attraction and repulsion. 

 But he has never been able to discern that vortical motion, by which this effect 

 was said to be brought about by the late Dr. Desaguliers and others, Jxaving ncb 



