514 PHILOSOPHICAL TKANSACTIONS. [aNNO J 732. 



wood. This was screwed on to the upper end of one of the stands, formerly 

 mentioned, the other top being taken off; the dish was about 4 inches diameter, 

 and 1 i[)cl) deep. Then the stand was set on a cake of rosin, or a plate of 

 £rlass, or the brin)s of a drinking glass, or of a cylindric one, such as are used 

 for water glasses. The glass must be first warmed ; then the dish being filled 

 with water, the tube rubbed, and moved both under the dish and over the water 

 3 or 4 times, without touching them. After it has been excited, not only the 

 dish, but the water also, becomes electric; and if a small piece of thread, or a 

 narrow slip of thin paper, or a piece of sheet brass, commonly called tinsel, 

 be held over the water in a horizontal position, within about an inch or some- 

 times more, any of the said bodies will be attracted to the surface of the water, 

 and be repelled, but not so often as by solids. If a pendulous thread be held 

 at some distance from the outside of the dish, it will be attracted and repelled 

 by it many times together, with a very quick motion, but not at so great a dis- 

 tance as when the dish is empty. 



^^71 Experiment, shoiving that Water is attracted by the Tube, and that the 

 Attraction is attended ivith several remarkable and surprising Pho'nomena. — This 

 experiment being to be made with small quantities of water, Mr. Gray at first 

 made use of some of the brass concave little dishes in which he formerly ground 

 microscopes; but has since caused a more convenient apparatus to be made, 

 whicli consists of a small pedestal of about 4^- inches long, the base of ivory 

 about 2 inches diameter. On the upper end, as in the larger stand, there is a 

 screw, upon which is screwed one of the little ivory dishes; of which he has 

 several sizes, from three quarters to one-tenth of an inch diameter. When 

 any one of- these little vessels is filled with water, so that it may stand above 

 the brims of the cup, and has acquired a spherical surface, as it will do in the 

 smallest cups, let it be set on the table with the little stand to which it had 

 before been screwed, or, which is better, on the larger stand mentioned above, 

 the great dish being taken off, and the small plain top screwed on ; being thus 

 prepared, let the tube be excited, and held over the water at the distance of 

 about an inch or more. If it be a large tube, there will first arise a little moun- 

 tain of water from the top of the drop, of a conical form, from the vertex of 

 which there proceeds a light, very visible when the experiment is performed in 

 a dark room, and a snapping noise, almost like that when the fingers are held 

 near the tube, but not quite so loud, and of a more flat sound. On this im- 

 mediately the mountain falls into the rest of the water, and puts it into a tremu- 

 lous and waving motion. Having since repeated this experiment in the day- 

 time, where the sun shined, he perceived that there were small particles of 

 water thrown out of the top of the mount, and that sometimes there would 



