VOL. LXIX.] PHILOSOPHICAL TRANSACTIONS. 545 



by contact with water than the other inflammable airs do. However, I found 

 that in such a situation this air had not yet lost all its explosive force in 6 days, 

 though the water in which the cylindrical glass, 10 inches long and 1 in diame- 

 ter, was inverted, after I had poured into it 5 or 6 drops of aether, had gradually 

 ascended till, on the 3d day, it reached to the half of the height of the glass : 

 so that it seems as if these drops of aether, by their expanding in the form of 

 air, had forced out half of the common air contained in the glass, instead of 

 which the water afterwards ascended in proportion as the air or vapour generated 

 by the aether was absorbed by the water. 



That this air is specifically heavier than common air, and does not readily in- 

 corporate with it, is easily demonstrated by the following experiment. I poured 

 5 or 6 drops of aether into a cylindrical glass, 10 inches long, and 1 inch in 

 diameter : the aether being soon evaporated, I clapped my hand on the mouth 

 of the glass, and inverted it to incorporate the air generated by the aether with 

 the common air ; after which I left the glass open during half an hour, when I 

 dipped in it a piece of wax taper burning, stuck on a bended wire. As soon as 

 the taper reached the brim of tlie glass, a flame burst out with a weak explosion. 

 In a quarter of an hour I again thrust the wax taper into the same cylinder, and 

 no flame was observed till the wax taper reached the place where the flame ended 

 the first time. This 2d explosion did not set fire to the whole at the bottom of 

 the glass. I again waited a quarter of an hour, and then again thrust the wax 

 taper into it, by which the remainder of this inflammable gas, which had re- 

 mained settled all that time at the bottom, was exploded.* 



I found that aether, in which as much urinous phosphorus is dissolved as will 

 make it luminous in the dark, when some drops are poured on water, is very 

 brisk in taking fire, when employed for an inflammable air pistol ; but that the 

 experiment, when repeated, will be apt to fail, because the phosphoric acid 

 which remains in the pistol, and by its nature attracts the humidity of the at- 

 mosphere, will soon fill the inside of the pistol with a coat of moisture, and 

 prevent the electrical spark from kindling the inflammable air. It appeared, that 

 a little camphire dissolved in aether increases its explosive force, and makes it less 



* It is remarkable, tliat aether, tlie most volatile liquor yet known, and sa apt to spread itself 

 through tlie air by a quick evaporation that a drop of very fine aether, which falls from tlie height of 

 a few feet, is quite evaporated before it reaches the ground, and no glass stopper of itself is able to 

 keep it from evaporating : it is remarkable, I say, that notwithstanding this extreme voktility, the 

 air or vapour, into which it changes by evaporation, should be so far from participating of the same 

 volatility, that it may be kept hours togetlier in an open cylindrical vessel without evaporating, mixing 

 with tlie common air, or losing its inflammability ; so that this substance seems to undergo a sudden 

 metamorphosis, and to change in an instant from the lightest of all liquors to one of the heaviest of 

 aerial fluids, fixed air, which being one half heavier than common air, according to the experiments 

 of Mr. Cavendish, is probably much heavier than this aether air. — Orig. 



VOL. XIV, 4 A 



