IREK CALORIC.

78

MRS. B.

That is true; but in this case it will evaporatebut very slowly. I am going to show you howsuddenly the ether in this phial will be convertedinto vapour, by means of the air-pump,—Observewith what rapidity the bulrWcs ascend, as I takeoff the pressure of the atmosphere.

CAROLINE.

It positively boils: how singular to see a liquidboil without heat!

MRS. B.

Now I shall place the phial of ether in thisglass, which it nearly fits, so as to leave only asmall space, which i fill with water; and in thisstate I put it again under the receiver. (PlateIV. Fig. 6.)*—You will observe, as I exhaust theair from it, that whilst the ether boils, the waterfreezes.

• Two pieces of thin glass tubes, sealed at one end, might an-swer this purpose better, The experiment, however, as heredescribed, is difficult, and requires a very nice apparatus. But if,instead of phials or tubes, two watch glasses be used, water maybe frozen almost instantly in the same manner. The two glassesa«e placed over one another, with a few drops of water inter-posed between them, and the uppermost glass is filled with ether.After working the pump for a minute or two, the glasses arefound to adhere strongly together, and a thin layer of ige is seenbetween them.