To Boil Water Without Fire.
Half fill a common oil-flask with water, and boil it for a few minutes over the flame of a spirit-lamp. While boiling, cork up the mouth of the flask as quickly as you can, and tie a bit of wet bladder over the cork, so as to exclude the air perfectly. The flask being now removed from the lamp, the boiling ceases. Pour some cold water upon the upper portion of the flask, and the ebullition recommences! Apply hot water, and it stops! And thus you may go on as long as you please.