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THE CHEMICAL HISTORY OF A CANDLE.

of steam; and, on the contrary, the application of cold will contract that large quantity of steam into this small quantity of water. [One of the iron bottles burst at that moment.] Ah! There is one of our bottles burst, and here you see is a crack down one side an eighth of an inch in width. [The other now Fig. 13. exploded, sending the freezing mixture in all directions.] This other bottle is also broken; although the iron was nearly half-an-inch thick, the ice has burst it asunder. These changes always take place in water: they do not require to be always produced by artificial means,—we only use them here because we want to produce a small winter round that little bottle, instead of a long and severe one. But if you go to Canada, or to the North, you will find the temperature there out of