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Faraday, Michael, 1791-1867

"The Chemical History of a Candle"

Water is a thing compounded of two
substances, one of which we have derived from the candle, and the other we
shall find elsewhere. Water may occur as ice; and you have had most
excellent opportunities lately of seeing this. Ice changes back into
water--for we had on our last Sabbath a strong instance of this change, by
the sad catastrophe which occurred in our own house, as well as in the
houses of many of our friends,--ice changes back into water when the
temperature is raised: water also changes into steam when it is warmed
enough. The water which we have here before us is in its densest
state[11], and although it changes in weight, in condition, in form, and
in many other qualities, it still is water; and whether we alter it into
ice by cooling, or whether we change it into steam by heat, it increases
in volume,--in the one case very strangely and powerfully, and in the
other case very largely and wonderfully. For instance, I will now take
this tin cylinder, and pour a little water into it; and seeing how much
water I pour in, you may easily estimate for yourselves how high it will
rise in the vessel: it will cover the bottom about two inches. I am now
about to convert the water into steam, for the purpose of shewing to you
the different volumes which water occupies in its different states of
water and steam.


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