nd place it under a jar, and then put a light on the
other side, just to shew you what is going on. You see that the sides of
the jar become cloudy, and the light begins to burn feebly. It is the
products, you see, which make the light so dim, and this is the same thing
which makes the sides of the jar so opaque. If you go home and take a
spoon that has been in the cold air, and hold it over a candle--not so as
to soot it--you will find that it becomes dim, just as that jar is dim. If
you can get a silver dish, or something of that kind, you will make the
experiment still better. And now, just to carry your thoughts forward to
the time we shall next meet, let me tell you that it is _water_ which
causes the dimness; and when we next meet. I will shew you that we can
make it, without difficulty, assume the form of a liquid.
LECTURE III.
PRODUCTS: WATER FROM THE COMBUSTION--NATURE OF WATER--A
COMPOUND--HYDROGEN.
I dare say you will remember that when we parted we had just mentioned the
word "products" from the candle. For when a candle burns we found we were
able, by nice adjustment, to get various products from it. There was one
substance which was not obtained when the candle was burning properly,
which was charcoal or smoke; and there was some other substance that went
upwards from the flame which did not appear as smoke, but took some other
form, and made part of that general current which, ascending from the
candle upwards, becomes invisible, and escapes. There were also other
products to mention. You remember that in that rising current having its
origin at the candle, we found that one part was condensable against a
cold spoon, or against a clean plate, or any other cold thing, and another
part was incondensable.
We will first take the condensable part, and examine it; and, strange to
say, we find that that part of the product is just water--nothing but
water. On the last occasion I spoke of it incidentally, merely saying that
water was produced among the condensable products of the candle; but
to-day I wish to draw your attention to water, that we may examine it
carefully, especially in relation to this subject, and also with respect
to its general existence on the surface of the globe.
Now, having previously arranged an experiment for the purpose of
condensing water from the products of the candle, my next point will be to
shew you this water; and perhaps one of the best means that I can adopt
fo
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