illary tube. If a
piece of thermometer tubing, open at each end, be plunged into water, the
latter will instantly rise in the tube considerably above its external
level. If, on the other hand, the tube be plunged into mercury, a
repulsion instead of attraction will be exhibited, and the level of the
mercury will be lower in the tube than it is outside.]
[Footnote 5: Page 29. The late Duke of Sussex was, we believe, the first
to shew that a prawn might be washed upon this principle. If the tail,
after pulling off the fan part, be placed in a tumbler of water, and the
head be allowed to hang over the outside, the water will be sucked up the
tail by capillary attraction, and will continue to run out through the
head until the water in the glass has sunk so low that the tail ceases to
dip into it.]
[Footnote 6: Page 37. The alcohol had chloride of copper dissolved in it:
this produces a beautiful green flame.]
[Footnote 7: Page 54. Lycopodium is a yellowish powder found in the fruit
of the club moss (_Lycopodium clavatum_). It is used in fireworks.]
[Footnote 8: Page 58. Bunsen has calculated that the temperature of the
oxyhydrogen blowpipe is 8061 deg. Centigrade. Hydrogen burning in air has a
temperature of 3259 deg. C., and coal-gas in air, 2350 deg. C.]
[Footnote 9: Page 60. The following is the action of the sulphuric acid in
inflaming the mixture of sulphuret of antimony and chlorate of potassa. A
portion of the latter is decomposed by the sulphuric acid into oxide of
chlorine, bisulphate of potassa, and perchlorate of potassa. The oxide of
chlorine inflames the sulphuret of antimony, which is a combustible body,
and the whole mass instantly bursts into flame.]
[Footnote 10: Page 63. The "air-burner," which is of such value in the
laboratory, owes its advantage to this principle. It consists of a
cylindrical metal chimney, covered at the top with a piece of rather
coarse iron-wire gauze. This is supported over an argand burner, in such a
manner that the gas may mix in the chimney with an amount of air
sufficient to burn the carbon and hydrogen simultaneously, so that there
may be no separation of carbon in the flame with consequent deposition of
soot. The flame, being unable to pass through the wire gauze, burns in a
steady, nearly invisible manner above.]
[Footnote 11: Page 74. Water is in its densest state at a temperature of
39.1 deg. Fahrenheit]
[Footnote 12: Page 74. A mixture of salt and pounded
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