Although, according to Cadet, this contrivance cannot be depended upon, as the appearances it presents are not regular; yet, as the effect is produced by heat, as well as light and electricity, the following summary may be added:
1. In fair weather, the composition remains at the bottom, and the liquor is clear.
2. Before rain, it will rise a little; the liquor will be clear, having merely a star floating in it.
3. Before a storm, it will rise to the surface, the liquor will appear troubled. These appearances may be seen 24 hours before the change in the weather takes place.
4. In winter, it is higher than common. During a snow, it will be very white, and pieces are seen in motion.
5. In settled weather in summer, and when warm, the composition will be low.
6. To know from what quarter wind will come, the composition will remain attached on the opposite side of the bottle to that from which it is expected.
Camphor has been burnt, like ether and alcohol, by platinum wire, previously heated. Dr. Ure observes, that a cylinder of camphor may be used for both wick and spirit, in the aphlogistic lamp; and the ignition is very bright, while an odoriferous vapour is exhaled. By adding various essential oils in small quantities to the alcohol of the lamp, various aromas may be made to perfume the air of an apartment. See [Scented Fires for rooms.]
Camphor is employed in those fire-works chiefly, which are exhibited in rooms; its expense being an objection to its use in large exhibitions. In what are termed perfumed pastes, or mixtures, scented fire, or odoriferous fire-works, it is used in abundance: in fact, it enters into nearly all the compositions of this kind. Camphor, besides producing, alone, a white flame, gives a brilliant light, and, when mixed with other substances, adds greatly to the appearance of the flame; and, giving out a powerful odour, destroys, in a measure, the disagreeable smell arising from the combustion of the sulphur and nitre.