Scientific American 8, 18.2.1860
This substance is principally derived from the cells of bees; wax being the mortar which those industrious creatures employ in the formation of their honey-combs. The wax if a bee.cell is of a yellowish brown color, and has a very pleasant odor. In its composition, it is a hydro-carbon of the same nature as tallow and spermaceti, and it has no equal for making beautiful and enduring candles, but they are too expensive for common purposes. To prepare wax for candles and ornamental moldings, such as wax figures (for which it is eminently adapted, owing to its unchanging character), it requires to be deprived of its brown color. For this purpose, the bee-cells are boiled in water several times, and strained through cloth, by which operations the impurities are removed. The finest wax is obtained from the skimmings of what are called "virgin combs." But these manipulations do not change the color of the wax. To do this, it is melted and drawn out into very thin ribbands, and these are laid either upon the grass or upon wobs of canvas, and exposed to sunlight, air and moisture, in the very same manner that linen used to be bleached by the old process. It takes several month to bleach wax by this system, but it is the best that is known, and it may be practiced by any person with a small quantity.
On a large scale, in manufactories, wax is first steamed in close vessels, then run out into thin strips from the bottom of a permornted pan, upon webs of canvas, and these are carried out to the "bleaching greens, " and exposed to the sunlight and air until bleached. The wax is sprinkled, from time to time, with soft water, to aid in bleaching, in exactly the same manenr as ivory is bleached. It might be supposed that chlorine gas, which has revolutionized the method of bleaching cotton and straw, would be applicable to wax, and that it would bleach it in as manhours as it takes months by the old process. This agent has been experimented with, but it injures the quality of the wax while bleaching.
The chlorine is liable to unite with the hydrogen of the wax, and form hydro-chloric acid, thereby changing its composition and injuring its illumination qualities. By submitting it to long exposure to high pressure steam, when in thin films, wax becomes nearly white; also, by boiling it in water, with about 25 per cent of sulphuric acid and the nitrate of soda. The wax must be thoroughly washed after being treated with acid in any manner. Some short and safe method of bleaching wax is a discovert much wanted. At present, the old method is the most generally practiced, because it is the only safe one. Wax tapers are not much employed in our country, but in France and some other European nations the manufacture of wax candles for religious ceremonies forms an immense business.
White wax may be colored blue with ultra-marine, reduced to an impalpable powder and thoroughly incorporated with it when melted. Verdigris, employed in the same manner, will color it green; carmine, a red, and chromate of lead, a bright yellow. Any of the common pigments will color wax. Steel and copperplate engravers employ common beeswax, mixed with Burgundy pitch to cover their plates preparatory to etching them. Wax is very preservative in its nature, and it was much used by the old painters for mixing their colors before the art of oil painting was discovered. It rendered their colors very durable, and it may now be employed with great advantage by all artists in colors. To descend to a more humble use, beeswax forms an excellent preservative of leather, when mixed with tallow or neats-foot oil. About one ounce to the pound of tallow, and the same amount to each pint of oil, is a great improvement to keep leather belting, boots and shoes in a soft, pliable and water-repelling condition.
Coloriasto on väriaiheisten tekstien (ja kuvien) verkkoarkisto
(Archive for colour themed articles and images)
INDEX: coloriasto.net
Ei kommentteja :
Lähetä kommentti