Charcoal

“ One solitary instance has been quoted, in which a manufacturer of great intelligence has obtained by the use of charcoal, from a very pure ore, a union of both these valuable properties, and another, in which iron as soft as that made with coke, has been produced by means of charcoal. ”

“ The absorption of lime by animal charcoal depends, in all probability, in a great degree on the mineral component parts of bone charcoal.
[11] Charcoal is a very bad conductor of heat, and therefore forms an excellent insulator or packing to prevent the transmission of heat. A charcoal lining is often used in crucibles for heating many substances, as it does not melt and resists a far greater heat than many other substances. ”

“ Wood charcoal is made by heating wood in closed vessels or in large masses, when all the hydrogen, oxygen, and nitrogen are expelled in the gaseous state, and the carbon is left mixed with the mineral constituents of the wood ”

“ A variety of animal charcoal is sometimes prepared by calcining fresh blood with potassium carbonate in large cylinders, the mass being purified by boiling out with dilute hydrochloric acid and subsequent reheating. Wood charcoal is a hard and brittle black substance, which retains the external structure of the wood from which it is made. ”

“ One of the most remarkable of these is, that it is not liable to decay by age. Hence it was customary, with the ancients, to char or burn the outside of stakes, or other wood, which were to be driven into the ground, or placed in water. Charcoal may be preserved without injury for an almost indefinite length of time; and, in the ancient tombs of the inhabitants of northern nations, entire pieces of charcoal are at this day frequently discovered. ”

“ Charcoal varies in its qualities according to the substance from which it is prepared: that of the soft woods (willow or alder) is best for crayons and gunpowder; that of the hard woods for fuel, and for blowpipe supports. That made by a low red heat, not exceeding cherry red, and which has a dull surface, is the most valuable. ”

“ When properly prepared, charcoal exhibits very distinctly the rings of annual growth which may have characterised the wood from which it was formed. It is very light in consequence of its porous nature, and it is wonderfully indestructible.
But its greatest, because it is its most useful property, is undoubtedly the power which it has of absorbing great quantities of gas into itself. It is in fact what may be termed an all-round purifier. It is a deodoriser, a disinfectant, and a decoloriser. It is an absorbent of bad odours, and partially removes the smell from tainted meat. ”

“ To obtain the charcoal contained in vegetable or animal substances, we subject them to the action of fire, at first moderate, and afterwards very strong, on purpose to drive off the last portions of water, which adhere very obstinately to the charcoal. ”

“ Indeed, charcoal, which is impure carbon, might be obtained by strongly heating either a handful of corn, or a piece of fowl’s flesh, in a vessel from which the air is excluded so as to keep the corn or the flesh from burning. ”

“ We must not overlook the fact that there is another form of charcoal, namely, animal charcoal or bone-black. This can be obtained by heating bones to redness in closed iron vessels. In the refining of raw sugar the discoloration of the syrup is brought about by filtering it through animal-charcoal ”

“ Upon these small holes all the cooking is done; the charcoal is fanned into a glow with a feather fan, and if there are many pots and saucepans they must take their turn upon the tiny fires. Scuttles do not exist, and the stock of charcoal for use is kept on the floor beneath the range. ”

“ There are two methods of working in charcoal—one, in which the charcoal point is used alone, the shading being put in with lines which are not blended, no stump, or rubbing together of any kind being allowed. ”

“ Charcoal is made by burning wood in such a manner that but little air shall be admitted during the operation, that is to say, only sufficient to keep up the combustion of the more easily destroyed parts of the wood, leaving a black residue called charcoal. ”

“ Then what wonderful properties do we find in charcoal, which is so brittle that a light tap breaks it and a slight pressure pulverizes it, and yet is so strong that no moisture rots it, nor any time causes it to decay. ”

“ For it is very dry, wherefore it sputters as it burns; whereas wood for charcoal should contain sap.
The best charcoal comes from trees in their prime, and especially from trees which have been topped [3] : for these contain in the right proportion the qualities of closeness admixture of mineral matter and moisture. Again better charcoal comes from trees [4] in a sunny dry position with a north aspect than from those grown in a shady damp position facing south. Or, if the wood [5] used contains a good deal of moisture, [6] it should be of close texture; for such wood contains more sap. ”

“ Charcoal is well known to everybody, although it is no easy matter to obtain it in a chemically pure state. Pure charcoal is a simple, insoluble, infusible, combustible substance produced by heating organic matter, and has the familiar aspect of a black mass, devoid of any crystalline structure, and completely insoluble. Charcoal is a substance possessing a peculiar combination of physical and chemical properties. This substance, whilst in a state of ignition, combines directly with oxygen; in organic substances it is found in combination with hydrogen, oxygen, nitrogen, and sulphur. ”

“ Charcoal is extensively employed as a fuel; and in metallurgy for tempering metals, making steel, &c.; reduced to powder, it is used to surround vessels and bodies required to retain their heat for some time; a coating of charcoal, formed on piles and stakes of wood by charring them, promotes their preservation. Fresh burnt charcoal, in coarse powder, restores tainted meat and putrid water, discolours vegetable solutions, deodorises fetid substances, and withdraws lime from syrups filtered through it. ”

“ Carbon forms a considerable part of the solid matter of all organised bodies; but it is most abundant in the vegetable creation, and it is chiefly obtained from wood. When the oil and water (which are other constituents of vegetable matter) are evaporated, the black, porous, brittle substance that remains, is charcoal.
CAROLINE.
But if heat be applied to the wood in order to evaporate the oil and water, will not the temperature of the charcoal be raised so as to make it burn; and if it combines with oxygen, can we any longer call it pure? ”

“ The admixture of charcoal with the soil, is said to be a means of adding to its nutritive qualities. Charcoal, which is nearly pure carbon, may be supposed continually to give off a portion of this gaseous substance during its decomposition, and this uniting with a portion of the oxygen contained in the air, would furnish a supply of carbonic acid gas, to the atmosphere immediately about the plants. ”

“ Charcoal, the third allotropic modification of carbon, is by far the most common, and is formed by the natural or artificial disintegration of organic matters by heat; we thus have formed wood charcoal, animal charcoal, lamp-black, and coke, all produced by artificial means, and we may also class with these coal, which is a natural product, and which contains from 85 to 95 per cent. ”

“ Charcoal, or a Vegetable burnt black, affords an object no less pleasant than instructive, for if you take a small round Charcoal, and break it short with your fingers, you may perceive it to break with a very smooth and sleek surface, almost like the surface of black sealing Wax; this surface, if it be look’d on with an ordinary Microscope, does manifest abundance of those pores which are also visible to the eye in many kinds of Wood, rang’d round the pith, both a in kind of circular order, and a radiant one. ”

“ The unalterability of charcoal under the action of atmospheric agencies, which produce changes in the majority of stony and metallic substances, is often made use of in practice. For example, charcoal is frequently strewn in boundary ditches. The surface of wood is often charred to render it durable in those places where the soil is damp and wood itself would soon rot. ”

“ Stoves for house warming are not used in dwellings in these countries.
In both China and Japan we saw coal dust put into the form and size of medium oranges by mixing it with a thin paste of clay. Charcoal is similarly molded, as seen in Fig. 72, using a byproduct from the manufacture of rice syrup for cementing. In Nanking we watched with much interest the manufacture of charcoal briquets by another method. A Chinese workman was seated upon the earth floor of a shop. By his side was a pile of powdered charcoal, a dish of rice syrup byproduct and a basin of the moistened charcoal powder. ”

“ The most porous charcoal is very light; a cubic metre of wood charcoal weighs about 200 kilograms. Many of the properties of charcoal which depend exclusively on its porosity are shared by many other porous substances, and vary with the density of the charcoal and depend on the way it was prepared. The property which charcoal has of absorbing gases, liquids, and many substances in solution, is a case in point. The densest kind of charcoal is formed by the action of great heat on sugar and other fusible substances. The lustrous grey dense coke formed in gas retorts is also of this character. ”

“ Oils, spirits, various extracts, and vegetable and other solutions are filtered through charcoal in order to purify them. The bleaching power of charcoal may be tested by using various coloured solutions—such as aniline dyes, litmus, &c. Charcoal, which has absorbed one substance to saturation is still capable of absorbing certain other substances. Animal charcoal, produced in a very finely-divided state, especially by heating bones, makes the best sort for the purposes of absorption. ”

“ As it is difficult to separate from the charcoal the admixture of ash—that is, the earthy matter contained in the vegetable substance used for producing charcoal—in order to obtain it in its purest condition it is necessary to use such organic substances as do not contain any ash, for example completely refined or purified crystallised sugar, crystallised tartaric acid, &c. ”

“ Finally, the iron, now covered with a thin layer of steel, is hardened by quenching it in water. In default of prussiate of potash, animal or even vegetable charcoal may be used, but the latter is a very imperfect substitute. To make animal charcoal, take a scrap of leather, hide, hoof, horn, flesh, blood--anything, in fact, that has animal matter in it; dry it into hard chips like charcoal, before a fire, and powder it. Put the iron that is to be case-hardened, with some of this charcoal round it, into the midst of a lump of loam. ”

“ A brilliant example of the acted charade is described in Thackeray’s Vanity Fair.
CHARCOAL, the blackish residue consisting of impure carbon obtained by removing the volatile constituents of animal and vegetable substances; wood gives origin to wood-charcoal; sugar to sugar-charcoal; bone to bone-charcoal (which, however, mainly consists of calcium phosphate) ; while coal gives “coke” and “gas-carbon.” The first part of the word charcoal is of obscure origin. ”

“ To-day charcoal is made commercially by piling wood on steel cars and then pushing the cars into strong walled chambers. The chambers are closed to prevent access of air, and heated to a high temperature. The intense heat transforms the wood into charcoal in a few hours. A student can make in the laboratory sufficient charcoal for art lessons by heating in an earthen vessel wood buried in sand. The process will be slow, however, because the heat furnished by a Bunsen burner is not great, and the wood is transformed slowly. ”

“ Charcoal is frequently carried by travellers in sacks; they use a prepared charcoal in the East, which is made in the form of very large buttons, that are carried strung together on a string. An Indian correspondent informs me that they are made by mixing powdered charcoal with molasses, in the proportion of ten to one, or thereabouts, rolling the mass into balls, and drying them in the sun. A single ball is called a "gul." They are used for igniting hookhas: they are also burnt inside the smoothing-iron used by washermen in order to heat it. ”

“ The charcoal should be perfectly pure and in a finely divided state, for if adulterated with any gritty matter (and sometimes such is the case) a very indifferent working material is produced, the evil results of which show themselves in every stage of manufacture. ”

“ I am sorry for the charwardar, one leg is evidently gone.
Some hundred mules now in the caravanserai, noise of their bells all night long; country fertile, lots of villages all down the valley; we passed several on our left only.
In lighting the kalian or water-pipe, the way of preparing burning charcoal on the road without a fire, and with speed and economy, is ingenious; a light is put to a bit of charcoal, that is placed in a wire basket the size of one’s fist among other pieces of charcoal ”

“ The true coal consists principally of the flattened bark of sigillaroid and other trees, intermixed with leaves of ferns and Cordaites, and other herbaceous débris, including vast numbers of spores and spore cases, and with fragments of decayed wood constituting "mineral charcoal," all their materials having manifestly alike grown and accumulated where we find them. ”

“ The mineral charcoal or ‘mother coal’ is obviously woody tissue and fibres of bark, the structure of the varieties of which, and the plants to which it probably belongs, I have discussed in the paper above mentioned. ”

“ While there is no lack of authority to prove the value of animal charcoal as a filtering material, the claims of vegetable charcoal seem to me to make it more serviceable. Vegetable charcoal is "the solid residuum of the destructive distillation of wood." It is insipid and inodorous, it is insoluble in water, it is but little affected by either acids or alkalies. The ash consists chiefly of carbonate of potash, silica, lime, and the oxide of iron. Vegetable charcoal has a strong deodorizing power. ”