Although M. Champonois thinks, as we have just remarked, that the slices thus impregnated with the residual wash, are nearly equal in nutritive value to the original root, there are many reasons for thinking otherwise. The true nature of nutrition is as yet but imperfectly understood, and mere chemical explanations, in the sense in which that term is now understood, do not account for all the phenomena; assuming that to be the case, however, there can be no doubt of this, that there is no use of supplying an animal with such an excess of any one ingredient of its food, that under no conditions could it assimilate it. Or in other words, that there must be a certain relation between the constituents of an article of food, and any excess of any one of them will be useless, if not injurious. Now if a distillation of beet-juice be well conducted, the residual wash will contain almost nothing dissolved but the soluble salts, the greater part of the nitrogenous constituents being nearly in a state of suspension. In saturating the sliced root with this liquor, we are simply saturating them with a saline solution; but a simple calculation will show that such saline substances are not necessary to such an extent for animals, and that the efforts of agriculturists ought rather to be directed to diminish than to increase the quantity of saline substances in plants. The quantity of soluble salts in one day's food of beet is fully equal to the quantity which a cow would require to assimilate in two days, and if the roots be large, the excess may be doubled or trebled. It is therefore questionable whether, allowing the residual wash to settle, in order to collect the rich nitrogenous substances, and pouring off the saline liquor, and employing only pure water for the maceration, would not yield as good a food for cattle as that proposed by M. Champonois's process above described. By the latter process the fuel required for heating the liquor for maceration would be economized, as the wash would be run directly from the still upon the sliced roots, whilst where water would be employed, although this economy would not be effected, the macerated slices would not have so loosening an action upon the cattle, owing to the removal of the large excess of salts.

Another objection may be made to the process of a purely economical character, namely, how far is it advisable to join manufacturing operations of a complicated kind with the business of agriculture? Experience derived from other branches of industry are certainly not favourable to such a junction. It is not, however, our intention at present to discuss any of these objections, our object now being simply to direct public attention to the importance of the subject for this country, and to guide those, of whom there are many in Ireland, who have at various times attempted the manufacture of beet-spirit, by teaching them what has been done in France, where the problem has been, in our opinion, completely solved. In a future number we shall return to this subject again, with the object of providing our readers with a short treatise upon the most approved system of manufacture, and the economical conditions under which it may be successfully carried out.

ART. IL-Method of rapidly bleaching Wax, and purifying Tallow,

Oils, &c.

WAX, properly speaking, consists of pure wax and a colouring matter; there are several kinds of wax, distinguished commercially by the relative amount of colouring matter which they contain. Formerly it was supposed that wax could only be bleached by the action of sunlight; to effect this object the operations could only be commenced in the month of May, when the fine season has set in, and the sun attained sufficient altitude to send its rays more directly for a longer period and with more force; and these conditions continue only at most for three or four months. To bleach wax by this process, it must be made into ribands of great tenuity, or feathered as zinc is by being poured into water; an operation which must be repeated at least three times, whilst the duration of the exposure to the sunlight must occupy from one month to six weeks, in order to destroy the colouring matter to which we have alluded. To do this requires a considerable space, which is often very expensive, and a heavy outlay in plant, such as bleaching frames, canvass, &c.; this primitive condition of the wax industry renders the bleaching not only embarrassing, but uncertain and variable according to the weather.

In order to diminish the amount of capital which was required to be sunk in this branch of trade, and, above all, to shorten the time required to bleach the wax, M. Cassgrand, some years ago, patented a process in France, which has now passed into the public domain, and which, it appears, has been very successful.

This process consists in melting the wax by means of steam, until it becomes very liquid, and then passing it, along with the steam, through a kind of serpentine or worm, by which a large surface becomes exposed to the action of the steam. After traversing the worm it is received in a pan with a double bottom heated by steam, where water is added in order to wash it; from this it is elevated by a pump, kept hot by steam, into another pan similarly heated, and where it is also treated with water, and is again passed through the serpentine. This operation is repeated twice, thrice, or four times, according to the quality of the wax; during the passage with the steam through the worm, it becomes denser by, it is said, absorbing water (perhaps mechanically?), and deposits in the upper pan. It is allowed to repose in this for about four or five minutes after each passage; and after the last one, about one or two hours, according to quantity, in order to allow of any impurities to subside. The wax is then granulated in the ordinary way by means of cold water, is allowed to dry during two or three days, and the action of light and air does the rest, for which one person is sufficient. The whole of the operations do not require more than a few days, are perfectly certain, and are attended with no danger. Independent of the advantage which such an apparatus has for bleaching wax, it has also that of enabling its qualities, according to relative whiteness, to be distinguished; for this purpose it is only necessary to present the wax in mass to the end of the worm, and in a second or two the vapour mines the relative colour which it will yield.

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This process is also applicable to the purification of tallows and of oils; even fish oil, when passed through the apparatus of M. Cassgrand, and washed as just described, is completely deprived of its disagreeable smell; and if it be set aside in a place where the temperature only reaches from 59° to 68° Fahr., a fresh deposit will form, and the oil will become perfectly clarified and nearly colourless.

This process has considerable analogy with one which Mr. Dixon, of this city, patented some time since for bleaching palm oil; the principle of which was exposing the oil to the action of steam. Cassgrand's apparatus might, no doubt, be applied to the same purpose, and appears to us to have certain advantages over that of Dixon, especially in exposing a larger surface to the action of the steam, and varying that surface oftener. If not already known here, the process is worthy of the serious attention of soapboilers. Such a method would evidently be much more effective than the present system of purifying cils, especially where sulphuric acid is used, which is almost universally the case. As that acid is scarcely ever effectively removed, many samples of trotter, rape, and other similar oils, are usually quite acid; where the former is used for the manufacture of hair oil, it is very destructive to the hair, and the latter destroys the lamps when used for burning, &c. The only modification required for the purification of oil would be to divide the oil as much as possible by means of a diaphragm of copper, pierced with holes, in the first steam vessel, and thus expose the largest possible surface to the action of the steam in flowing through the pierced diaphragm into the worm.-See Le Génie Industriel, No. 38, vol. vii., p. 72.

ART. III.—On the uses to which Turf might be applied in Ireland. No. 2.

PEAT CHARCOAL.

In our last number we directed attention to a new and novel application of peat to the manufacture of paper, papier maché, and carton pierre, and we now purpose to make some observations upon another of its applications, the value of which is already fully appreciated by the public, although but seldom taken advantage of; namely, the manufacture of peat charcoal for deodorizing purposes.

From some remarks which we have seen lately in the newspapers, it would appear that an impression prevails that this application of peat charcoal is protected by patent. This we doubt, because already, many years ago, the distinguished Irish chemist Richard Kirwan suggested this use of peat mould and semi-charred peat for absorbing fetid liquids; and peat charcoal has been employed to some extent for such purposes in Paris for a period of more than twenty years. A patent has been obtained for a peculiar process of preparing it, and probably this led to the notion that no one could make it, for the special purpose of using it as a deodorizer, but the patentee. The manufacture of peat charcoal is therefore open to any

body who is willing to embark in it; and the greater the number is who do so, the greater will be the probability of success, for the demand would be almost unlimited, if the supply were regular, and the article could be sold at a reasonable price.

Porous bodies, and especially charcoal, have the property of absorbing gases, in certain proportions depending upon the nature of the porous substance and of the gas. For example, wood charcoal, when freshly prepared, will absorb 90 times its own bulk of ammonia, but only 1 times its bulk of hydrogen. In the same way porous bodies absorb liquids, a familiar example of which is offered in the common sponge. Freshly prepared peat charcoal is capable of absorbing from 120 to 170 per cent. of its bulk of water, and yet form a more or less solid mass, from which water will not drain; consequently, one ton of charcoal will take up nearly two tons of fetid water, and form only a pasty mass. No matter how putrescent the water may be previous to being mixed with the charcoal, all smell will disappear. If more fetid water be poured upon the pasty mass of water and charcoal, the latter not being able to absorb it, the water will filter through, but in its passage will be fully deprived of all disagreeable odour. A bed of peat charcoal will therefore act as a filter for purifying sewerage water, and will completely prevent the escape of unwholesome and stinking effluviæ. The action of peat charcoal is not confined to gases and liquids; even solid putrescent matter, if mixed with it, is almost instantaneously deprived of smell.

The quantity of charcoal which is sufficient to produce any of the effects just mentioned is comparatively small, so small indeed that no difficulty can arise as to its use upon this account.

In most cities and towns the provisions made to get rid of the excrementitious matter, the sewerage water, the waste from factories, &c., is most defective, and especially in those parts where business is most active, and space consequently more valuable. In many of those places the soil is impregnated with decaying organic matter, or the house is surrounded by or covers one or more cess-pools, which are constantly generating noxious gases and effluviæ, which, by their combined action upon the body, lower its vitality, and render the inhabitants extremely liable to catch epidemic and contagious diseases. It is impossible to conceive any thing more disgusting, for example, than the provisions made in some houses for privies and water-closets, most of which, when they exist at all, are mere receptacles for filth, without exit, except by soaking into the surrounding soil, and reeking with pestilential exhalations, while they are being filled up in the course of years. In such places the general use of peat charcoal would be attended with the greatest benefit to the public health. And even where the most perfect system of sewerage may exist, its use would be equally valuable, by preventing the polluted drainage liquid of a city being poured into the rivers.

Who that has visited an hospital, no matter how well kept, that is not sensible that much more might be done to render the air pure and free from disagreeable odours, and thus conducive to the health of the inmates. We are fully convinced that fresh air, light, and cleanliness, are quite as

useful remedies in all diseases as the most powerful medicines; but unfortunately they are not so generally prescribed as they should be. Among the many ways by which hospitals may be kept in a proper condition, the extensive use of peat charcoal would be perhaps the most effective. It is needless to point out any further applications, as they are already well known to our readers, or will suggest themselves to every one, bearing in mind the deodorizing properties of the substance. The uses to which we have alluded will, however, bear out our statement, that the demand for it, if the supply were regular and at a moderate cost, would be unlimited. Before, however, coming to the object of this paper, which is the mode of meeting that demand, or, more properly speaking, of creating it, we must allude to another proposed application of peat charcoal, for the purpose of correcting some opinions held with regard to it, and which we deem erroneous; namely, the employment of peat charcoal as a manure.

Without denying that peat charcoal may have some action as a manure, we are convinced that its value in that respect has been greatly exaggerated. A substance can only act as a manure in two ways-mechanically or chemically. To act in the former capacity very large quantities must be employed. If some twenty or thirty tons of peat charcoal were mixed with the superficial layer of soil of an acre of land, it might perhaps produce a perceptible influence upon the physical properties of the soil; but any one who has ever seen two tons of charcoal sprinkled upon the same area, will at once admit that such a quantity could produce no perceptible influence upon the physical character of the soil. The chemical influence of a manure is judged by the absolute amount of certain constituents which it contains, and also by the peculiar condition or state of combination in which they exist. Our information as to the relative value of each ingredient is no doubt very defective, and on this account no absolute judgment can be pronounced upon the absolute manuring value of any substance. Certain general principles have, however, been established, and these enable us to ascertain approximately the relative manuring value of a substance, or at least sufficiently so to be of great practical use.

The first element in the value of a manure, whether considered in its mechanical or chemical character, is its cost. This is quite intelligible; for a manure may be very valuable at 5s. per ton, and worthless if it could not be sold for less than £1 per ton. Now this is exactly the case with peat charcoal; it contains in its ash many valuable constituents, but the price at which it has hitherto been sold is more than double what the same substances could be purchased for in other forms. When peat charcoal is mixed with night-soil, or other similar substances, in the proportion of two of charcoal and one of night-soil or even of equal parts, the value of the mixture, estimated on the same principles as are usually applied in the case of guano, would not be more than 15s., or at the utmost, £1 per ton. At least we have seen no samples, the analyses of which would warrant the assumption of a higher value.

Hitherto the prices charged for peat charcoal have been such, that the sum realized by the manure produced, if estimated at its true value, would not be sufficient to cover the original outlay for the charcoal.

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