Chapter 6

One great bar to previous success would appear to have been the absence of exact knowledge as to the nature of the constituents of that portion of the plant which contains the fiber, or, in other words, the casing or bark surrounding the woody stem of the rhea. As determined by Professor Fremy, this consists of the cutose, or outer skin, within which is the vasculose containing the fiber and other conjoined matter, known as cellulose, between which and the woody stem is the pectose, or gum, which causes the skin or bark, as a whole, fiber included, to adhere to the wood. The Professor, therefore, proceeded to carefully investigate the nature of these various substances, and in the result he found that the vasculose and pectose were soluble in an alkali under certain conditions, and that the cellulose was insoluble. He therefore dissolves out the cutose, vasculose, and pectose by a very simple process, obtaining the fiber clean, and free from all extraneous adherent matter, ready for the spinner.

In order, however, to insure as a result a perfectly uniform and marketable article, the Professor uses various chemicals at the several stages of the process. These, however, are not administered haphazard, or by rule of thumb, as has been the case in some processes bearing in the same direction, and which have consequently failed, in the sense that they have not yet taken their places as commercial successes. The Professor, therefore, carefully examines the article which he has to treat, and, according to its nature and the character of its components, he determines the proportions of the various chemicals which he introduces at the several stages. All chance of failure thus appears to be eliminated, and the production of a fiber of uniform and reliable quality removed from the region of doubt into that of certainty. The two processes of M. Favier and M. Fremy have, therefore, been combined, and machinery has been put up in France on a scale sufficiently large to fairly approximate to practical working, and to demonstrate the practicability of the combined inventions.

The experimental works are situated in the Route d'Orleans, Grand Montrouge, just outside Paris, and a few days ago a series of demonstrations were given there by Messrs. G.W.H. Brogden and Co., of Gresham-house, London. The trials were carried out by M. Albert Alroy, under the supervision of M. Urbain, who is Professor Fremy's chief assistant and copatentee, and were attended by Dr. Forbes Watson, Mr. M. Collyer, Mr. C.J. Taylor, late member of the General Assembly, New Zealand, M. Barbe, M. Favier, Mr. G. Brogden, Mr. Caspar, and a number of other gentlemen representing those interested in the question at issue. The process, as carried out, consists in first treating the rhea according to M. Favier's invention. The apparatus employed for this purpose is very simple and inexpensive, consisting merely of a stout deal trough or box, about 8 ft. long, 2 ft. wide, and 1 ft. 8 in. deep. The box has a hinged lid and a false open bottom, under which steam is admitted by a perforated pipe, there being an outlet for the condensed water at one end of the box. Into this box the bundles of rhea were placed, the lid closed, steam turned on, and in about twenty minutes it was invariably found that the bark had been sufficiently softened to allow of its being readily and rapidly stripped off by hand, together with the whole of the fiber, in what may be called ribbons. Thus the process of decortication is effectively accomplished in a few minutes, instead of requiring, as it sometimes does in the retting process, days, and even weeks, and being at the best attended with uncertainty as to results, as is also the case when decortication is effected by machinery.

Moreover, the retting process, which is simply steeping the cut plants in water, is a delicate operation, requiring constant watching, to say nothing of its serious inconvenience from a sanitary point of view, on account of the pestilential emanations from the retteries. Decortication by steam having been effected, the work of M. Favier ceases, and the process is carried forward by M. Fremy. The ribbons having been produced, the fiber in them has to be freed from the mucilaginous secretions. To this end, after examination in the laboratory, they are laid on metal trays, which are placed one above the other in a vertical perforated metal cylinder. When charged, this cylinder is placed within a strong iron cylinder, containing a known quantity of water, to which an alkali is added in certain proportions. Within the cylinder is a steam coil for heating the water, and, steam having been turned on, the temperature is raised to a certain point, when the cylinder is closed and made steam-tight. The process of boiling is continued under pressure until the temperature--and consequently the steam pressure--within the cylinder has attained a high degree.

On the completion of this part of the process, which occupies about four hours, and upon which the success of the whole mainly depends, the cementitious matter surrounding the fiber is found to have been transformed into a substance easily dissolved. The fibrous mass is then removed to a centrifugal machine, in which it is quickly deprived of its surplus alkaline moisture, and it is then placed in a weak solution of hydrochloric acid for a short time. It is then transferred to a bath of pure cold water, in which it remains for about an hour, and it is subsequently placed for a short time in a weak acid bath, after which it is again washed in cold water, and dried for the market. Such are the processes by which China grass may become a source of profit alike to the cultivator and the spinner. A factory situate at Louviers has been acquired, where there is machinery already erected for preparing the fiber according to the processes we have described, at the rate of one ton per day. There is also machinery for spinning the fiber into yarns. These works were also visited by those gentlemen who were at the experimental works at Montrouge, and who also visited the Government laboratory in Paris, of which Professor Fremy is chief and M. Urbain _sous-chef_, and where those gentlemen explained the details of their process and made their visitors familiar with the progressive steps of their investigations.

With regard to the rhea treated at Montrouge, we may observe that it was grown at La Reolle, near Bordeaux. Some special experiments were also carried out by Dr. Forbes Watson with some rhea grown by the Duke of Wellington at Stratfield-saye, his Grace having taken an active interest in the question for some years past. In all cases the rhea was used green and comparatively freshly cut. One of the objects of Dr. Watson's experiments was, by treating rhea cut at certain stages of growth, to ascertain at which stage the plant yields the best fiber, and consequently how many crops can be raised in the year with the best advantage.

This question has often presented itself as one of the points to be determined, and advantage has been taken of the present opportunity with a view to the solution of the question. Mr. C.J. Taylor also took with him a sample of New Zealand flax, which was successfully treated by the process. On the whole, the conclusion is that the results of the combined processes, so far as they have gone, are eminently satisfactory, and justify the expectation that a large enterprise in the cultivation and utilization of China grass is on the eve of being opened up, not only in India and our colonies, but possibly also much nearer home.

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APPARATUS FOR HEATING BY GAS.

This new heating apparatus consists of a cast iron box, E, provided with an inclined cover, F, into which are fixed 100 copper tubes that are arranged in several lines, and form a semi-cylindrical heating surface. The box, E, is divided into two compartments (Fig. 5), so that the air and gas may enter simultaneously either one or both of the compartments, according to the quantity of heat it is desired to have. Regulation is effected by means of the keys, G and G', which open the gas conduits of the solid and movable disk, H, which serves as a regulator for distributing air through the two compartments. This disk revolves by hand and may be closed or opened by means of a screw to which it is fixed.

Beneath the tubes that serve to burn the mixture of air and gas, there is placed a metallic gauze, I, the object of which is to prevent the flames from entering the fire place box. These tubes traverse a sheet iron piece, J, which forms the surface of the fire place, and are covered with a layer of asbestos filaments that serve to increase the calorific power of the apparatus.

The cast iron box, E, is inclosed within a base of refractory clay, L, which is surmounted by a reflector, M, of the same material, that is designed to concentrate the heat and increase its radiation. This reflector terminates above in a dome, in whose center is placed a refractory clay box. This latter, which is round, is provided in the center with a cylinder that is closed above. The box contains a large number of apertures, which give passage to the products of combustion carried along by the hot air. The carbonic acid which such products contain is absorbed by a layer of quick-lime that has previously been introduced into the box, N.

This heating apparatus, which is inclosed within a cast iron casing similar to that of an ordinary gas stove, is employed without a chimney, thus permitting of its being placed against the wall or at any other point whatever in the room to be heated.--_Annales Industrielles_.

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IMPROVED GAS BURNER FOR SINGEING MACHINES.

Since the introduction of the process of gas-singeing in finishing textiles, many improvements have been made in the construction of the machines for this purpose as well as in that of the burners, for the object of the latter must be to effect the singeing not only evenly and thoroughly, but at the same time with a complete combustion of the gas and avoidance of sooty deposits upon the cloth. The latter object is attained by what are called atmospheric or Bunsen burners, and in which the coal gas before burning is mixed with the necessary amount of atmospheric air. The arrangement under consideration, patented abroad, has this object specially in view. The main gas pipe of the machine is shown at A, being a copper pipe closed at one end and having a tap at the other. On this pipe the vertical pipes, C, are screwed at stated intervals, each being in its turn provided with a tap near its base. On the top of each vertical table the burner, IJ, is placed, whose upper end spreads in the shape of a fan, and allows the gas to escape through a slit or a number of minute holes. Over the tube, C, a mantle, E, is slipped, which contains two holes, HG, on opposite sides, and made nearly at the height of the outlet of the gas. When the gas passes out of this and upward into the burner, it induces a current of air up through the holes, HG, and carries it along with it. By covering these holes with a loose adjustable collar, the amount of admissible air can be regulated so that the flame is perfectly non-luminous, and therefore containing no free particles of carbon or soot. The distance of the vertical tubes, C; and of the fan-shaped burners is calculated so that the latter touch each other, and thus a continuous flame is formed, which is found to be the most effective for singeing cloth. Should it be deemed advisable to singe only part of the cloth, or a narrow piece, the arrangement admits of the taps, D, being turned off as desired.--_Textile Manufacturer_.

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SILAS' CHRONOPHORE.

In many industries there are operations that have to be repeated at regular intervals, and, for this reason, the construction of an apparatus for giving a signal, not only at the hour fixed, but also at equal intervals, is a matter of interest. The question of doing this has been solved in a very elegant way by Mr. Silas in the invention of the apparatus which we represent in Fig. 1. It consists of a clock whose dial is provided with a series of small pins. The hands are insulated from the case and communicate with one of the poles of a pile contained in the box. The case is connected with the other pole. A small vibrating bell is interposed in the circuit. If it be desired to obtain a signal at a certain hour, the corresponding pin is inserted, and the hand upon touching this closes the circuit, and the bell rings. The bell is likewise inclosed within the box. There are two rows of pins--one of them for hours, and the other for minutes. They are spaced according to requirements. In the model exhibited by the house Breguet, at the Vienna Exhibition, there were 24 pins for minutes and 12 for hours. Fig. 2 gives a section of the dial. It will be seen that the hands are provided at the extremity with a small spring, r, which is itself provided with a small platinum contact, p. The pins also carry a small platinum or silver point, a. In front of the box there will be observed a small commutator, M, (Fig. 1). The use of this is indicated in the diagram (Fig. 3). It will be seen that, according as the plug, B, is introduced into the aperture to the left or right, the bell. S, will operate as an ordinary vibrator, or give but a single stroke.

P is the pile; C is the dial; and A is the commutator.

It is evident that this apparatus will likewise be able to render services in scientific researches and laboratory operations, by sparing the operator the trouble of continually consulting his watch.--_La Lumiere Electrique_.

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[THE GARDEN.]

THE ZELKOWAS.

Two of the three species which form the subject of this article are not only highly ornamental, but also valuable timber trees. Until recently they were considered to belong to the genus Planera, which, however, consists of but a single New World species; now, they properly constitute a distinct genus, viz., Zelkova, which differs materially from the true Planer tree in the structure of the fruit, etc. Z. crenata, from the Caucasus, and Z. acuminata, from Japan, are quick growing, handsome trees, with smooth bark not unlike that of beech or hornbeam; it is only when the trees are old that the bark is cast off in rather large sized plates, as is the case with the planes. The habit of both is somewhat peculiar; in Z. crenata especially there is a decided tendency for all the main branches to be given off from one point; these, too, do not spread, as for instance do those of the elm or beech, but each forms an acute angle with the center of the tree. The trunks are more columnar than those of almost all other hardy trees. Their distinct and graceful habit renders them wonderfully well adapted for planting for effect, either singly or in groups. The flowers, like those of the elm, are produced before the leaves are developed; in color they are greenish brown, and smell like those of the elder. It does not appear that fruits have yet been ripened in England. All the Zelkowas are easily propagated by layers or by grafting on the common elm.

_Zelkcova crenata_--The Caucasian Zelkowa is a native of the country lying between the Black and the Caspian Sea between latitudes 35° and 47° of the north of Persia and Georgia. According to Loudon, it was introduced to this country in 1760, and it appears to have been planted both at Kew and Syon at about that date. A very full account of the history, etc., of the Zelkowa, from which Loudon largely quotes, was presented to the French Academy of Science by Michaux the younger, who speaks highly of the value of the tree. In this he is fully corroborated by Mirbel and Desfontaine, on whom devolved the duty of reporting on this memoir. They say that it attains a size equal to that of the largest trees of French forests, and recommend its being largely planted. They particularly mention its suitability for roadside avenues, and affirm that its leaves are never devoured by caterpillars, and that the stems are not subject, to the canker which frequently ruins the elm. The name Orme de Siberie, which is or was commonly applied to Zelkova crenata in French books and gardens, is doubly wrong, for the tree is neither an elm nor is it native of Siberia. In 1782 Michaux, the father of the author of the paper above mentioned, undertook, under the auspices, of a Monsieur (afterward Louis XVIII.), a journey into Persia, in order to make botanical researches.

"Having left Ispahan, in order to explore the province of Ghilan, he found this tree in the forests which he traversed before arriving at Recht, a town situated on the Caspian Sea. In this town he had opportunities of remarking the use made of the wood, and of judging how highly it was appreciated by the inhabitants." The first tree introduced into Europe appears to have been planted by M. Lemonnier, Professor of Botany in the Jardin des Plautes, etc., in his garden near Versailles. This garden was destroyed in 1820, and the dimensions of the tree when it was cut down were as follows: Height 70 feet, trunk 7 feet in circumference at 5 feet from the ground. The bole of the trunk was 20 feet in length and of nearly uniform thickness; and the proportion of heart-wood to sap-wood was about three quarters of its diameter. This tree was about fifty years old, but was still in a growing state and in vigorous health. The oldest tree existing in France at the time of the publication of Loudon's great work, was one in the Jardin des Plantes, which in 1831 was about 60 feet high. It was planted in 1786 (when a sucker of four years old), about the same time as the limes which form the grand avenue called the Allee de Buffon. "There is, however, a much larger Zelkowa on an estate of M. le Comte de Dijon, an enthusiastic planter of exotic trees, at Podenas, near Nerac, in the department of the Lot et Garonne. This fine tree was planted in 1789, and on the 20th of January, 1831. it measured nearly 80 feet high, and the trunk was nearly 3 feet in diameter at 3 feet from the ground." A drawing of this tree, made by the count in the autumn of that year, was lent to Loudon by Michaux, and the engraving prepared from that sketch (on a scale of 1 inch to 12 feet) is herewith reproduced. At Kew the largest tree is one near the herbarium (a larger one had to be cut down when the herbarium was enlarged some years ago, and a section of the trunk is exhibited in Museum No. 3). Its present dimensions are: height, 62 feet; circumference of stem at 1 foot from the ground, 9 feet 8 inches; ditto at ground level, 10 feet; Height of stem from ground to branches, 7 feet; diameter of head, 46 feet. The general habit of the tree is quite that as represented in the engraving of the specimen at Podenas. The measurements of the large tree at Syon House were, in 1834, according to Loudon: Height, 54 feet; circumference of of stem, 6 feet 9 inches; and diameter of head, 34 feet; the present dimensions, for which I am indebted to Mr. Woodbridge, are: Height, 76 feet; girth of trunk at 2½ feet from ground, 10 feet; spread of branches, 36 feet.

IDENTIFICATION.--Zelkova crenata, Spach in Ann. des Sc. nat. 2d ser. 15, p. 358. D. C. Prodromus, xvii., 165 Rhamnus ulmoides, Güldenst. It., p. 313. R carpinifolius, Pall. Fl Rossica, 2 p. 24, tab. 10. Ulmus polygama, L C. Richard in Mem. Acad. des Sciences de Paris, ann. 1781. Planera Richardi, Michx. Fl. bor. Amer. 2, p. 248; C.A. Meyer, Enumer. Causas. Casp., n. 354; Dunal in Bulletin Soc. cent d'Agricult. de l'Herault. ann. 1841, 299, 303, et ann. 1843, 225, 236. Loudon, Arbor, et Frut. Brit., vol. 3, p. 1409. Planera crenata, Desf. Cat. Hort. Paris et hortul, fere omnium. Michaux fil. Mem. sur le Zelkowa, 1831. Planera carpinifolia, Watson, Dend. Brit., t. 106. Koch Dendrologie, zweit theil, sweit. Abtheil. p. 425.

_Var pendula_ (the weeping Zelkowa).--This is a form of which I do not know the origin or history. It is simply a weeping variety of the common Zelkowa. I first saw it in the Isleworth Nurseries of Messrs. C. Lee & Son, and a specimen presented by them to Kew for the aboretum is now growing freely. I suspect that the Zelkova crenata var. repens of M. Lavallee's "Aboretum Segrezianum" and the Planera repens of foreign catalogues generally are identical with the variety now mentioned under the name it bears in the establishment of Messrs. Lee & Son.