Showing an increase of 40 per cent. over the old rule of correction.

From experiments with different burners and with gas from rich coals, Prof. Silliman says:

"A comparison of the results will show that the coincidences with the requirements of the theorem of Farmer are, within the limits assigned, too numerous, and too closely accordant, to be considered as otherwise than pointing clearly to its general truth. A rigorous demonstration cannot be expected, as there are too many variable functions of unknown value involved in the best methods at present known for photometric measurements, to permit more than an approximate proof of its general accuracy. Every photometric observer must recognize its importance, and the necessity in his observations of bringing the consumptions of gas and sperm to the agreed standard.

"To the consumer of gas the evident inference from the data here presented is that where it is important to obtain a maximum of economical effect from the consumption of a given volume of illuminating gas, this result is best obtained by the use of burners of ample flow.

"Where a moderate light of equal diffusion is required over a large space, as in public rooms, it may be expedient to use numerous small jets; but when the maximum intensity obtainable from a given volume of illuminating gas is desired, intensity of burners of large consumption is plainly indicated."- Abstract from a paper read by Prof. Silliman at the Salem meeting of the Am. Association, Aug., 1869.

GAS FROM WOOD.

The following fact may be mentioned in connection with the manufacture of gas from wood. In those countries where this material is abundant, and coal not accessible, wood, aided by the addition of some substance furnishing a rich hydro-carbon, may be made to furnish a very useful illuminating gas, and an economical one, especially when the residue in the retorts and material distilled with the gas can be rendered serviceable. In Coburg, Canada, it is said to have been used advantageously, furnishing a good gas and a valuable residue, namely: —

Two parts pine wood.

One part hard wood.

One part bones.

The residue in the retorts is an excellent charcoal for bleaching purposes, and the other residues are quite serviceable. Where bones cannot be obtained, offal and other coarse animal matter can be used to mix with the wood. This suggestion is worthy of consideration, especially for many small towns peculiarly situated.

9

LITTLE-KNOWN FIBROUS PLANTS.

There has been of late a considerable search after plants producing fibres that could be advantageously used in the arts of paper-making, rope-making, and the manufacture of textile fabrics. Some of these materials have been discovered in North and South America; but a large majority of those claiming the attention of manufacturers are found in Southern Asia, more particularly in India.

Among these stands most prominently a plant of the nettle family, called by the natives "Tchuma," the botanical name of which is Urtica nivea. In Assam, both a cultivated and a wild variety are found, and in the Malayan peninsula, Panang, and Singapore, another variety grows wild, the fibre of which is unusually strong. This has a Malay name, Ramee," and is in botany known as the Urtica tenacissima. · This plant is identical with the ramie, now cultivated in the Southern States, brought originally, we believe, from Java.

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Mr. Leonard Wray, in a paper read before the Society of Arts, in London, describes the beautiful fibre of the "Rheea as being worth in England two shillings and four pence per lb., and says, "the fabrics made from it are of so strong and so lustrous a character as to be in universal demand. Pity, indeed, is it that this splendid fibre can be obtained only in such small quantities! No other supplies can be looked for, except from China, nor can we expect much from that country either. Its growth and preparation have been tried by most intelligent Englishmen in India; but they found, first, that the separation of the fibres from the plants was a most difficult and laborious operation; and, secondly, that the yield per acre, per annum, was exceedingly small. Indeed it is said to yield only one to one and a half hundred weight of fibre to the acre, —a fact which forbids any European from entertaining hope of cultivating it at a profit, which is much to be regretted."

Mr. Wray also believes the plants called Pederia fœtida, the "Tettee," 99 66 Moorva," and the pine-apple, each and all of them, hold out the promise of amply remunerating any European who will attempt in a judicious manner to utilize the beautiful fibres they contain. Their fibres are fine, silken, and strong. He says, "The Pederia foetida certainly has the most silky and lustrous fibre any one can desire, and its being only in lengths from joint to joint seems the sole objection to it. Still, these joints are often 12 inches apart, while the finest Sea-Island cotton is not more than one inch to an inch and a half in staple. Attention ought, therefore, to be directed to this lustrous fibre-yielding plant.

"The Jettee, again, is jointed, but the joints are sometimes two feet apart, and the fibre proportionably long. It is a most excellent fibre, and will be sure to make its way.

"The pine-apple, with its beautiful fibre, exists in thousands of acres in the Straits of Malacca, and may be had at Singapore

in any quantity for the trouble of gathering, yet no one seems to regard it."

Another important fibre-producing plant is the Bromelia penguin, from which the surprisingly beautiful Manilla handkerchiefs are made, as well as the celebrated "Pigna" cloth, an Indian fabric commanding always an extreme fancy price. This is a kind of wild pine-apple said to be exceedingly abundant.

The late Mr. Temple, formerly Chief Justice of British Honduras, some years since exhibited a quantity of this fibre to the Society of Arts, calling it silk grass.

Mr. Wray says we may search the world through and not find another plant capable of yielding so rich, so abundant a supply of a fibre which in quality cannot be excelled, and that it is a plant which we may look to, to provide us with a large amount of the very best quality of fibre.

The fibre alluded to can be grown exceedingly cheap, and it is asserted that the manufacture involves no difficulty. The fibre is said to be separated by a machine constructed somewhat on the principle of the threshing machine, the plant being passed at a slow rate along a platform having a yielding surface, through rollers and beaters; and, when this is done with the plant in a green state, it comes out at the other end of the machine very good fibre, which is improved by repeating the operation. A stream of water is used to wash the pulp away as it is expressed from the fibre.

Among cordage fibres there is the nettle and the canna; the latter often growing 14 feet high. The whole stalk and leaf are said to be one mass of fibre; and the root furnishes a species of arrow-root said to be the most nutritious of all the starches.

It is thought that some if not all of these plants can be grown in Europe, and if so they ought to thrive in parts of the United States. It is not a just inference that because a plant is a native of a tropical clime it will not thrive in temperate climates. Though this may be the rule, there are numerous exceptions. Our Commissioner of Agriculture would do the country a service by obtaining and distributing the seeds of these plants in sections most favorable to their growth, if he has not already done so. We are far from believing the vegetable kingdom contributes to the wealth of mankind all, or nearly all, it is capable of doing. It is within the memory of yet young men, that the tomato was considered a useless vegetable; yet to-day there is probably no fruit grown in this country-if we except the apple. more generally used and esteemed. It is quite probable that many plants indigenous to our soil possess fibre which would be of great service, if properly worked. Among those which seem most promising are some of the “ Asclepias" family, popularly known as "milkweeds," 99 66 silkweeds," and so forth. The plants are large, rapid and thrifty growers, and their pods contain a large amount of cotton-like fibre, which, though it might not be sufficiently strong for textile fabrics, would make, we think, excellent paper stock.

THE IXTLE FIBRE.

The following is a letter from Hon. J. McLeod Murphy to the Commissioner of Agriculture, accompanied with 3 skeins of the ixtle fibre, Bromelia sylvestris, each produced from a single leaf, of which a single plant might average 20. We extract the substance of this letter from the "Report of Department of Agriculture" for May and June.

"First of all, before I describe the plant and the method of its cultivation, I beg to call your attention to the extraordinary length and strength of the individual fibres, their susceptibility of being divided almost infinitesimally without breaking, their flexibility without kinking, and the readiness with which they receive and hold vegetable or chemical dyes without being impaired. Since my return from Mexico, I have had little or no opportunity of testing this plant practically; but some samples, such as I send you, were given to an old and experienced maker of fishing-tackle, and he does not hesitate to pronounce the ixtle fibre as superior, in every respect, for the manufacture of trout and other fishing lines, not only, on account of the readiness with which it can be spun, its extraordinary strength, but its perfect freedom from kinks when wet. The only secret, if there is one, consists in the preliminary precaution of boiling the fibre (as you have it here) before twisting it. In this one respect it will super

sede the use of silk.

"Apart, however, from its use as a thread, I hazard nothing in saying that it forms the best paper stock that can be obtained. I speak now in reference to the imperfect, withered, rejected, and dried leaves, from which the fibre cannot be conveniently extracted by the indifferent mechanical means that the Indians employ. Although I have no samples of paper made from this source just now at hand, yet I can assure the department that several magnificent samples of paper for banking and commercial purposes have been made by manufacturers in the Eastern States, from the dried leaves of the ixtle plant, brought from the neighborhood of Tabasco.

"The samples of fibre I send with this were obtained by the most primitive means, namely, by beating, and at the same time scraping, the leaf of the plant (in a green state) with a dull machete. Then, after the removal of the glutinous vegetable matter, it is combed out and rubbed between the knuckles of the hand until the fibres are separated. The next step is to wash it in tepid water and bleach the skeins on the grass. This is the method pursued by the Indians on the Isthmus of Tehuantepec; and the average product for the labor of a man is from 4 to 5 pounds per day.

"It is scarcely necessary to tell one so well informed as yourself that this spontaneous product is the Bromelia sylvestris, which differs, in some respects, from the Agave Americana, the pulque de maguey, and Agave sisalana, of Campeche; a difference arising solely from soil and climate influences. The name ixtle is given to that species which is characterized by the production

of the long fibre; and chiefly because the leaf, being shaped like a sword, has its edges armed with prickles, similar, in fact, to the weapon formed from itzli, or obsidian, used by the Aztecs. Hence the term. The pita, on the other hand, although obtained from a variety of the same plant, is a coarser and shorter fibre, which grows in the tierras templadas. The name comes from the word pittes, which is given to the plantations of the pulque plant in the uplands of Mexico. But the peculiarity of the ixtle is, that it grows almost exclusively on the southern shore of the Mexican gulf, or in what is known as the 'sota vento,' that is to say, between Alvarado and Tabasco, and extending as far inland as the northern slopes of the dividing ridge which separates the Atlantic from the Pacific. The points generally selected for its cultivation are the edges of a thick forest, from which the small undergrowth is removed by cutting and burning. The roots of the plants are then set out at a distance of 5 or 6 feet apart; and at the end of a year the leaves are cut and scraped.' The chief object is to obtain a constant shelter from the rays of the sun, which would otherwise absorb the moisture, and so gum the fibres together as to make them inseparable.

"The average length of the leaf is 6 feet, and the time to cut it is clearly indicated by the upward inclination it makes. In other words, the radical leaves cease to form curved lines with their points downward, but stiffen themselves out at an angle, as if to guard the source of efflorescence. When the ixtle is young its fibres are fine and white, but as it grows in age they become longer and coarser; and in a wild state the thorns are very numerous, but by cultivation they are diminished both in size and number, and in many instances there are none at all. Where any quantity of leaves require to be handled, a pitchfork would be very useful, especially if gathered for paper stock. A few days after cutting, the sun would dry them out, the thorns would drop off, and then they could be easily baled. Independent of the great value which the ixtle has for textile fabrics, and for paper, it possesses many valuable medicinal properties, to which I need not allude. It requires no labor to cultivate it, and no insect is known to feed upon it. It grows everywhere in the primeval forests of the Gulf coasts, and, in my opinion, is far superior to any of the textile fabrics. But as yet no mechanic has succeeded in devising a means of effectually extracting the fibre, and until this is done I presume that its real commercial value will remain unappreciated.

"You will readily discover the superiority of the ixtle over the jenequin of Cuba, or the hemp which comes from Sisal and Campeche."

SIGNALLING ON BOARD THE CABLE FLEET.

The London" Gazette" gives the following interesting description of the manner of signalling through the cable on board the Great Eastern :