Comparative Nutritive Properties of Food.-A curious report on this subject, presented to the French minister of the interior, by Messrs. Percy and Vauquelin, two members of the Institute, has been published. The result of their inquiries is as follows:-In bread, every 100lb. weight are found to contain 80lb. of nutritious matter; butcher's meat, averaging the various sorts, 35lb. in 100lb.; French beans 92lb. in 100lb.; broad beans, 89lb. in 100lb. ; peas, 93lb. in 100lb.; lentils, 94lb. in 100lb.; greens and turnips, which are the most aque ous of our vegetables used for domestic purposes, furnish only 8lb. of solid nutritious substance in 100lb.; carrots, 14lb. in 100lb.; and what is very remarkable, as being in opposition to the hitherto acknowledged theory, 100lb. of potatos only yield 25lb. of substance: 1lb. of good bread is equal to 24lb. or 3lb. of best potatos; and 75lb. bread, and 30lb. meat, is equal to 300lb. of potatos; or, to go more into detail, lb. bread and 5oz. meat are equal to 3lb. of potatos; 1lb. of potatos is equal to 4lb. of cabbage, and 3lb. of turnips; but 1lb. of rice, broad beans, or French beans, in grain, is equal to 3lbs. of potatos. It is curious, that, in a subject apparently of merely scientific inquiry, a spirit of nationality should have intruded itself; and yet we suspect that to be the case here. It will be observed, that the preference for nutritive properties is given to beans, peas, and lentils, over potatos, turnips, and carrots. The fact is, that the former vegetables are the favou

rites of the French, among whom they have been long cultivated, and the latter vegetables are of a later introduction, and, what has some influence on French taste, are of English origin. The opinion of English chemists is in favour of the English preference of roots to the vetch-tribe of vegetables. Cicero, who had paid some attention to agriculture, is on the English side of the question. It may be further observed, that the French report determines bread to be vastly superior in nutriment to animal food.

The French do not

eat much meat; but if bread is so nutritive, they ought to be the most vigorous people on the earth; for of bread, independently of other food, the Frenchman eats six times as much as an Englishman.

Considerations on the existence and state of Sulphur in Vegetables.

M. Planche suspended a piece of rag, impregnated with acetate of lead, and also a plate of clean copper, within the capital of an alembic in which he was drawing off distilled waters from plants, and found that the above re-agents were powerfully acted on, as if they had been exposed to a stream of sulphuretted hydrogen. He found, moreover, that water and sulphur boiled together, as also roll sulphur heated, without the addition of water, evolved sulphuretted hydrogen; and from the two latter experiments he infers, that in plants the sulphur is in its simple state. According to M. M. Thibierge and Robiquet, the oil of mustard contains a large quantity of sulphur; and from some com.. parative trials, it seems there to be

in the state of sulphuretted hydrogen. In fact, distilled water, saturated with the essential oil of mustard, blackens the solution of nitrate of silver. Oil of caraways absorbs a very large quantity of sulphuretted hydrogen gas, when it is passed through it; and assumes, in consequence, a very fetid odour. He supposes that the sulphur which exists as such in the mustard-seed, is converted into sulphuretted hydrogen during distillation with water, and in this state unites to the oil. A portion of the sulphur is deposited at the end of some days. The following plants yielded much sulphur; the flowers of the elder, linden, and orange-tree; the whole plant of pellitory and mercury; the flowering tops of hyssop, melilot, tarragon, and rue; the seeds of dill, caraway, cummin, and fennel; and clove-buds. Journal de Pharmacie, Aug. 1822.

British Indigo. A discovery A discovery has been recently made, which promises the most important consequences in a commercial and agricultural point of view. About two years ago, 280 acres of land, near Flint, in Wales, were planted with the common holyhock or rose mellow, with the view of converting it into hemp or flax. In the process of manufacture, it was discovered that this plant yields a bright and permanent bluc, equal to that of Indigo.

The

Trifolium Incarnatum. professor of agriculture and botany in the university of Modena strongly recommends a species of clover, that has not hitherto been cultivated in this country, namely the Trifolium Incarnatum,

or

crimson clover. He recommends this plant as the earliest of trefoils; as the most useful for increasing

forage; as requiring only one ploughing and harrowing to cover the seed; as peculiarly calculated for dry soils, even gravels; and as preferring the mountain to the plain. It is so hardy, that it may be sown even in autumn, and it stands severe frosts well. If sown in spring, it will yield a good crop the same year. Some experiments have been tried with this plant in Berwickshire, which in a great measure justify what has been urged in its favour; and, on the whole, it seems well entitled to the attention of those who are desirous of promoting British husbandry.

Management of Apple Trees.A gentleman in Essex, having in his orchard many old wornout apple trees, which produced fruit scarcely larger than a walnut, last winter took freshmade lime from the kiln, slaked it with water, and well dressed the trees with a brush. The result was, that the insects and moss were completely destroyed, the outer rind fell off, a new, smooth, clear one was formed, and the trees, although some of them twenty years old, have now a most healthy appearance.

Method of forcing Asparagus, by J. Sabine, Esq.-" The general appearance of the forced asparagus, used at table in the months of December, January, and February, is a sufficient indication of defective management in its production. When I first examined the method practised by Mr. Thomas Hogg, for forcing early potatos, it occurred to me, that the same principle might be applied to raising early asparagus, viz. that of placing the roots of the plants over a substratum not in a state of fermentation, and by introducing into the bed the warmth necessary to force

them, from hot linings to the sides; for I considered that the weak and drawn state of forced asparagus is occasioned by the action of the dung immediately on its root. My opinions, I think, are confirmed by the successful practice of Mr. W. Ross, who, in the month of January, had some of the strongest asparagus I ever noticed at that season. He sent a sample, at my request, to the general meeting of the Horticultural Society in February last. The pits, in which his succession pines are kept in the summer, have at bottom a layer of leaves, about eighteen inches deep, covered with the same thickness of tan, which becomes quite cold when the pines are removed. In one of the pits he spread over the entire surface of the old tan a quantity of asparagus roots, which he covered with six inches more of tan, and applied linings of hot dung, successively renewed, round the sides, keeping up thereby a good heat. This was done in the middle of December, and in five weeks the crop was fit for use. As soon as the shoots made their appearance, and during the day-time, he took off the lights, introducing as much air as possible, which gave them a good natural colour, and the size was nearly as large as if they had been produced in the open ground, at the usual season. I observed to Mr. Ross, that I thought the plan would be improved, if the roots were planted in mould, rather than in tan in this point he agreed with me, observing, that he would nevertheless retain the underlayer of eighteen inches of tan, which, he was convinced, would be of great service, since it so readily admitted the passage of the heat; and that he should, in all cases, prefer VOL. LXIV.

the use of a bed so constructed, to the cold dung-bed of Mr. Hogg, on which he had grown the early potatos, which, from having lain together for some time, became too compact for the heat to penetrate into them easily.

Directions for preserving the Buds of Fruit-trees for Conveyance. -Mr. Knight in the Trans. Hortic. Society states, that, in conjunction with sir C. Monck, he made some experiments to discover the most eligible mode of transferring buds from one part of the kingdom to another, the result of which was satisfactory. "It has led me," says Mr. K. " to adopt a better mode of using buds which have become somewhat withered, than I previously knew. Several different methods of packing buds were tried; but the following, which was first adopted by sir Charles Monck, having proved to be at once the most efficient and most easy of execution, it is useless to describe any other. The leafstalks of the buds were reduced to a very short length, and the young branch was then inclosed in a double fold of cabbage-leaf, bound close together at each end and inclosed in a letter. It was found advantageous to place the lower surface of the cabbage-leaf inwards, by which the inclosed branch was supplied with humidity, that being the perspirating surface of the leaf, and the other surface being nearly, or wholly, impervious to moisture. I did not usually receive the buds from Belsay-castle, the seat of sir Charles Monck, in Northumberland, in less than five or six days, and the leaf-stalk had then often parted from the buds, and the bark could not very readily be detached from the wood. The latter substance was therefore suffered to 2 Y

remain; but it was pared very thin, particularly such part of it as extended above the bud; and, as the loss of the leaf-stalk deprived me of the usual method of holding the bud, I found it necessary to suffer that to remain attached to the branch above it, or to a part of it, till I had placed the bud in its proper position; it was then severed from the branch with a sharp knife, and the bud almost always succeed ed, as well as one recently taken from the tree would have done."

Botany of South America.-M. Bompland, the friend and companion of Humboldt in his peregrinations in South America, after the late changes in France, passed over to Buenos Ayres, and settling there, has devoted himself entirely to scientific pursuits. He has established a garden of plants, and for several months has been engaged in a botanical excursion in Paraguay, a country abounding in all kinds of vegetable and mineral curiosities. The following is the extract of a letter written by him from Corrientes.

"The whole of the country called here the Missions, exceeds description, and in it, at every step, one meets with things both new and useful to natural history. I have already collected two thousand plants, a large quantity of seeds, a number of stones, besides making most useful observations, such as will greatly promote a geological knowledge of this part of America. I have also collected insects, birds, &c. Among the number of interesting plants to which my attention has been called, I am of opinion that the country may hereafter derive great advantages from the three new kinds of indigo I have found in these fertile regions. They are

very different from the plant from which indigo is obtained in Caraccas, Brazil, Mexico, and India. I flatter myself that the South Americans will avail themselves of this discovery, and cultivate and improve a plant that has hitherto been disregarded under the common name of Yuyo. It is well known that the indigo of Venezuela, which formerly was superior to that of Guatemala, in consequence of the improvements in extracting it, and which competes with that of India in price, in England is worth from 13 to 20 rials per pound. In Venezuela as much as 3 or 400,000 dollars of indigo were annually obtained, and there the pound has frequently been bought at seven rials. The superior quality that may be obtained from this newly-discovered plant, and the facilities of conveyance down to a shipping port, render it an object of great importance to a country that has only few exports, and its cultivation, if encouraged by the government and undertaken by capitalists, will, in a few years, furnish an interesting and staple commodity to trade."

From the known zeal and researches of this experienced botanist, the scientific world has much to expect, and the new government by whom he is now employed will derive considerable advantages from his turning his attention, not only to objects of mere curiosity, but also to such as will eventually improve the trade and resources of the country. There are many other articles, to which the attention of the Buenos Ayres government ought to be called. The Seda Silvestre, or a species of wild silk, left in the woods by a certain caterpillar, is found on the banks of the Parana,

and would constitute a valuable export. Very good cochineal may also be gathered in Tucuman, besides a great quantity of beeswax. The Rubia Tinctoria is found in many of the extended forests, but the best is in Tarija, Chaco, and the Sierra of Cordova; it yields a brilliant colour. It

was not till within very few years, that notice was taken of a new mode of dying green, from a production called by the Spaniards Clavillo, or little nail, from its resembling one. Some persons assert it to be the excrementitious deposit of a certain insect smaller than the cochineal, and others that it is the insect itself. Hitherto it has only been gathered in Carquejia, and the point is found introduced into the bark of a shrub. It was first used by the poor of the country, and it has since been proved by repeated experiments, that the Vicuñia and Alpaca wools, as well as cotton, after being prepared by astringents, such as alum, and previously boiled in a yellow dye, when thrown into a solution of Clavillo, acquire a beautiful green

colour. The shade of this simple is in itself greenish, and by being kept, it darkens considerably. Abundance of it is found in the valley of Catamarca and province of Tucuman, but no scientific experiments have been made with it.

A

Natural verdigris, of a metallic substance, is found in the copper mines of the districts of Carangas, Pacages, Lipes, and Atacama, as well as Oruro, and is used instead of artificial verdigris for paint and colouring pottery. It easily dissolves in mineral acids, and all the earth or heterogeneous particles precipitate to the bottom. species of metallic combination, of arsenic mineralized by sulphur, called Oro Pimente, is also collected in various parts of the Cordillera of the coast, particularly at a place called Perinocota, 25 leagues from the town of Carangas. It is found to be an excellent article to fix colours. In short, numerous plants, gums, resins, minerals, &c. will, in the course of time, be brought over from every part of South America.

Application of Machinery to the Calculating and Printing of Mathematical Tables.-Charles Babbage, esq. F.R. S. London and Edinburgh, &c. in a letter addressed to sir Humphry Davy, president of the Royal Society of London, has announced to the world, that he has invented various machines, by which some of the more complicated processes of arithmetical calculation may be

performed with certainty and dispatch. Mathematicians are well aware that tables of every kind may now be constructed by the aid of one of the finest inventions of modern analysis, the theory of finite differences. It is in this way that Mr. Babbage proposes to apply his machines to the purpose of calculation. He states that his first engine is capable of computing any table by the aid