deem further description superfluous. Early in June the insects give to the trees the appearance of being covered with hoar frost, being "changed into wax;" soon after this they are scraped off, being previously sprinkled with water. If gathering be deferred till August, they adhere too firmly to be easily removed. Those which are suffered to remain to stock trees the ensuing season secrete a purplish envelope about the end of August, which at first is no larger than a grain of rice; but as incubation proceeds, it expands and becomes as large as a fowl's head, which is in spring, when the nests are transferred to other trees, one or more to each, according to their size and vigor, in the manner already described.

On being scraped from the trees, the crude material is freed from its impurities-probably the skeleton of the insect-by spreading it on a strainer, covering a cylindrical vessel, which is placed in a caldron of boiling water. The wax is received into the former vessel, and on congealing is ready for market.

The pe-la, or white wax, in its chemical properties, is analogous to purified beeswax, and also spermaceti, but differing from both; being, in my opinion, an article perfectly SUI GENERIS. It is perfectly white, translucent, shining, not unctuous to the touch, inodorous, insipid, crumbles into a dry inadhesive powder between the teeth, with a fibrous texture resembling fibrous feldspar; melts at 100° Fah.; insoluble in water; dissolves in essential oil; and is scarcely affected by boiling alcohol, the acids, or alkalies.

The aid of analytical chemistry is needed for the proper elucidation of this most beautiful material.* There can be no doubt that it would prove altogether superior in the arts to purified beeswax. On extraordinary occasions, the Chinese employ it for candles and tapers. It has been supposed to be identical with the white wax of Madras; but as the Indian article has been found useless in the manufacture of candles, (Dr. Pearson, Philosophical Transactions, vol. 21,) it cannot be the same. It far excels also the vegetable wax of the United States, (Myrica cerifera.)

Is this substance a secretion? There are Chinese who regard it as such; some representing it to be the saliva, and others the excrement, of the insect. European writers take nearly the same view; but the best authorities expressly say that this opinion is incorrect, and that the animal is changed into wax. I am inclined to believe the insect undergoes what may be styled aceraceous degeneration; its whole body being permeated by the peculiar product in the same manner as the coccus cacti is by carmine.

It costs at Ningpo from 22 to 35 cents per pound. The annual product of this humble creature in China cannot be far from 400,000 pounds, worth more than 100,000 Spanish dollars.

NINGPO, August, 1850.

* Some interesting particulars on this subject are contained in a Memoir in the Philosophical Transactions for 1848, by Mr. B. C. Brodie, entitled, "On the Chemical Nature of a Wax from China." Mr. Brodie states that, although in appearance the substance resembles atearine or spermaceti more than beeswax, it comes nearest to purified cerin! The Comptes Rendus for 1840, tome x, p. 618, contains a communication by M. Stanislas Julien on the China wax, and the insect which yields it. The wax insects are there stated to be raised from three species of plants: these are Niu-tching, (Rhus succedanea,)_ Tong-tsing, (Ligustrum glabra,) and the Choui-kin, supposed to be a species of Hibiscus. "Rhus succedanea, or a nearly allied species, occurs in the Himalayah.

CULTURE AND PREPARATION OF SUMACH.

PALERMO, May 30, 1850. DEAR SIR: In reply to your letter of yesterday's date, on the subject of the mode of cultivation of sumach in Sicily, I beg to submit the following remarks:

Sumach is an article of commerce of great importance to the Sicilians, as it is also with the Americans. And it is my opinion that this article, so valuable for manufacturing purposes, for tanning, &c., can be produced in the United States in sufficient quantity to supply the world, if the mode of its culture be understood and proper attention be paid to it. I have no doubt that it is the same kind that grows in the United States, which there runs to the size of trees. In Sicily they plant the roots or small plants from two to three feet apart, not always in regular rows, as we do Indian corn; hills about three feet apart, rows about four, so that the plough or harrow can save the hand labor of the hoe. They hoe it two or three times before the rains finish in May, and gather it in July and August. The leaves are the only parts made use of. After being separated from the twigs by threshing, (or in this country both ways-by threshing and by treading off with oxen or horses,) the leaves are then ground to the state of fineness in which you see it in the United States, being passed through sieves or bolting-cloths of sufficient fineness, and put into bags of one hundred and sixty pounds each.

The proper season for planting the roots or plants is in November, December, and January. When the season is rainy, the plants take root better. The root or stump is cut off from four to six inches above ground. The scions or sprouts spring up four to six out of each root; and when at maturity, which in this island is in July or August, they are all cut off at the stump, and laid in small handfuls (not spread out much, as the sun will turn the leaves yellow) to dry-say for a day or so great care being taken that no rain falls on them. Perhaps in this country it may answer to plant nearer together than would be advisable in America, on account of the greater heat of the sun here, and thus shade the ground better.

The leaves are ground in mills mostly by horse-power; but water or steam power would be much cheaper and better. The perpendicular running stones weigh nearly three thousand pounds; they run double or single round an upright shaft. The nether or foundation stone is heavier and one-third greater in diameter than the running stones. The grinding surface of these latter is slightly rough, being occasionally touched with the pick or cold chisel. Hard granite stones answer; here they use a volcanic stone, which is as hard as marble. There follows round the running stones a little piece of wood, that keeps the leaves always under the stones. When ground fine enough, it is sifted or bolted in a large tight room, with a door to enter and fill the bags. In Sicily the article is more or less adulterated with spurious stuff, such as other kinds of leaves, and an article called brucca, which resembles the juniper bush in New England; this has no value in itself.

I believe the first year they do not cut off the sprouts. In the second and following years a curious freak of nature produces a single plant a foot or so distant from the original root; and this little plant it is which

they usually make use of to transplant. Now the plough or harrow would prevent these from growing, as they would be in the track; and this may be the reason why they hoe it. Still I think the plough or harrow must be used in our country, and some way or other contrived to save these little plants, if wanted. I would recommend you to let me engage to begin with this mode of cultivating sumach. Let one or two young Sicilian farmers be hired to go to Virginia for two or three years, who understand the cultivation not only of sumach, but also of lemons, oranges, grapes, and olives, as well as other productions of Sicily. Their wages in Sicily are from twenty-five to thirty-three cents per day, and find themselves; it should perhaps be half a dollar a day in the United States. Their passage to the United States would be about $25, of a little over; or perhaps our Government would deem it of importance enough to give them a passage either in a merchant or a United States vessel. They should take with them all kinds of Sicilian wheat and other grains, and sumach plants. I can always obtain in the proper season-say December and January-20,000 if required; cost, a trifle. If the lemon and orange trees of this place were introduced-say into Florida, they would stand the cold much better than those already introduced from Cuba, which are not of a hardy kind. I can obtain all that may be wanted for an introduction, and Sicilians to cultivate the trees. The exports of sumach to the United States last year were 65,000 bags. Lemons and oranges, 350,000 boxes from Sicily; more than three-fourths from this port. Such is the trade in these articles alone, besides large quantities of other productions. If I can serve you or my country in any way beneficially, it will give me great pleasure to do so.

I am, dear sir, your obedient servant,

W. D. PORTER, Esq.,

U. S. N., Washington.

JOHN M. MARSTON.

The soil of Sicily generally is a limestone formation-a reddish soil, which I think corresponds with the land in Maryland, Virginia, North and South Carolina, and the States west of those named. In Sicily, sumach is cultivated in the valleys or level grounds, or on the sides of the mountains; it requires no rain for two months before harvesting it. The soil of Sicily is so fertile that I do not think they manure the ground at all for sumach.

We suppose that the reason of the superiority of Sicilian sumach over that of other countries lies in the mode of cultivating it. All the leaves are the productions of the young sprouts that spring up from the stump every year. Being so young, the leaves are full of life when cut, and have not decayed, like those of old trees. This, with a dry climate in the latter part of the season, and the soil suiting the plant, gives it the reputation it has all over Europe and America.

J M. M.

III.

CATTLE BREEDING.

ON THE PHILOSOPHY OF FATTENING CATTLE.

[From the London Plough.]

Next to understanding properly the chemical analysis of soils, the application of proper manures, and the crops which should be grown from the land by proper tillage, there are but few subjects more deserving the attention of the practical agriculturist than a knowledge of the proper connexion which exists and should be duly preserved between the members of the animal and vegetable kingdoms. As I observed in my lectures on the "Philosophy of Agriculture," so may I now repeat man is an omniverous animal-he is so destined by the Almighty, who has so created his masticatory and digestive organs that he can live and flourish under a compound diet of animal and vegetable food; we are also told by Divine authority that "man shall not live upon bread alone;" consequently, as it is necessary that he should have recourse to substances of a different nature to use in combination, so is it equally of paramount importance that he should direct his care, skill, knowledge, and attention to the management of cattle, so that they should be able to afford him the greatest possible amount of nutritious food, and at the least possible expense in money to himself, and waste or loss, or both, in the preparation of the same.

It is my intention in the present lecture to make a few observations on this subject, to show you the wisdom that experience has taught us, and which I have drawn from many sources-the results of the labors of practical men. To some I may have the pleasure of addressing, the theme I shall discuss may appear novel; while I doubt not that many who are here present will be able to confirm many of the truths which I shall utter.

The existing link between animals and vegetables forms one of the most beautiful chains in nature, and one which cannot be dissolved; it is one of the greatest value to the practical farmer, because it so materially affects his operations in breeding, rearing, and feeding his cattle.

In considering this subject philosophically, we must first of all examine what are the substances which enter into the office of nutrition, and ascertain by what means, as far as our limited knowledge extends, nourishment is afforded to the animal. The vegetables upon which not only cattle but ourselves are fed, consist of two portions, viz: an organic and an inorganic; and upon instituting a chemical analysis, we find that the inorganic is chiefly composed of a considerable quanity of water, much carbonic acid in combination with the salts of am

monia, and nitric acid; the inorganic portion is entirely derived from the soil from which they grow, and the science of chemistry informs us that it consists almost entirely of saline constituents and earthy particles, which, upon incineration or burning, constitute the ashes of the plants. I refer you to what I stated in my lecture on the "Philosophy of Agriculture," as to the manner in which these particles are absorbed by the plants, and which you will find published in Nos. 1 and 2 of "The Plough," detailed at length; but I may here briefly remark, that these substances are taken into the texture of the vegetable by means of the leaves and roots, which, under the chemical action and influence of the light from the sun, are decomposed-the oxygen becoming returned to the atmosphere which originally gave it; while the elements of water, with the carbon, unite to form starch, sugar, gum, or woody fibre, and, with the elements of ammonia or nitric acid, constitute albumen, casein, or gluten. Thus the plant derives its food almost entirely from the inorganic kingdom; while the animal, on the contrary, from its anatomical conformation, can only exist upon organic matter. During the present century such great discoveries have been made in the science of organic chemistry, particularly by the discoveries of the late Sir Humphrey Davy, Dr. Edward Turner, Professor Brande, Drs. Faraday and Gregory, and last, though not the least, those of Baron Justus Liebig, of Giessen--to whom may be added the labors of a rising young chemist, Dr. Lyon Playfair-that much valuable knowledge has been imparted to the philosophical and agricultural world upon the physiology of animal life, and the manner by which the system is nourished and supported.

We now, therefore, can well comprehend why one species of diet is. found to possess a greater quantity of nourishment than another-why the inhabitant of the frozen regions of the north, as I have seen in the persons of the Esquimaux and Greenlanders, should require great quantities of train-oil with his daily food. And why? His stomach will digest the rancid flesh and blubber from their rancid whales and seals; while the same species would not only be disgusting to us, but actually prove both physically and mentally injurious to the inhabitants of more congenial and warmer climates. We also understand from the same source how it is that we cannot feed animals or exist ourselves upon a diet wholly composed of sugar, starch, gum, or gelatine; and, although we cannot live upon any one of these substances, yet, when they are all properly combined, strange as it may appear to some, it is of all these materials, when properly united, that our daily food is composed. The great office of chemistry, as applied to this department of human knowledge, is to point out the peculiar wants of animal bodies, and how these are duly supplied in the food we and they daily consume. Anatomy informs us that, like the vegetable, an animal body is composed of two portions: the organic particles form a considerable portion of the flesh or softer tissues of the body; and also an inorganic portion, which Professor Berzelius, of Stockholm, Guy Lussac, Vauquelin, Thenard, and Fourcroy, with Dr. Magendie, of Paris, and other experimental chemists, have demonstrated also to constitute a small portion of the softer parts; but it is in the bones, which constitute the skeleton, that they are principally found; and these are directly derived in the herbivora (or vegetable-feeding animals) from the vegetable diet upon which they subsist,