Vickipedia

PACKFO’NG, or PETO’NG, a Chinese alloy or white metal, consisting of arsenic and copper. It is formed by putting two parts of arsenic in a crucible with five parts of copper turnings, or finely divided copper; the arsenic and copper require to be placed in alternate layers, and the whole is covered with a layer of common salt, and pressed down. When melted, the alloy contains nearly the whole of the arsenic, and is yellowish-white in color when in the rough state, but takes a flue white polish resembling silver. It is not very ductile, and cannot be fused without decomposition, as the arsenic is easily dissipated. It was formerly much used in this country, as well as China and India, for making the pans of small scales, dial-plates, and a variety of other articles requiring nicety of make, such as graduated scales for philosophical instruments. It is probably never imported now, the nickel alloys of Europe having quite superseded its use; in China, however, it is still extensively employed.

ROTATION OF CROPS. The plants like the animals of the farm differ much in their habits, and in the different sorts of food on which they subsist. The broad-leafed clovers, turnips, and mangold abstract from the air a large proportion of the materials of their growth; whilst the narrower-leafed grains and grasses, especially if their seeds are ripened, partake more largely of mineral food withdrawn from the soil. The cereals require for their healthy nutrition large supplies of phosphoric acid and silica; leguminous plants devour a large share of lime; turnips, carrots, and clover take up a great amount of potash. Corn-crops, occupying the ground during the greater part of the year, favor the growth of weeds; well-tended root-crops, on the other hand, afford better opportunity for deep culture, for the extirpation of weeds, for the convenient application of manures; whilst, being in great part consumed on the land, they raise its fertility. Mainly’ from such considerations, the farmer of arable land is led to grow a succession of dissimilar plants, or, in other words, to adopt a rotation of crops. The cereals exhausting the farm, en account of their ripened seeds being sold off. are generally alternated with fallow, root, or cleansing crops, or with beans and peas, which occupy a kind of intermediate position between the cereals and the roots; whilst clovers or grasses are taken at intervals of six or eight years. The rotation most suitable for a particular farm is, however, greatly modified by various circumstances, and especially by the nature of the soil, climate, markets, available supplies of extra manures, amount of live-stock kept, £c. That course of cropping is evidently the most desirable which will economically secure, with thorough cleanness of the soil, a high and increasing state of fertility.

Many rotations are based upon the Norfolk or four-course system, which consists of (1) Clover or mixed grass seeds; (3) Wheat, or in many parts of Scotland, oats; (3) Turnips, Swedes, mangold, potatoes, or bare fallow; (4) Barley. The details of this system are generally as follows. The clovers or grasses are mown or grazed; when cut, they are either used green or are dried for hay; the second crop is carted home for the cattle or horses; near towns, it is sold off; or it is consumed on the ground in racks by sheep, which on most highly cultivated farms receive besides a daily allowance of cake or corn. In districts where town-manure can be obtained, a top dressing is applied as soon as the first crop of grass is cut. On the poor and worse cultivated soils, the grass-crop occasionally remains down for two, or even three years, thus extending a four into a five or six years’ rotation. The clovers or mixed seeds are ploughed up in autumn, and followed generally in England by wheat, and in Scotland by oats. These crops are now usually drilled, to admit of horse and hand hoeing. After harvest, the stubble is, if possible, cleaned by the scarifier, grubber, or plough and harrows; or, where the management for several years has been good, any patches of couch-grass or other weeds are best forked out by hand. The land, especially if heavy, or intended for mangold drilled on the flat, as practised in the drier parts of England, may then be manured and deeply ploughed : the grubber and harrows, in April or May, suffice to prepare for the drilling of mangold or Swedes. Heavy land, intended either for roots or barley, should, in spring, be ploughed or disturbed as little as possible. In Scotland, and the cooler moist climates of the north and west of England, turnips and potatoes are grown on raised drills or balks, in which the manure lies immediately underneath the plant.

Frequent horse and hand hoeing should insure the thorough cleaning of the crop. Unless in the neighborhood of towns, where it is greatly more profitable to sell off the whole of the root-crop, part of the Swedes or mangold is taken home for the cattle, but the largest portion is consumed by sheep in the field. After the fallow or cleaning crop, another cereal crop is grown : under the Norfolk system, this is generally barley, with which the clovers or seeds are sown out. Where sewage or tank water is available, Italian rye-grass is often used, and on land in high condition, early large and repeated cuttings are obtained; but rye-grass has the disadvantage of being a worse preparation than clover for the wheat-crop which usually follows. The chief failing of the four-course system consists in the frequent recurrence of clover, which cannot be successfully grown oftener than once in six or eight years. To obviate this difficulty, one-half of the clover quarter is now often put under beans, peas, or vetches, thus keeping the grass or clover seeds eight years apart.

The Norfolk four-course system is unsuitable for heavy land, where a large breadth of roots cannot be profitably grown, and where their place, as a cleaning crop, is taken by bare fallow, vetches, or pulse. Bare fallows are, however, less frequent than formerly, being now confined to the most refactory of clays, or to subjects that are so hopelessly full of weeds as to require for their extirpation several weeks of summer weather, and the repeated use of the steam or horse ploughs, the scarifier, grubber, and harrows. In such circumstances, winter vetches are often put in during September or October, are eaten off by sheep and horses in June or July, and the land afterwards cleaned: this practice is extensively pursued on the heavier lands in the mid-land and southern counties of England.

In such localities, the following system is approved of—(1) The clover leas are seeded with (2) wheat; then come (3) beans, pulse, or vetches, manured, horse or hand hoed; (4) On good land, wheat succeeds; (5) Oats or barley often follow, but, to prevent undue exhaustion of plant-food, this system requires considerable outlay in artificial manures, cake, and corn; (6) A fallow, or fallow crop, deeply and thoroughly cultivated, and well manured, comes to restore cleanness and fertility; (7) Barley or wheat is drilled, and amongst this, the clover-seeds are sown. On the heavier carse-lands in Scotland, the following plan of cropping is generally practiced—(1) Clover; (2) Oats; (3) Beans; (4) Wheat; (o) Bare fallow or fallow crop, usually including a considerable breadth of potatoes; (6) Wheat; (7) Barley, with which the clovers or mixed grasses are sown. Under this system, it is difficult, with so few cleaning crops, to keep the land clean; roots, besides, are not produced in quantities sufficient properly to supply either cattle or sheep during the winter. To remedy these defects, roots may be introduced after the oats, and would be followed either by wheat or barley. This extends the rotation from seven to nine years.

In all well-cultivated districts, whether of heavy or light land, stock-farming is extending, and a more vigorous effort, is being made to raise the fertility of the land. Root-crops are accordingly more largely grown; indeed, it is sometimes found profitable to grow two root-crops consecutively; thus, after turnips, Swedes, cabbage, or mangold, well manured from the town or farmyard, and eaten off by sheep, potatoes of superior quality are produced with one ploughing, and a dose of portable manure. Specialities of management occur in almost every locality. In Essex, winter-beans follow wheat, are got off in August, and are succeeded by common turnips. Near London, and in other southern districts, early potatoes or peas are grown for market, and are immediately followed by turnips. In ninny parts of England, where the soil and climate are good, rye or vetches sown in autumn are consumed in early summer, and a root-crop then put in.

Good rotations do not necessarily insure good farming; they are merely means to an end. By carefully removing weeds, by deeply stirring the soil, and by applying appropriate manures, wheat may be grown on the same soil for an indefinite number of years. At Lois-Weedon, in Northamptonshire, the Rev. S. Smith has for twenty years cultivated alternate three-foot strips of wheat and well-forked bare fallow; the land that is wheat this year being fallowed next. Although no manure whatever is applied, and only one-half of the experimental plot is each year under crop, the yield continues to stand at four quarters per acre, which is about four bushels per acre in excess of the average acreable produce of Great Britain.

The Lois-Weedon system, owing to the outlay which it entails for manual labor, probably could not be carried out with profit on a large scale. It demonstrates, however, the inherent resources lying dormant, especially in clay-soils, and indicates how they may be rendered available by thorough cultivation. It is mainly by such cultivation that steam-power proves so serviceable in our fields. The soil is turned up deeply to the disintegrating solvent influences of wind and weather; the necessary operations are rapidly overtaken in good season; much work is accomplished in autumn; treading and poaching of the surface is avoided; whilst a larger breadth of roots is attainable for the healthy and economical support of the sheep and cattle-stock, which not only directly enhance the returns of the farm, but also raise rapidly its manurial condition.

As agricultural education and enterprise extend, fixed rotations will be less regarded. The market-gardener, who extracts a great deal more from his land than the farmer has hitherto been able to do, does not adhere to any definite system of cropping. If the farm is kept clean and in improving condition, there can be no harm in growing whatever crops it is adapted to produce. Cropping clauses are only requisite during the three or four last years of a tenancy. The restrictions found in some agreements, preventing the growth of clover for seed, flax, and even potatoes, are inadmissible. Equally objectionable are clauses against the sale of particular sorts of produce, such as hay or roots.

The farmer, if he is fit to be intrusted with the use of the land, ought to be permitted to grow or sell off any crop he pleases, provided an equivalent in manure be brought back. On well-cultivated land, in good condition, it is now the practice of the best farmers to take oats or barley after wheat; indeed, some of the best malting barley in Essex, on the Scottish carse-lands, and elsewhere, is now grown after wheat. The frequent growth of cereals, and the heaviest of hay and root crops, even when removed from the farm, may be fairly compensated for by large doses of town-dung or of sewage. The plant-food disposed of in the more ordinary sales of the farm is economically restored by the use of bones or superphosphate, guano or nitrate of soda, or by keeping-plenty of sheep, penning them over the land, and supplying them liberally with cake and corn.

PERFU’MERY, PE’RFUMES (Fr. perfum, from Lat. fumus, smoke or vapor), delicate fumes or smells. Perfumes are of three distinct classes when derived from plants, and there is a fourth class, which are of animal origin.

CLASS I.—These are the most ancient, and have been in use from the earliest period of which there is record. They consist of the various odoriferous gum-resins, which exude naturally from the trees which yield them; and to increase the produce, the plants are often purposely wounded. The most important are benzoin, olibanum, myrrh, and camphor. No less than 5000 cwt. of these together are annually imported into Britain. Gum-resins form the chief ingredients in ‘ Incense,’ (q. v.), and in Pastilles (q. v.)

CLASS II. are those perfumes which are procured by distillation. As soon as the Greeks and the Romans learned the use of the still, which was an invention imported by them from Egypt, they quickly adapted it to the separation of the odorous principle from the numerous fragrance-bearing plants which are indigenous to Greece and Italy. An essential oil or otto thus procured from orange-flowers bears in commerce to this day the name of Neroly, supposed to be so named after the Emperor Nero. Long before that time, however, fragrant waters were in use in Arabia. Odor-bearing plants contain the fragrant principle in minute glands or sacs; these are found sometimes in the rind of the fruit, as the lemon and orange; in others, it is in the leaves, as sage, mint, and thyme; in wood, as rosewood and sandal-wood; in the bark, as cassia and cinnamon; in seeds, as caraway and nutmeg. These glands or bags of fragrance may be plainly seen in a thin cut stratum of orange-peel; so also in a bay leaf, if it be held up to the sunlight, all the oil cells may be seen like specks. All these fragrant-bearing substances yield by distillation an essential oil peculiar to each; thus is procured oil of patchouly from the leaves of the patchouly plant, Pogostemon patchouly. a native of Burmah; oil of caraway, from the caraway seed; oil of geranium, from the leaves of the Geranium rosa; oil of lemon, from lemon-peel; and a hundred of others of more infinite variety.

The old name for these pure odoriferous principles was Quintessence. Latterly, they have been termed Essential Oils; they are now, in modern scientific works, often termed Ottos, from the Turkish word attar, which is applied to the well-known otto or attar of roses. See oil.

All the various essential oils or ottos are very slightly soluble in water, so that in the process of distillation the water which conies over is always fragrant. Thus, elder water, rose water, orange water, dill water are, as it were, the residue of the distillation for obtaining the several ottos. The process of Distillation (q. v.) is very simple; the fragrant part of the plant is put into the still and covered with water; and when the water is made to boil, the ottos rise along with the steam, are condensed with it in the pipe, and remain floating on the water, from which they are easily separated by decanting. In this way 100 pounds of orange, lemon, or bergamot fruit peel will yield about 10 ounces of the fragrant oil; 100 pounds of cedar wood will give about 15 ounces of oil of cedar; 100 pounds of nutmeg will yield 60 to 70 ounces of oil of nutmeg; 100 pounds of geranium leaves will yield 2 ounces of oil.

Every fragrant substance varies in yield of essential oil. The variety of essential oils is endless; "but there are a certain relationship among odors as among tints. The lemon-like odors are the most numerous, such as verbena, lemon, bergamot, orange, citron, citronella; then the almond-like odors, such as heliotrope, vanilla, violet; then spice odors, cloves, cinnamon, cassia. The whole may be classified into twelve well-defined groups. All these ottos are very soluble in alcohol, in fat, butter, and fixed oils. They also mix with soap, snuff, starch, sugar, chalk, and other bodies, to which they impart their fragrance.

The principal consumption of the various fragrant ottos is for scenting soap. Windsor soap, almond soap, rose soap, and a great variety of others, consist of various soaps made of oil and tallow, perfumed while in a melted state with the several named ottos or mixtures of them.

Though snuff is by no means so popular an article in the reign of Victoria as it was in Anne’s time, yet the increased population, and the extended exports to colonies, cause a production of scented snuff positively greater now than fifty years ago; and it is especially in demand in the fur countries of Northern Canada. There is a large consumption of fragrant essential oils in the manufacture of toilet powders; under the various names of rose powder, violet powder, &c., a mixture of starch and orris, differently scented, is in general demand for drying the skin of infants after the bath.

Precipitated chalk and powdered cuttle-fish bone, being perfumed with otto of roses, powdered myrrh, and camphor, become ‘ Dentrifice.’ The ottos of peppermint, lavender, rose, and others, are extensively used in scenting sweetmeats and lozenges.

More than 200,000 pounds weight of various ottos have been imported into Britain in one year, and valued at over £180,000; to this must be added at least one-third as much again distilled in England. Of the imported articles enumerated, oils of lemon and bergamot, from the Two Sicilies, reached 128,809 pounds, valued at £57,054.

class III.—These are the perfumes proper, such as are used for perfuming handkerchiefs, &c. Contrary to the general belief, nearly all the perfumes derived from flowers are not made by distillation, but by the processes of enfleurage and maceration. Although this mode of obtaining the odors from flowers has certainly been in practice for two centuries in the valley of the Var, in the south of France, it is only by the publication of a recent work* [*Art of Perfumery, by Septimus Piesse, Ph. D., 8vo. 50 cuts. Longman. 4th] that the method has been made generally known. The odors of flowers do not, as a general rule, exist in them as a store or in a gland, but are developed as an exhalation. While the flower breathes it yields fragrance, but kill the flower, and fragrance ceases. It has not been ascertained when the discovery was made of condensing, as it were, the breath of the flower during life; what we know now is, that if a living flower be placed near to grease, animal fat, butter, or oil, these bodies absorb the odor given off by the blossom, and in turn themselves become fragrant. If we spread fresh unsalted butter upon the bottom of two desert-plates, and then fill one of the plates with gathered fragrant blossoms of clematis, covering them over with the second greased plate, we shall find that after 24 hours the grease has become fragrant. The blossoms, though separated from the parent stem, do not die for some time, but live and exhale odor; which is absorbed by the fat. To remove the odor from the fat, the fat must be scraped off the plates and put into alcohol; the odor then leaves the grease and enters into the spirit, which thus becomes ’scent,’ and the grease again becomes odorless.

The flower fanners of the Var follow precisely this method on a very large scale, with but a little practical variation, with the following flowers—rose, orange, acacia, violet, jasmine, tuberose, and jonquil. The process is termed enfleurage. In the valley of the Var, there are acres of jasmine, of tuberose, of violets, and the other flowers named; in due season the air is laden with fragrance, the flower harvest is at hand. Women and children gather the blossoms, which they place in little panniers like fishermen’s baskets hung over the shoulders. They are then carried to the laboratory of flowers and weighed. In the laboratory the harvest of flowers has been anticipated. During the previous winter great quantities of grease, lard, and beef-suet have been collected, melted, washed, and clarified. In each laboratory there sire several thousand chassis (sashes), or framed glasses, upon which the grease to be scented is spread, and upon this grease the blossoms are sprinkled or laid. The chasse en -verve is, in fact, 41 frame with a glass in it as near as possible like a window-sash, only that the frame is two inches thicker, so that when one chasse is placed on another, there is a space of four inches between every two glasses, thus allowing space for blossoms. The illustration shows the chasse with grease and flowers upon it (fig. 1), also a pile of the same as in use. The flower blossoms are changed every day, or every other day, as is convenient in regard to the general work of the laboratory or flowering of the plants. The same grease, however, remains in the chasse so long as the particular plant being used yields blossoms. Each time the fresh flowers are put on, the grease is ‘ worked ‘—that is, serrated with a knife—so as to offer a fresh surface of grease to absorb odor. The grease being enfleuree in this way for three weeks or more—in fact, so long as the plants produce blossoms—is at last scraped off the chasse, melted, strained, and poured into tin canisters, and is now fit for exportation. Fat or oil is perfumed with these same flowers by the process of maceration; that is, infusion of the flowers in oil or melted fat. For this end, purified fat is melted in a bain marie, or warm bath, and the fresh blossoms are infused in it for several hours. Fresh flowers being procured, the spent blossoms are strained away, and new flowers added repeatedly, so long as they can be procured.

The bain marie is used in order to prevent the grease becoming too hot from exposure to the naked tire; so long as the grease is fluid, it is warm enough. Oil does not require to be warmed, but improved results are obtained when it is slightly heated.

Jasmine and tuberose produce best perfumed grease by enfleurage, but rose, orange, and acacia, give more satisfactory products by maceration; while violet and jonquil grease is best obtained by the joint processes—enfleurage followed by maceration. In the engraving a. chasse en fer (2, fig. 1) is shown; this is for enfleurage of oil. In the place of glass, the space is filled with a wire net; on which is laid a molleton, or thick cotton fabric—moleskin, soaked with oil; on this the flowers are laid, just as with solid grease. In due time—that is, after repeated changing the flowers —the oil becomes fragrant, and it is then pressed out of the moleskin cloth. Oil of jasmine, tuberose, &c., are prepared in this way. In order now to obtain the perfume of these flowers in the form used for scenting handkerchiefs, we have only to infuse the scented fat or oil, made by any of the above methods, in strong alcohol.

In extracting the odor from solid fat it has to be chopped up fine as suet is chopped, put into the spirit, and left to infuse for about a month. In the case of scented oil it has to be repeatedly agitated with the spirit. The result is, that the spirit extracts all the odor, becoming itself ‘ perfume,’ while the grease again becomes odorless; thus is procured the essence of jasmine, essence of orange flowers, essence of violets, and others already named, rose, tuberose, acacia, and jonquil.

It is remarkable that these flowers yield perfumes which, either separate or mixed in various proportions, are the types of nearly all flower odors; thus, when jasmine and orange flowers are blended, the scent produced is like sweet pea; when jasmine and tuberose are mixed, the perfume is that of the hyacinth. Violet and tuberose resemble lily of the valley. All the various bouquets and nosegays, such as ‘ frangipanni,’ ‘white roses,’ ’sweet daphne," are made upon this principle.

The commercial importance of this branch of perfumes may be indicated by the quantity of flowers annually grown in the district of the Var. Flower Harvest: orange blossoms, 1,475,000 lbs.; roses, 530,000 lbs.; jasmine, 100,000 lbs.; violets, 75,000 lbs.; acacia, 45,000 lbs.; geranium, 30,000 lbs.; tuberose, 24.000 lbs. jonquil, 5000 lbs.

class IV. Perfumes of animal origin.—The principal are Musk (q. v.), Ambergris (q. v.), Civet (q. v.), and Castor (q. v.) The aroma of musk is the most universally admired of all perfumes; it freely imparts odor to every body with which it is in contact. Its power to impart odor is such, that polished steel will become fragrant of it if the metal be shut in a box where there is musk, contact not being necessary.

In perfumery manufacture, musk is mixed with other odorous bodies to give permanence to a scent. The usual statement as to the length of time that musk continues to give out odor has been called in question. If fine musk be spread in thin layers upon any surface, and fully exposed to a changing current of air, all fragrance, it is said, will be gone in from six to twelve months.

Civet is exceedingly potent as an odor, and when pure, and smelled at in the bulk of an ounce or so, is utterly insupportable from its nauseousness; in this respect it exceeds musk. When, however, civet is diluted so as to offer but minute quantities to the olfactories, then its perfume is generally admitted; this is so with gas-tar; but the fragrant principle is the same as that breathed by the beautiful narcissus. Castor is in our day almost obsolete as a perfume.

The average importation of musk per annum for a period of five years was 9388 ounces, value £10,688; export 1578 ounces, value £2143; leaving for home-consumption every year 7810 ounces, value £8545. Average importation per annum for a similar period; otto of roses 1117 ounces, value £13,561; vanilla 3525 pounds, value £12,568; ambergris 225 ounces, value £225; civet 355 ounces, value £300; orris root 420 hundredweight.

The works on perfumes are very few; that of Madame Celnart, in the Libraire Roret, is most worthy of notice among the French; a translation of it has been made by Mr. C. Morflt of Philadelphia. In England. The British Perfumer, by C. Lilly (1822), was the only work of the kind published in England prior to the Art of Perfumery by S. Piesse (1855). See also Rimmel’s Book of Perfumes (1875).