in a state of crystallization. In the Peruvian mines, it is found in a form somewhat resembling fern-leaves; this figure is caused by a number of eight-sided crystals, so placed over each other as to give it a vegetable appearance. It sometimes assumes the form of round, rather crooked threads, varying from the thickness of a finger to that of a hair. It is rarely found in a state of purity, being frequently mixed with gold, mercury, copper, tin, iron, and lead.

Silver is sometimes found in combination with sulphur, arsenic, and other substances: when mineralized by sulphur alone, it forms the vitreous silver ore, which assumes a great variety of colours; when united to sulphur and arsenic, the mass becomes the ruby-like ore, varying in colour from deep red to dark gray in proportion to the prevalence of either of these substances.

Silver is found both in the primitive and secondary earths, and is frequently imbedded in quartz, jasper, hornstone, and chalk. It is chiefly met with in Sweden, Norway, and the polar latitudes; when it occurs in hot climates, it is generally amidst mountains covered with perpetual snows.

The richest and most important silver mines in Europe are those of Königsberg in Norway; they are situated in a mountainous district, and divided into superior and inferior, according to their relative position; the beds in which the silver is found run from north to south. These mines are of considerable depth, and enormous masses of native silver are said to have been found in them.

The French mines are not so remarkable for the richness of their silver ore as for the other minerals they contain. That of Allemont, ten leagues from Grenoble, is one of the principal; it is situated at the height of nearly 3,000 feet above the level of the sea; the veins near the surface were the richest in silver. This mine is now abandoned.

The most celebrated of the Spanish silver mines is that of Guadalcanal, in Andalusia, situated in the Sierra

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F

Morena, a few miles to the north-east of the quick-silver mine of Almaden; it was well-known to the Romans, and formerly very productive. This mine furnishes the ruby-ore.

Silver, however, is most abundant in the centre of the Andes; for here we find the celebrated mountain of Potosí; it is of immense height, and said to be penetrated with veins in every direction. When first discovered in 1545, the veins were nearly all of pure silver, latterly, however, little more than five drams were obtained from one hundredweight of ore. In the space of ninety-three years from its discovery, the number of ounces of silver extracted from this mountain is calculated to have been no less than four hundred millions.

Among the American mines those of Mexico must not be forgotten; that of Valenciana, in the district of Guanaxuato, is one of the richest; the vein traverses a slaty mountain, and abounds with silver, both native and mineralized. The mine is of great depth, and is supposed to contain a greater quantity of silver than all the other mines of that country.

Silver possesses all the properties of other perfect metals; it is fixed and unalterable in the fire of any ordinary furnace, but may be volatilized, being sometimes found in the soot of chimneys where large quantities are melted. When exposed to the focus of a large burning-glass, it evaporates in a fume, which rises to the height of five or six inches, and will completely silver a plate of metal.

With the exception of gold, silver is the most ductile of all metals; a single grain may be extended into a plate of one hundred and twenty-six inches long, and half an inch broad; if reduced into leaves under the gold beater's hammer, it is capable of still further extension; its tenacity, however, bears no proportion to its ductility, being less than even that of iron or copper. A silver wire, one tenth of an inch thick, will scarcely bear a weight of two hundred and seventy pounds, while a gold wire of the same thickness will support nearly double that weight.-Saturday Magazine.

HAND-WEAVING.

THERE is, perhaps, no art more generally practised, nor any which has conduced more to the comfort of mankind, than that of weaving, and its antiquity is so great, that to endeavour to trace out the original inventor, would be a hopeless task. The principle of weaving is the same in every kind of fabric, and consists in forming any description of fibres into a flat web, or cloth, by interlacing one with another; the various appearances of the manufacture arise as much from the different modes in which these fibres are interwoven, as from the difference of material.

The simplest weaving loom, although far from being in reality a complicated machine, is yet necessarily formed of so many pieces, that any view that can be given of it would be insufficient to render the process intelligible.

The material which forms the length of the cloth is called the warp, and the various threads of which it is composed are wound singly round small wooden reels called bobbins. A certain number of these is taken by the warper, who prepares the threads for the weaver, and who arranges the bobbins. The number of bobbins taken up at one time in silk-weaving is fifty, twentyfive of which are placed on the lower beam, and as many on the upper; the thread from the bottom row passes over the lower bar, and that from the upper over the upper bar; these threads are then tied together, passed between two pulleys to the warping mill, on which the warp has now to be wound, and there placed on a pin. The warper now passes her fingers between the threads of the warp, taking, alternately a thread from the upper and lower row of bobbins, and slides her hand along, until she reaches the pin over which the ends of the warp, which are tied together, are passed. They are then wound on a roller, side by side, and to the "loom" or machine for weaving, through which

they run, also side by side. Near the end they are attached to "healds," or threads stretched in an upright frame, with loops in their centres. In plain weaving, a pair of these frames is used, one half the threads of the warp passing through the one frame, and the other halı through the other, alternately, thus-first a thread is passed through the loop of one heald, and then the next goes through a loop of the other heald, and so on. These healds are so fixed that they can be raised alternately-one raising every alternate thread.

The warp upon the cylinder having been equally spread over its surface, and two long sticks introduced between its alternate threads, to supply the place of the two pins on the warping-mill, it is now prepared for the weaver, by straining it tight, by means of weights properly applied at one end. Machinery which is connected with treadles, which the weaver presses with his foot alternately, raises first one half of the threads of the warp and then the other, each time so far separating them as to allow the shuttle to pass, and carry with it the cross threads of the cloth, called the woof. The thread of the woof, which crosses the cloth, is wound round the pointed bobbin in the inside of the shuttle, and as this is thrown with a sudden jerk, between the separated threads of the warp, of course it unwinds, and the shuttle passes on to the other side of the cloth; the threads of the warp are again shifted by the treadles, and the shuttle is returned, forming the second thread of the woof, and this raising and depressing the alternate threads of the warp, and passing and repassing of the shuttle, is continued, until the piece of cloth is finished; this is called plain weaving, and the threads of the warp and woof would appear, if magnified, quite intri

cate.

In some kinds of work, instead of the woof passing between every other thread of the warp, it will pass under one and over three; it is in this case called twill, and this kind of fabric is considered stronger than plain weaving, from the threads of the woof lying closer together. There is another kind of tweel, in which the

thread of the woof is of a different colour to that of the warp, this produces a pattern. In some instances the threads are made to cross each other in a peculiar manner, producing different kinds of fabrics, as mail-net and gauze; here, at each place where the threads cross, they are curiously twisted or tied. In this the machinery of the loom is much more complicated, and the treadles that separate the warp more numerous.

In the weaving of carpets the warp is double, and the thread of the woof passes from the upper to the lower portion at various points, according to the pattern; in the smaller patterns, these points are more numerous than in the larger, and consequently, a carpet of a smal! pattern is (the quality of thread being equal) considerably stronger and more durable, than one in which the design is of a larger character. The weaving of damask patterns is extremely complicated, and the preparing the warp to receive the woof, and calculating the order in which the woof is to be thrown, will employ a man for six weeks or two months.

In the weaving of cotton goods, a preparation of flour and water is used, for the purpose of giving consistency to the thread of the warp; this preparation is applied by means of a large brush, as it is necessary that the warp should be kept constantly moist and pliable, and in extremely hot weather, there is much difficulty in producing this effect. The silk weavers, in Spitalfields, had a curious method of keeping the warp in this state; instead of flour and water, a kind of size was prepared by boiling cuttings of kid-leather in water; this is called sprew: the workman takes a quantity of this liquid into his mouth, and blows it through his lips in such a manner, as to make it fall upon the warp in the form of a fine rain.

There is no doubt, that the complicated machinery employed in the English looms, can produce the finest and most beautiful fabrics in the world; but while we look with amazement at the result of the labours of our countrymen, we cannot withhold our astonishment at the elegance and regular texture of the goods produced