of the fir and pine trees. The smoke is collected upon skins, with which the chimney is lined on purpose to receive it. In England this is made from the dregs at the turpentine houses, but the greatest quantity is imported from Germany, France, Norway, &c. An inferior kind is collected in close vessels, where bones have been burnt.

(45) Frankfort, or German black, is prepared from burnt lees of wine, ground with burnt ivory, bones, or fruit stones.

(46) Bird-lime, a substance procured from the holly, resembles in its properties Indian rubber.

(47) Soap is an unctuous kind of paste, made with oil, or fat substances, and an alkali sometimes actuated with quick lime. The greatest quantity is made in France, Spain, Italy, and Portugal, where olive oil is very plentiful. Next to this oil, tallow is considered the best ingredient, and this, with soda, forms the white soap, and with the addition of resin, the yellow; but there is this difference, that with soda, oils form a hard soap, while potash forms a soft one.

(48) Glass is a transparent brittle factitious substance, produced by the action of fire upon a fixed salt and sand, or stone that readily melts. The materials employed in the manufacture of glass may be

U

reduced under three classes, viz. alkalies, earths, and metallic oxydes. Bottle glass, the coarsest kind, is composed of kelp, or the refuse of soap boilers and common sand. The green colour is owing to the admixture of iron. Flint glass is formed of soda, pounded flints, and oxyde of lead. Window or crown glass contains no lead.

(49) Litharge is the refuse of lead, and is used in the composition of the finer glasses called pastes, designed as imitations of precious stones, it rendering them more solid and brilliant. The base of all artificial stones, is a paste composed of silex, potash, borax, oxyde of lead, and sometimes arsenic. The best silex is obtained from rock crystal, and the next from white sand or flint.

(50) A drop of animal oil laid on an ear-wig, hornet, wasp, &c. will cause their immediate death.

(51) The bone of a very peculiar fish principally inhabiting the Mediterranean Sea. There are several species, but the officinalis, or officinal cuttle contains this bone. It is used as pounce, also by silversmiths, &c. to make moulds for spoons and other small work, being soft, and taking a good impression by merely pressing together with the pattern placed in the centre, also by farmers. The head of the fish appears from between eight kinds of arms, with which they fasten themselves to the

rocks, or seize upon their prey; these are frequently eaten off by the conger eel, but grow again. When taken out of the water they make a noise resembling the grunting of a hog. The eyes when dry resemble pearls, and are sometimes formed into necklaces. Every species emits a black fluid, which when fresh taken, is of a viscid consistence, a peculiar fishy smell, and very little taste; it is preserved for use by being spread round saucers or gallipots so as to dry before putrefaction commences. It is sometimes used for writing ink, and, as a paint, under the name of sepia, and is considered much superior in point of working to Indian ink.

(52) Printing was introduced into England during the reign of Edward the Fourth, by William Caxton; but no certain record has been handed down fixing the precise time when this art received its birth, or to whom to ascribe the honour of the invention.

(53) Gold is the first and most valuable of all metals, not only from its scarcity, but from its admirable properties. It is the hardest and most unalterable of all bodies. It can bear, for two months, being in the hottest fire without any sensible loss in its weight. Its parts are so fine, that a grain of beaten gold can cover fifty square inches, in such a manner that the naked eye may distinguish, on the two surfaces, four millions of particles; and its duc

tility is such that a single grain may be drawn out

to a thread five hundred feet long.

It attains the length

(54) This is a species of the great white shark, a formidable enemy to mariners. of thirty feet and upwards, and frequently weighs from 3 to 4000 lbs. It is principally valued for its oil, and its flesh is eaten in Norway and Iceland, but is coarse and strong.

(55) The zoophites (zoon, an animal, phyton, a plant); or animal plants, are nothing but insects; though by their outward form, their immobility, and their manner of propagating by buds and seeds, they are very like real plants. Their animal nature only shows itself by the sensibility and voluntary motion observed in them. Most of the zoophites hold by a sort of root to the sea, or the waters they live in. Some inhabit stony and chalky places; others are surrounded with a shell, more like horn; and lastly, some are entirely soft and fleshy. The most remarkable of these is the coral structure.

(56) Annealing is the art of tempering, or of heating any thing to bring it to a proper degree of hardness ; or to mix different ingredients so that one part qualifies the other.

(57) The sugar-maple is so called from its juice affording sugar when boiled. It is much cultivated in Ame

rica for this purpose, and to a certain degree in France. A middle-sized tree will yield, without injury to itself, 30 or 40 quarts of juice in the spring, and this quantity will produce a twentieth part its weight of sugar. The wood of the common maple tree is used by turners frequently for musical instruments, being remarkably white, and may be turned so thin as to render it nearly transparent.

(58) Loaf sugar is made from the raw sugar, by lime water being poured upon it, and bullocks blood added instead of whites of eggs. The serum or white part of the blood becomes dissolved, but coagulates when hot, and forms a net-work or strainer, which carries upward all the opposing matters. The scum is removed and boiled with lime water until it becomes transparent. The gross fluid matter that remains after refining sugar, is called treacle or molasses, and no boiling can bring it to a consistence more solid than syrup.

(59) Muriatic acid, or spirit of salt, is colourless when first made, but acquires a pale straw colour by keeping; it forms the salts called muriates, and is used in medicine, the arts, and manufactures. Muriatic acid gas being easily produced by pouring sulphuric acid upon common salt, is a ready and powerful agent in the destruction of infectious matter. The smelling salts are formed of subcar