great richness and variety of notes, and extraordinary power in imitating sounds. F. canaria, or canary finch. These birds constitute, to some little extent, an article of commerce, being exported from the Tyrol in considerable numbers every year to various other parts of Europe. Buffon enumerates no fewer than 29 varieties, and devotes 50 pages of his celebrated work to an interesting detail of their manners, habits, and song. They are bred and reared in England in aviaries with great facility; and the fidelity of their attachments, and delicacy of their attentions, their extreme neatness, parental affection, and animated and almost incessant music, constitute a source of pure and exquisite entertainment to all the admirers of artless and interesting nature. F. linaria, or the linnet, is to be met with in every part of Europe, and is particularly common in England, where it builds, generally, in thorns and furze bushes, and breeds twice in the year. Linnets feed on various seeds; but particularly relish those of the flax plant, from the Latin name for which (linum) they probably derive their name. They can be taught the notes of various other birds, and even to utter words with very distinct enunciation; but their natural song, expressive of tranquillity and rapture, and poured out in a strain of richly varied melody, is infinitely superior to these unmeaning and elaborate articulations. For the red-pole and the mountain-sparrow, see Aves, Plate VI. fig. 7 and 8.

FRIT, in the glass manufacture, the matter or ingredients whereof glass is to be made, when they have been calcined or baked in a furnace; or it is the calcined matter to be run into glass. See GLASS.

FRITILLARIA, in botany, imperial fritillary, or crown imperial, a genus of the Hexandria Monogynia class and order. Natural order of Coronaria. Lilia, Jussieu. There are five species with many varieties.

FRIZING of cloth, a term in the woollen manufactory, applied to the forming of the nap of a cloth, or stuff, into a number of little hard burrs or prominences, covering almost the whole ground thereof. Some cloths are only freezed on the backside, as black cloths; others on the right side, as coloured and mixed cloths, rateens, bays, freezes, &c. Frizing may be performed two ways; one with the hand, that is, by means of two workmen, who conduct a kind of plank that serves for a frizing instrument.

The other way is by a mill, worked either by water, or a horse, or sometimes by men. This latter is esteemed the better way of frizing, by reason the motion being uniform and regular, the little knobs of the frizing are formed more equably and regularly. The structure of this useful machine is as follows:

The three principal parts are the frizer or crisper, the frizing-table, and the drawer, or beam. The two first are two equal planks or boards, each about ten feet long, and fifteen inches broad, differing only in this, that the frizing-table is lined or covered with a kind of coarse woollen stuff, of a rough sturdy nap; and the frizer is incrustated with a kind of cement composed of glue, gum arabic, and a yellow sand, with a little aquavitæ, or urine. beam, or drawer, thus called, because it draws the stuff from between the frizer and the frizing-table, is a wooden roller, beset all over with little, fine, short points, or ends of wire, like those of cards used in carding of wool.

The

The disposition and use of the machine is thus the table stands immoveable, and bears or sustains the cloth to be frized, which is laid with that side uppermost on which the nap is to be raised over the table is placed the frizer, at such a distance from it as to give room for the stuff to be passed between them, so that the frizer, having a very slow semicircular motion, meeting the long hairs or naps of the cloth, twists and rolls them into little knobs or burrs, while, at the same time, the drawer, which is continually turning, draws away the stuff from under the frizer, and winds it over its own points..

All that the workman has to do while the machine is a going, is to stretch the stuff on the table, as fast as the drawer takes it off; and from time to time to take off the stuff from the points of the drawer. The design of having the frizing-table lined with stuff of a short, stiff, stubby nap, is, that it may detain the cloth between the table and the frizer long enough for the grain to be formed, that the drawer may not take it away too readily, which must otherwise be the case, as it is not held by any thing at the other end.

FROG. See RANA.

FRONDESCENTIA, in botany, a term expressive of the precise time of the year and month, in which each species of plants unfolds its first leaves. All plants produce new leaves every year; but all do not re

new them at the same time. Among woody plants, the elder, and most of the honeysuckles; among perennial herbs, crocus and tulip, are the first that push or expand their leaves. The time of sowing the seed decides with respect to annuals. The oak and ash are constantly the latest in pushing their leaves; the greatest number unfold them in spring; the mosses and firs in winter. These striking differences, with respect to so capital a circumstance in plants as that of unfolding their leaves, seem to indicate that each species of plant has a temperature proper or peculiar to itself, and requires a certain degree of heat to extricate the leaves from their buds, and produce the appearance in question. This temperature, however, is not so constant as, to a superficial observer, it may appear to be. Among plants of the same species, there are some more early than others; whether that circumstance depends, as it most commonly does, on the nature of the plants, or is owing to differences in heat, exposure, and soil. In general, it may be affirmed, that small and young trees are always earlier than larger or old ones. See GERMINATION, and Milne's Bot. Dict.

FROST, such a state of the atmosphere as causes the congelation or freezing of water or other fluids into ice. In the more northern parts of the world, even solid bodies are affected by frost, though this is only or chiefly in consequence of the moisture they contain, which being frozen into ice, and so expanding as water is known to do when frozen, it bursts and rends any thing in which it is contained, as plants, trees, stones, and large rocks. Many fluids expand by frost, as water, which expands about th part, for which reason ice floats in water; but others again contract, as quicksilver, and thence frozen quicksilver sinks in the fluid metal.

Frost, being derived from the atmosphere, naturally proceeds from the upper parts of bodies downwards, as the water and the earth so, the longer a frost is continued, the thicker the ice becomes upon the water in ponds, and the deeper into the earth the ground is frozen. In about 16 or 17 days frost, Mr. Boyle found it had penetrated 14 inches into the ground. At Moscow, in a hard season, the frost will penetrate two feet deep into the ground; and Captain James found it penetrated 10 feet deep in Charlton Island, and the water in the same island was frozen to the depth of six feet. Sheffer assures us, that in Sweden the frost pierces

two cubits, or Swedish ells into the earth, and turns what moisture is found there into a whitish substance, like ice; and standing water to three' ells or more. The same author also mentions sudden cracks or rifts in the ice of the lakes of Sweden, nine or ten feet deep, and many leagues long; the rupture being made with a noise not less loud than if many guns were discharged together. By

such means however the fishes are furnished with air; so that they are rarely found dead.

The natural history of frosts furnish very extraordinary effects. The trees are often scorched and burnt up, as with the most excessive heat, in consequence of the separation of water from the air, which is therefore very drying. In the great frost in 1683, the trunks of oak, ash, walnut, &c. were miserably split and cleft, so that they might be seen through, and the cracks often attended with dreadful noises like the explosion of fire arms. Philos. Trans. Number 165.

The close of the year 1708, and the beginning of 1709, were remarkable throughout the greatest part of Europe, for a severe frost. Dr. Derham says, it was the greatest in degree, if not the most universal in the memory of man; extending through most parts of Europe, though scarcely felt in Scotland or Ireland.

In very cold countries, meat may be preserved by the frost six or seven months, and prove tolerably good eating. See Captain Middleton's observations made in Hudson's Bay, in the Philos. Trans. Number 465,

sect. 2.

In that climate the frost seems never out of the ground, it having been found hard frozen in the two summer months. Brandy and spirit, set out in the open air, freeze to solid ice in three or four hours.

Lakes and standing waters, not above 10 or 12 feet deep, are frozen to the ground in winter, and all their fish perish. But in rivers where the current of the tide is strong, the ice does not reach so deep, and the fish are preserved. Id. ib.

Some remarkable instances of frost in Europe, and chiefly in England, are recorded as below; in the year

220 Frost in Britain that lasted five