Flax, or Limim, L. an indigenous plant, consisting of four species, of which the following are the principal:

1. The Usitatissimum, or Common Flax, which grows in corn-fields, and sandy pastures, and flowers in the month of July. - . This valuable plant thrives most luxuriantly on ground newly broken up; which it ameliorates, if it be sown only every sixth year. The best preparatory crops for flax are those of hemp and potatoes. In the fens of Lincolnshire, hemp is sown the first year, on a good free open loam, that has been well tilled, the soil being properly manured with pigeon's dung; the second year again hemp is cultivated without any manure ; and, in the succeeding year followed by flax.

With respect to the quality of linseed, from which flax is propagated, that imported from Riga is generally supposed to be the best, and is sown broad-cast with clover, in the proportion of 2, or 21/2 bushels per acre. Experience, however, has evinced, that any other seed would be equally successful, if it were properly kept for six or seven years, before it is sown ; for the merchants of Riga frequently import linseed from Germany and other Countries, which, after seve-ral years, they again furnish with the same seed, but at an advanced price. It would farther be an useful practice, to exchange linseed among farmers living at some distance ; as it has been observed that it improves, when cultivated in a different soil and climate. - See also Linseed.

In order to prevent the depredations of birds on this valuable seed, circumspect farmers sow it after sun-set on land well pulverized, and harrow it in early the next morning, before the sun rises.— Thus the seed, being moistened by the night's dew, is easily enveloped with earth, and rendered invisible to birds. - Another great enemy to the prosperity of the flax-plant, is the parasitical weed called the Greater Dodder (which see), or Cuscu-ta Europcea, L. - Bechstein communicates the following remedy, by which it may be easily and completely extirpated : - To every bushel of linseed, take two drams of camphor reduced to powder, by adding fifteen drops of spirit of wine ; and mix it well with the seed on the evening when it is to be sown.

As soon as the crop attains the height of four inches, it will be requisite to weed it; an operation which ought to be performed with the greatest care, that the flax may not be trodden down. If it be allowed to grow longer, the stalks will be so much bent and broken, that they never regain their former straightness. When the weeds are carefully eradicated, they should be carried off the field, and on no account be suffered to lie in the furrows, because they often strike root again, and thus injure the growth of the flax.

This plant becomes ripe when it is in full blossom ; but, if it be intended to stand for seed, it will not attain to maturity till the milky juice which it affords is dried up ; at which time it is to be pulled, in order to be prepared for the manufacturer.

The first process which flax undergoes, is that of rating, or steeping it in water, to loosen and separate the rind from the stalk. The early flax is generally watered by laying it in bundles, in a pond or reservoir of soft water, where it is pressed down by stones, or other heavy bodies. In the course of a week, the rind will be sufficiently loosened, when the flax ought to be removed from the water, spread out in the air, and dried. Great skill and precaution are necessary in this part of the operation; for should the flax be left too long in the water, the filaments or threads will become rotten and useless : it will therefore be preferable to take it out rather at an earlier period., than to leave it too long in the pits.

Another process is that of dew-ripening ; which is performed by spreading the flax on the grass, so that the joint action of the rain and dew produces an effect similar to that of rating, in some parts of Germany, it is never steeped in water, but only exposed for several weeks to the air, rain, and sun ; by which it is said to become finer and softer than by any other method.

To these operations may be added that of rippling, namely, the' separating of the seed from the stalk, by passing the flax -through a kind of comb before it is rated or watered. These combs are made of iron, the teeth of which are so closely set together, that the heads cannot pass through, and consequently are pulled off.

Some cultivators, however, beat the seed out in the field where it grew, instead of rippling, by means of a heavy piece of wood fastened to a bundle; after which it is sifted clean, into a large sheet.

In this state the flax is ready to be manufactured into Linen; for a short account of which process, we refer the reader to that article.

Many attempts have been made by ingenious persons, to improve flax, or to render it finer, softer, and equal to silk in spinning. In Ireland, this obje6t has, in a great measure, been attained by boiling it for several hours in sea-water, with the addition of a lye made of unslacked lime, and two or three parts of pot-ashes: thus we have seen the coarsest part of flax, or tow, considerably changed in its texture, so as to resemble the finest lint. - In the 69th Report of the Economical Society of Leipzig, printed in 1797 (in German), we meet with the following process of converting flax into a silky sub-stance, communicated by Count Harrsch, director of the mines in Russia: Take pure combed flax, tie it up into rollers covered with white buckram, fasten them with packthread, and deposit them for a fortnight in a damp cellar. Then open the flax, and place it under the cylinders of a common mangle, where it should be rolled over five or six times, in a manner similar to that pursued with linen. Next, the flax should be passed through a fine brass comb. This process of mangling and combing must be repeated a second and third time, but the combs ought to be progressively finer. By such treatment (the Count informs the Society) a very fine, tender, and glossy flax, may be obtained, scarcely inferior to China silk ; and, though it loses more than one-third of its substance, yet the refuse, or tow, is uncommonly fine, and still useful for the manufacture of ordinary linen.

He farther observes, that, after each combing, particularly the first, the filaments appear flat and com-pressed, but that they recover their roundness by the subsequent operation. Flax thus prepared cannot, by mere contact, or the sense of feeling, be distinguished from silk, and is fit to be manufactured into the finest cambric, and Brabant lace.

Of the utility of flax or linseed, in fattening cattle, we have already treated in vol. i. p. 453.

Beside these various purposes, flax may also be considered as a manure: for the land on which it is spread, in order to prepare it for housing, is thus in a considerable degree ameliorated ; and, if rated flax be laid on a coarse, sour pasture, the nature of the herbage will be totally changed ; and the sweet-est grasses will in future grow on. such indifferent soil. - The water, too, in which the flax is immersed, if properly sprinkled on land, by means of watering carts, will produce a very fertilizing effect, and increase its value ten or fifteen shillings per acre. But this water is of so poisonous a nature to cattle, that the pra6tice of macerating or steeping flax, in any pond or running stream, is, by the 33d Henry VIII. c. 1/. prohibited under very severe penalties.

2. The catharticum, or Purging Flax, or Mill-mountain, is an annual plant, growing in dry meadows and pastures, and flowering from June to August. It is eaten by horses, sheep, and goats. - An infusion of two drams of the dried plant is an excellent laxative, and has been given with advantage in obstinate rheumatisms.