E), might serve as a reservoir of pure water, that could either be decanted, or drawn off by means of a cock applied to the centre of the machine, marked F. We think, however, this latter arrangement, which is proposed by M. Parrot, in many respects objectionable, and therefore advise the reader to make use of the more simplified construction. Hence we shall only add, that every filtering machine ought to be provided with a cloth cover, to prevent the dust from rising with the water, without impeding its filtration.
It is needless to expatiate on the great advantages of filtering machines in the different processes of dyeing, baking, brewing, distilling, and all the domestic arts. As no particle of real nutriment can be assimilated to the human fluids, without being previously macerated and reduced by water (whether this fluid be introduced into the stomach, in the form of beer, wine, spirits, tea, &c.) it will be easily understood that impure water cannot fail to produce, however slowly, many dangerous, and often incurable diseases—the source of which is seldom suspected.—See Water.
FINCH, or Fringilla, L. a genus of birds, comprising one hundred and eight species, of which ten only are natives of this country; the principal of these are mentioned in their alphabetical order.—See Canary-bird, Gold-finch, Linnet, Sparrow, &c.
Fining: See Clarification.
FIR-TREE, the name of several species of the Pinus, or pine-tree, of which the following are the principal:
1. The sylvestris, or Scotch fir, which is a native of Scotland, and flourishes best in a poor sandy soil, especially if it be mixed with loam: on rocks or bogs it seldom attains a large size; if planted in a black soil, it becomes diseased; and, on chalk-lands, it perishes.
This species of fir thrives most luxuriantly on the north and east sides of hills, where it not only grows more rapidly, and attains a greater height, but the grain of its wood is also more compact, and the trees are fuller of sap than if they had been planted in another direction.
The Scotch fir is propagated from seeds, which are obtained from the cones of fruit it produces. The proper time of sowing is in the latter end of March, or beginning of April: it the seeds be set in a grove, the tree becomes tall and naked; if in open situations, exposed to the sun, it becomes branched. At the age of four years, it is to be transplanted to the place where it is intended to remain; during which operation the utmost caution should be taken, that the central or tap-root be not broken off, or in any manner impeded in its growth; as, in that case, the stem would cease to shoot upwards, and the tree remain a dwarf. But, notwithstanding every care taken by the industrious planter, his hopes are often frustrated by predatory animals, such as squirrels, that strip the whole bark off the young tree, in consequence of which it dies, and is broken by the first high wind. The hare is another enemy to young firs, though less dangerous: it is affirmed that hares may be drawn away from them, by sowing in their vicinity the Cytisus Laburnum, a species of the Bane-trefoil, the young shoots of which they prefer to firs.
