The best mode of seasoning oak is to put it in water. This, if in the log, should be done for a whole year or more, but, if cut in planks, less time is necessary ; in either case, alternate soaking and drying is to be prefer red. This, in planks, is very practicable ; but, in regard to logs, one soaking and drying gradually in the shade, is, on account of the great labour attending the opera tion, most generally practised. After the planks have been soaked in water, they are dried by placing a strong pole in a horizontal position, at such a height as will ad mit of one end of each plank being placed on the ground, and the other resting against the pole edgewise, placing a plank first on one side of the pole, and then another on the other side alternately, thus leaving a space for the air to pass freely and dry them, and being exposed edge wise to the sun, they are not liable to split.
In ash, there is little difference in the quality through 'he whole thickness of the tree, the outside is rather the toughest: it soon rots when exposed to the weather, but vyill last long when protected.
Of elm, some sort will decay sooner than the brown or red. It is improper for roofs or floors, being generally cross-grained, and very liable to warp ; it also shrinks very considerably, not only in breadth, but lengthwise. It answers well when used under water ; it is not liable to split, and bears the driving of bolts and nails better than any other timber.
Beech is hard and close. There is a black or brown, and a white kind : the brown is tough, and sometimes used as a substitute for ash ; it is improper for beams, because a small degree of dampness in the walls very soon rots the ends ; it is fittest for furniture, or where constantly under water.
Poplar is of a very close quality, is liable to the same objections as the beech in beams, but is well adapted for floors and stairs, being not readily inflamed: it rots soon when exposed to the weather.
Ash resembles the poplar in appearance ; it is soft and tough; it lasts when exposed to the weather ; it is equally good through the body of the tree.
The Sycamore and Lime are subject to the same ob jections, in roofing and flooring timbers, as the poplar and beech. The lime is something like the ash, and, like it, is greasy when worked smooth : It is suitable for fur niture.
Birch is equal in quality quite across the body of the tree ; it is very tough, but does not last when exposed to the weather ; it is also subject to be destroyed by the worms.
Chesnut, viz. the sweet, or Spanish, (not the horse chesnut,) is frequently found in old buildings in Eng land ; and although difficult to be distinguished from oak, differs from it in this, that wherever a nail or bolt has been driven into oak before it was dry, a black substance appears round the iron, which is not the case in chcs nut.
The it alnztt-tree is, in Britain, now too valuable to be used in the framings of roofs or floors, and in furniture it has long been superseded by mahogany; it is now used chiefly in stocks of firelocks, fowling-pieces, pistols, Szc.
Mahogany is used chiefly in furniture, but also some times in doors and window sashes; it is sawn out and sea soned by perching out in the winter, and drying in the open air, the use of fire is not advisable. This beautiful timber was introduced into England about the begin ning of the last century : its first application was in a box for holding candles, made by a i\Ir Wollaston for a Dr Gibbons, who had afterwards a bureau of it ; the Duchess of Buckingham had the second bureau. It very soon came into general use. It is divided chiefly into Jamaica and Honduras; the former is by much the hardest and most beautiful : they may be readily distinguished before they arc oiled ; the pores of the Honduras appear quite dark, those of the Jamaica as if filled with chalk.
Fir, being cheaper, and more easily wrought than oak, and next to it in usefulness, is more used in Britain than any other kind of timber. That most generally employ ed in carpentry is distinguished by the name of l‘lemel, (which includes Dantzic and Riga) ; Norway, (which also includes Swedish,) is much used for the smaller timbers, and answers well either when exposed to the air, or under ground. Dranton, or Dram, is suitable for flooring. All these are very durable. American fir is much softer, but suits inside joinery work, such as pan ncls and mouldings. What is termed in England white deal, and in Scotland pine wood, that is, fir deprived of its resinous part, being very durable when kept dry, is much used by cabinet makers ; but, as it will not stand the wea ther, it is little used in carpentry or joinery.
Evelyn makes the following observation on the use of fir That which comes from Bergen, Swinsund, Mott, Longhand, Dranton, (called Dram), being long, straight, and clear, of a yellow and more cedary colour, is esteem ed much before the ,vhite for flooring and wainscot; for masts, those of Prussia, which we call spruce, and Nor way, especially from Gottenburgh, and about Riga, are the best." The tomtits, as Vitruvius terms it, and heart of deal kept dry, rejecting the alburnum or white, is everlast ing; nor is there any wood which so well agrees with the glue, or which is so easy to be wrought. It is also excellent for beams, and other timber work in houses, being both high and exceedingly strong, and therefore of very great use for bars and bolts of doors, as well as for doors themselves ; and, for the beams of coaches, a board of an inch and a half thick will carry the body of a heavy coach with great case, by reason of a natural spring which is not easily injured. It was formerly used for carts and other carriages, and also for the piles to build upon in boggy grounds. Most of Venice and Amster dam is built upon them. For scaffolding also, there is none comparable to it. Under the head of fir may be classed cedar, a wood of great durability, but too expen sive to be used in Britain.