This is a method[1] which has been employed by the outposts of armies, and by shepherds, on occasions when there has not been a stone at hand to strike fire with. Two pieces of wood are rubbed briskly together, and the friction soon sets them on fire; which is caught on dry and inflammable substances, fun- guses and leaves being found to ignite the most readily. There is nothing superior to the wood of the ivy for rubbing against, or to that of the laurel for rubbing with. A species of wild vine,[2] too—not the same as the labrusca—which climbs up other trees like the ivy, is highly approved of. The coldest[3] woods of all are those of the aquatic trees; but they are the most flexible also, and for that reason the best adapted for the construction of bucklers. On an incision being made in them, they will contract immediately, and so close up their wounds, at the same time rendering it more difficult for the iron to penetrate: in the number of these woods are the fig, the willow, the lime, the birch, the elder, and both varieties of the poplar.

The lightest of all these woods, and consequently the most useful, are the fig and the willow. They are all of them employed, however, in the manufacture of baskets and other utensils of wicker-work; while, at the same time, they possess a degree of whiteness and hardness which render them very well adapted for carving. The plane has considerable flexibility, but it is moist and slimy like the alder. The elm, too, the ash, the mulberry, and the cherry, are flexible, but of a drier nature; the wood, however, is more weighty. The elm is the best of all for retaining its natural toughness, and hence it is more particularly employed for socket beams for hinges, and cases for the pannelling of doors, being proof against warping. It is requisite, however, that the beam to receive the hinge should be inverted when set up, the top of the tree answering to the lower hinge, the root to the upper. The wood of the palm and the cork-tree is soft, while that of the apple and the pear is compact. Such, however, is not the case with the maple, its wood being brittle, as, in fact, all veined woods are. In every kind of tree, the varieties in the wood are still more augmented by the wild trees and the males. The wood, too, of the barren tree is more solid than that of the fruit-bearing ones, except in those species in which the male trees[4] bear fruit, the cypress and the cornel, for instance.