From time immemorial it has been the practice, particularly in France, to burn the ends of the poles driven into the ground to preserve them from decay. According to the remark of the celebrated Carlomb, we should always take into serious consideration old and well-known customs; but in this instance it is easy to admit the preserving effect of carbonization. Mr. James Randall,[4] Architect, states that he “oxidated several pieces of wood with nitric acid, and with fire,” and these processes were attended with success. Nearly the last sentence in his work is, “_oxidation only_ can be relied on, in all cases, as an effectual cure.” In charring, the surface of the timber is subjected to a considerable heat, the primary effect of which is to exhaust the sap of the epidermis, and to dry up the fermenting principles. Here this is done by long exposure to the air; and, in the second place, below the outside layer completely carbonized, a scorched surface is found, that is to say, partly distilled and impregnated with the products of that distillation, which is creosoted; the antiseptic properties of which are well known. When Mr. Binmer was examined before the Commissioners of Woods, Forests, &c., in 1792, he stated “that all steamed plank should be afterwards dried and _burnt_ to extract the moisture.” To a spontaneous carbonization must be attributed also the unchangeableness of that timber entirely black, which is met with everywhere in digging up the ground, where it has laid buried for ages. In the neighbourhood of St. Malo, France, these specimens are very common, and there most of the espaliers and vine props are made of wood, black as ebony, and famous for its durability. They have been cut from the trees of an old forest, submerged in the eighth century by an inroad of the sea, which formerly crossed a Roman road, leading from Brittany to Cotentin. Not long after the beginning of the eighteenth century, the method of heating or charring timber, before it was worked up, and also that of stoving--that is, of heating in kilns with sand--were practised in the Royal dockyards. The ‘Royal William,’ one of the most remarkable instances of durability that the British Navy has supplied, was built either wholly or in part of timber that had been charred. It was launched in 1719; never repaired until 1757; and then, when surveyed afloat, in 1785, it appeared that the thick stuff and plank had been _burnt_ instead of being _kilned_; and that the ends of the beams, the faying parts of the breast-hooks, crutches, resters, knees, &c., had been gouged in a manner then practised, which was called _snail-creeping_; by means of which the air was conveyed to the different parts of the ship.[5]