Cork-Tree, or Quercus su-ler, L. a species of oak indigenous in Spain and Portugal, where it attains the height or' from 30 to 40 feet; has a thick, rough, fungous bark, and oval serrated leaves, which are downy underneath.
The bark of this tree furnishes that useful material, cork ; which, becoming of a thick fungous nature, is separated from the trunk, while a new bark is formed under it, which, in the course of six or seven years, is sufficiently thick for barking. Nevertheless, the tree continues to vegetate, and another fresh bark grows under the former, which likewise affords cork in the same period of time.
In the Gentleman's Magazine for 1758, we met with the following curious contrivance of a cork-waist-coat, for the purpose of preventing accidents by drowning. It was invented by Mr. Dubourg, and is composed of four pieces of cork, two for the breasts, and two for the back, each being nearly of the same length and breadth as the quarters of a common waistcoat, without flaps ; the whole is covered with coarse canvas, having two holes to put the arms through.—. There are spaces left between the two back pieces and each back and breast piece, that they may the more easily be adjusted to the body. Thus, the waistcoat is open only in the front, and may be fastened on the wearer with strings ; or, if it should be thought more secure, with buckles and leather straps.
The weight of this cork-waist-t oat does not exceed twelve ounces, and may be made at a very moderate expence. It is more simple in its, form than any other contrivance for a similar purpose. Mr. Dubourg has made trial of its efficacy in the Thames, and found that it not only supported him on the wafer, but that even two men, with their utmost efforts, were not able to sink him. Hence it is eminently calculated for mariners, passengers at sea in general, and likewise for all those who resort to bathing-places for the benefit of their health ; as the most timorous and delicate person may, with perfect safety, boldly venture with one of thee waistcoats into a rough sea See Bamboo-Habit.
The expence of providing a suffi.cient number of them for the British navy, can be no objection to a nation so gratefully fond of a powerful marine establishment. - Those of our readers who are desirous of obtaining farther information on the subject of cork-waistcoats, we refer to a treatise written byMr. J. Wilkinson, and entitled The Seaman's Preservation, or Safety in Shipwreck, printed in 1759, 8vo. 1s. 6d.
Cork is applied to various uses, by different nations. The Egyptians made coffins of it, which being lined with a resinous composition, preserved dead bodies from corruption. The Spaniards burn it, to make that kind of light colour we call Spanish Hack, used by painters. They also employ it to line stone walls 5 an expedient which not only renders them much warmer, but also corrects their moisture in damp weather.
In medicine, the bark, as well as the acorn of the cork-tree, are reputed to be astringent, after being burnt, reduced to powder, and used externally. But in Britain, the former is principally employed for stopping bottles and casks, and lining the inner soles of shoes and slippers. Cups made of cork are said to be of service to hectical persons, when used as their common drinking-vessels.