Open main menu

Page:Popular Science Monthly Volume 15.djvu/541

This page has been validated.
525
DRY-ROT IN TIMBER.

scheme for such a party, or a theme of which the variations are endless. Seven or eight guests can thus be brought into close contact: with a larger number the party is apt to form two coteries, one on each side of the host. The number is a good one also in relation to the commissariat department—eight persons being well supplied by an entrée in one dish; while two are necessary for ten or twelve. Moreover, one bottle of wine divides well in eight; if, therefore, the host desire to give with the roast one glass of particularly fine ripe Corton or Pomard, a single bottle is equal to the supply; and so with any other choice specimen of which a single circulation is required; and of course the rule holds equally if the circuit is to be repeated.

And this leads us to the question—and an important one it is—of the wine.—Nineteenth Century.

 

DRY-ROT IN TIMBER.[1]

NEARLY everybody has heard of dry-rot, and knows that it is something which causes the destruction of wood in a manner different from ordinary decay. Some suppose the effect to be due to peculiar insects that gnaw timber to powder, and others have no very definite notions as to what produces it. Carpenters, ship-builders, lumbermen, and house-owners often find, by the rapid destruction of their property, that, whatever its cause, it is a very serious matter, and they seek to be protected from the evil, though taking little pains to inform themselves of its real nature and conditions. The subject is, however, one of curious scientific interest, and has now come to be pretty well understood. An excellent work upon it has recently been compiled by Mr. T. A. Britton, an eminent British architect, who has ransacked all sources of information; and for the materials of the statements which here follow we are indebted to this book.

To understand the nature and effects of dry-rot we must first glance briefly at the structure and properties of wood. The mass of the trunks of timber-trees consists of slender, short fibers, with tapering ends, which overlap each other; but this overlapping does not prevent the passage of sap through them. At first these fibers are hollow, but are gradually filled by the deposition of solid matter from the sap within them. The strength of wood is due to the shortness and overlapping of the fibers, and to the presence of this deposit. Woody fiber pervades the tree from the tips of the roots to the extremities of the branches, and is the chief organ of circulation. A current of sap passes upward through it, from the roots to the leaves; and another

  1. A Treatise on Dry-Rot in Timber. By Thomas Allen Britton. London and New York: E. & F. N. Spon.