Character of Wood
More than fifty varieties of wood and 400,000,000 feet of lumber are used
in this country each year in making articles of wooden ware and novelties, a
very large number of which are sold in this department.
The choice of the wood to be used depends on the purpose for which the article
is intended. Some articles must be light, others stiff, others strong, others
tough, others hard. The physical properties of wood vary with the species, the
rate of growth, the locality, and the method of seasoning. Each one of these
considerations has some definite effect on the final character of the wood.
The characteristics which must be considered are:
Hardness, Stiffness, Strength, Shrinkage, Toughness, Weight, Hardness.
Hardness is a wood's resistance to wear. This is an important quality, and
one most necessary for a
large number of household utensils. Chopping bowls and bread and meat boards
must resist severe cutting blows; rolling pins must be hard.
The hard woods are oak, beech, birch, maple, walnut, ash, hickory, all of
which belong to the broad leaf variety of trees. The soft woods are pine, spruce,
hemlock, cedar, cypress, which belong to the "coniferous" or cone-bearing
family. The hard woods are on an average two or three times as hard as the others,
but some of the so-called hard woods are really quite soft, and vice versa.
The softer a wood is the easier it is to work, and therefore when there is
no particular advantage to be gained by using a hard wood, a soft one is often
substituted. For example, ironing boards, tubs, and other implements are often
of soft woods, which are nevertheless hard enough for the purpose.
Strength
By strength is meant the ability of the wood to resist crushing, or pulling
or breaking apart. This is another very important characteristic in selecting
wood for such purposes as kitchen chairs. In general, hard woods are stronger
than soft.
Toughness
By toughness is meant a wood's ability to bend without breaking. This characteristic
is known as
resiliency, a most useful property, and especially desirable in handles.
The hard woods are about three times as tough as the soft. Among the hard
woods the hickory is the toughest. This is the reason why hickory supplies the
wood for more than two-fifths of all handles made. (See "Hickory", below.)
Among the soft woods pine is the toughest, and the alpine fir the least tough.
Stiffness
This characteristic is the resistance which a stick offers to a force which
tends to change its shape.
Soft woods, in comparison with their weight, are stiffer than hard.
|