354 THE CONIFERS (GYMNOSPERMS) — FORESTS 
dried is one precaution taken to insure its lasting. Other 
methods used are charring portions that are to be covered by 
earth, and a third, the most common, is the use of chemicals. 
Railroad ties, for instance, are thoroughly impregnated with 
a solution containing creosote, among other substances, by 
being soaked in it for a long time, or by having it driven in 
under pressure. This acts as an antiseptic preventing 
bacteria and fungi from growing in the wood, and pro¬ 
longing the usefulness of the timber to a remarkable degree. 
While treating ties in this way is costly at first, it is an 
Figure 328. — Young Plantation in the Adirondacks. 
economic measure on the whole, as it takes a smaller quantity 
of timber, and less labor than would be the case if the ties 
had to be replaced frequently. 
Some kinds of wood depend for their beauty on the glisten¬ 
ing medullary rays. These show to best advantage when 
cut lengthwise or obliquely, an effect obtained in quarter- 
sawn timber. 
302. Properties of Wood. — The question may arise, What 
makes wood so valuable? Is there nothing else that can be 
used in its place ? One of its most valuable properties is 
that it is so easily shaped with sharp tools. Another is that 
it is light, compared with iron and steel, at the same time 
