144 THE BOOK OF FORESTRY 
system for in spite of the first cost it is very economical 
in the long run. 
Manufacture of Cooperage.—Along certain lines man’s 
ingenuity has made it possible to substitute other 
materials for wood. Houses, bridges and telephoné 
poles are being made of steel and concrete but no 
material has yet been found that will take the place 
of wood for making vessels containing valuable liquids. 
Wood is cheap, easily worked and desirable since the 
best woods impart no taste to valuable products like 
wines or salt meats. 
No American species has had the popularity which 
the white oak enjoys in the cooperage industry and 
from the Appalachian forests large quantities of staves 
have been produced which were used by the wine- 
growers and distillers of this country. For the so-called 
“tight cooperage,” white oak stands nearly alone 
although of late years cypress has replaced it to a 
very small extent. To be used for tight cooperage a 
wood must be absolutely impervious. Even red oak can- 
not be used for tight barrels advantageously because 
its open pores permit of slight leakage in contrast to 
white oak which is watertight. 
For making lime, fruit, and flour barrels the require- 
ments are not so strict and many kinds of lumber may 
be used. Elm, red oak, ash, beech and maple are all 
used to make staves of this kind. 
While the manufacture of staves for tight cooperage 
is generally a business in itself, slack cooperage may 
be turned out as a by-product from the waste of a 
regular lumbering operation. 
Wood Distillation—The manufacture of alcohol and 
acids from wood is an industry of growing importance 
in this country. Already many plants have sprung up 
