80 ■ KANSAS CITY REVIEW OF SCIENCE. 
CHEMISTRY. 
THE PRESERVATION OF WOOD FROM DECAY. 
PROFESSOR F, W. CLARKE. 
\Read before the American Forestry Congress^ April^ 1882.'] 
That the protection of wood from decay is one of the most important of indus^ 
trial problems can hardly be denied ; and yet in this country it has scarcely begun 
to receive proper attention. Our forests are rapidly wasting away, the price of 
wood is continually increasing, its applications are becoming more and more 
numerous, and still Httle is done. In 1855 lumber sold for about $18 per thou- 
sand, in i860 for $24, and in 1865 for $45. Although a single acre of pine land 
yields on the average only about six thousand feet of timber, billions of feet are 
annually sold in the United States. It is estimated that the supply of white pine 
will be exhausted, at present rates, in about eight years. The question of pre-- 
servatives will force itself upon our notice so urgently that it cannot be ignored. 
Prudence already insists upon a more rigid economy. 
In Europe, much attention hats been paid to the problem — England, France, 
and Germany taking the lead. In Great Britain alone not less than fifty patents 
for the preservation of wood have been taken out during the present century. 
To be sure, some patents have been granted at Washington, also, but their 
value is relatively slight. What is the consequence of this trans-atlantic 
superiority? Simply that railway sleepers, bridge timbers, and telegraph posts 
last more than twice as long abroad as in America, and that all other exposed 
wood has similarly gained in durability. Surely this fact is worth the attention of 
our practical men. Mere temporary cheapness cannot much longer pass for 
economy. 
Many experiments demonstrate the advantage of protecting wood by chemi- 
cal means. Prepared and unprepared timbers have been exposed together, and 
the overwhelming superiority of the former proved. A great variety of preserva- 
tive methods have been found practicable, but an attempt to decide upon their 
relative merits is quite difficult. The material for criticism is bulky enough, but 
deficient in quality. All the desirable details are rarely given. A process which 
thoroughly protects one kind of wood may utterly fail with another. One 
method may succeed with seasoned timber, yet be useless for preserving green 
wood. Accordingly we find the most contradictory statements concerning every 
prominent protective process. One man finds it admirable, another denounces 
it as worthless. In order to get at results of true practical value, and to avoid 
these seeming discrepancies, we have to consider several things: first, the general 
