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ml seasoning of at Least six months' exposure to tUe atmosphere. Al- 
though other and improperly applied met hods of dry-heating and after- 
creosoting may render timber brittle under the pile-driver, none of the 
timber so far carbonized and wood-creosoted has proved objectionable 
from this cause. On the contary,the wood-creosote restores the tough- 
ness and. elasticity to the charred wood, so that this method has given 
great satisfaction wherever used, as, for example, at Aspinwall, Tan 
ama, under the Panama Caual Company; and at Charleston, S. 0., 
under tlu k Northeastern Railroad. Company ; in both cases under cir- 
cumstances extremely unfavorable to the life of the timber. 
After the wood has been carbonized or kiln-dried, it is loaded upon 
trucks, which, with their load, are rolled into the creosoting cylinders, 
respectively of G5, 75, and 90 feet in length, each with a diameter of 
G feet. The doors of the creosoting cylinder are then closed for from 
lour to fifteen hours, during which time the temperature within the cyl- 
inder is raised by dry heat to from 140° to 1G0° Fr., a vacuum of from 
1) to 24 inches is kept up by means of a vacuuin-puinp, and the sap, al- 
bumen, and other impurities are thus thoroughly extracted from the 
wood and pumped out of the cylinder. 
The vacuum-pump is then stopped and a force-pump put to work, by 
which the cylinder is filled with hot wood-creosote oil, under a pressure 
of from G5 to 100 pounds per square inch, this pressure being constant 
from four to eight hours, according to circumstances. By this part of 
the process from eight to twenty pounds of oil are forced into each 
cubic foot of wood. The pressure is then relaxed ; the unabsorbed oil 
is then run off into outside tanks, the doors of the cylinders opened, and 
the impregnated timber, still on its trucks, is rolled out. 
This treatment with wood-creosote oil, as above described, has been 
favorably reported upon (March 18, 188G) by a special board of United 
States Navy officers; and the wood so treated has had an extensive use 
already upon the Government wharf at Charleston, S. C, at the jetties 
at Port Eads in the M. T. and E, P. Inclined Railway at Cincinnati, 
Ohio, as well as in many other less important places and structures. 
Treatment with this oil is especially valuable to wood that is to be 
used in the construction of bath-houses, wharves, docks, quays, piers, 
railroad bridges, railroad trestles, wooden pavements, flats, lighters, 
scows, ship spars and masts, ship decks and bottoms, or used in rail- 
road cross-ties, foundation sills for houses, piazzas, porches, floors, 
fence-posts, and telegraph poles. No cases have yet been discovered 
where either rot or Teredo has attacked wood that was thoroughly im- 
pregnated with this wood-creosote oil, 
