Part II.] Pearson: Antiseptic Treatment of Timber. 55 
230°C. and over and has the high density of 1*128. Its viscosity at 17°C. 
as compared with water is 10, while it contains 10‘6 per cent, per volume 
of oils distilling between 230°C. and 270°C., and 12’2 per cent, of oils 
coming over between 270°C. and 300°C., the residue being a thick lim¬ 
pid, red-brown mass. 
Description of the Process. 
The Company in their prospectus state that the solution may either 
be applied with a wire brush after heating to 65 P C. to 94 P C. or that the 
timber may be soaked in a warm solution. In the first case two or even 
three coats of the fluid should be given to the timber, the solution being 
allowed to dry before the second and third coats are applied. If treated 
by the Open Tank method, the solution should be heated to S0 p C., or 
better to 95 P C., and the timber be allowed to remain in the solution for 
5 to 15 minutes according to the size, quality and character of the timber 
to be impregnated. 
iNecessary plant required for the impregnation of sleepers by the Open Tank process. 
Discussion as to the Best Methods of Treating Timber with 
Carbolineum Oils. 
From experiments carried out by Monsieur Henry, he found that the 
amount of absorption by oak and beech after being immersed in the 
solution for 10 minutes at 60°C., was not materially increased by allowing 
the timber to remain in the solution double that period. He also 
ascertained that raising the temperature to 80° C. and over in no way 
affected the amount of absorption 
( 128 v) 
