74 
Indian Forest Records. 
[VOL. III. 
The above figures, as compared with those of Creosote extracts, show 
very high rates of absorption; on the other hand, the solution being 80 
per cent, water and 20 per cent, antiseptic, the amount of the preservative 
which has been taken up and which goes to protect the timber is by no 
means excessive. The reason of this excessive absorption is due to the 
greater penetrating power of water than oil and also to the much longer 
period of immersion, conditions which not only hold good for mixtures of 
water and “ Atlas,” but also for all antiseptics in which a salt is dis¬ 
solved in water, such as sulphate of copper, or zinc chloride. 
In the above set of experiments a solution of 20 per cent. Atlas “A” 
was used. The Home firm have since pointed out that this strength is 
excessive, as from recent observations a 10 per cent, to 15 per cent, 
solution is quite effective. They further state that in excessively damp 
localities cold tar should be applied after treating with the solution and 
that instead of hot tar being applied better results are obtained by 
applying it cold and mixed wfith about 5 per cent, kerosine. 
Plate VIII exhibits various timbers treated with a 20 per cent- 
solution of Atlas and immersed for 24 hours. Specimen a illustrates a 
treated piece of Boswellia serrata (4" x 4" X 12"), through which the 
solution has completely penetrated. Specimens b and c are of Finns 
excelsa (blue pine) and Picea At or hid a (spruce), into which the solu¬ 
tion has penetrated at the end and on one side, the other side 
when immersed was touching the bottom of the tank so that the solution 
could not circulate freely and consequently the penetration was checked 
on that face of the treated specimens. 
Specimens d, e and f are Pterocarpus macrocarpus (Burman 
Padauk), Finns longifolia (Chir) and Shorea, robusta (Sal), respectively. 
Specimens d and f are of hard woods, into which the solution has only 
penetrated one-fourth inch, but even this is considerably deeper than 
was the case when treating these species with Creosote oils, while the 
solution has in parts completely penetrated the Chir specimen e. 
Cost of Treatment. 
The following figures giving the cost of treatment are based on the 
percentages of absorption given in the above table. The cost per gallon 
of the concentrated solution comes to HI 6 per 5 gallon drum or 51*2 
annas per gallon of 16*28 lbs. weight or 0*19 annas per oz. (concentra 
ted). The solution used was 20 per cent, of concentrated “Atlas” to 80 
( 147 ) 
