70 
Indian Forest Records. 
[Vol. VI 
15 lbs. of the salt and 4 lbs. of the oil, and 6 annas 5 pies for a Dipterocarp 
metre-gauge sleeper with 9 lbs. of the salt solution and 1 lb. of oil. With¬ 
out doubt the cost of treatment could be still further reduced, as 6 annas 
.10 pies per gallon is above the usual rate for Green oil in Europe. Or 
again, a good grade of Coal-tar creosote at 4 annas 6 pies per gallon could 
be substituted, which w~ould further reduce cost of treatment, probably 
without seriously affecting the efficiency of the process. 
The 4th and last group of experiments were carried out with a mixture 
of Solignum and Petroleum oils. The oils used were Solignum and Liquid 
Fuel ; here again costs run higher than they should have done, due to 
the high price of Solignum. However, by applying the principle of 
mixing Coal-tar products with Petroleum oils and using, for instance. 
Green oil or a good grade of creosote , as used for treating timber in 
Europe, the results obtained are very different. The mixture instead 
of costing about Re. 1-10-0 per gallon, as was the case with Solignum 
and Liquid Fuel , is reduced to 9 or 10 annas per gallon. Putting the 
maximum cost of treatment admissible at Re. 1-4-0, this will permit of 
somewhere in the neighbourhood of 18 lbs. of the solution being intro¬ 
duced per broad gauge sleeper, a larger amount than was used in any of 
the above experiments. 
The durability tests have hardly been carried far enough to justify 
definite statements being made, while the results have been discussed in 
detail elsewhere, so need not be dealt with again; sufficient is it to say 
that to date none of the sleepers have shown any serious signs of 
failure. 
PART IV. 
MISCELLANEOUS FIELD EXPERIMENTS CARRIED OUT WITH 
SLEEPERS TREATED IN OPEN TANKS. 
Several experiments in connection with the antiseptic treatment of 
timber, other than those carried out according to the scheme drawn 
up at the Forest Research Institute in 1910 and described in Part III 
of this note, have been made of recent years in India. These experi¬ 
ments were either started by Indian Railway Engineers, or at the instiga¬ 
tion of firms interested in any special process or were in the nature of 
supplementary experiments to those enumerated in Part III, and carried 
out by the Forest Department. For convenience sake, these experi¬ 
ments are arranged according to the antiseptic employed, irrespective 
of the agency of treatment. 
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