^2 
Indian Forest Records. 
[VoL. IX 
of treatment, as in the case of the Pines the life has been trebled as 
compared with untreated timber, and about doubled in the case of the 
Dipterocarps. On the other hand the process cannot be advocated and 
is one more suitable for fencing posts than for railway sleepers. 
(tf) Treatment with Chloride oj Zinc and small quantities of creosote to 
protect the salt. 
The third process consisted in treating the sleepers with a 2 per cent, 
solution of Chloride of Zinc and after allowing them to dry out, to dip 
them in a good grade of creosote, such as Solignum or Green Oil. This 
process like the second is one aiming at reducing the cost of treatment. 
Chloride of Zinc is about the only salt used for treating timber which has 
stood the test of time, though Fluoride Salts have of recent years come 
considerably to the front. The results are so far not encouraging, in 
fact strong indications are present to show that the sleepers which have 
been rather over seven years in the line are fast deteriorating. These 
results are corroborated by similar results obtained with this process in 
America. It was stated above that the process involved two separate 
treatments, by first treating the timber in the salt solution and then in 
oil and that the results were even then not satisfactory. A modification 
of this process has been introduced by Mr. Card, a Creosoting Engineer 
in the States, by which the salt and oil solutions are introduced simul- 
taneously as an emulsion into the timber. The durability tests on 
sleepers treated in this way have given excellent results. The writer 
inspected a large plant working according to the Card process, owned 
by the Ohio-Baltimore Eailway, which turned out over a million sleepers 
annually. It is probable that this process would do well in India, and 
at the same time keep down the cost of treatment as compared with the 
full cell Creosote process. 
{v) Treatment with a mixture oj Earth Oil and Creosote according to the 
jull cell process. 
The results of this experiment have been divided into two parts, 
namely, sleepers treated in open tanks and those treated under pressure. 
The sleepers have only been in the line from 5 to 6 years and faherefore 
to compare their condition with those treated by other processes and 
which have been in the line for anything from 7 to 10 years is not possible. 
So far the sleepers treated in either open tanks or under pressure are 
doing uniformly well. They have been laid down under many varying 
conditions of climate, some being in the dry zone of the Central Provinces, 
others in Burma, many in Assam and others again in the Punjab. The 
process by which these sleepers were treated varies little from the full 
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