20 
Indian Forest Records. 
[Vol. VI 
was known at the time about the treatment of Indian timbers ; while 
the scale on which the experiments were to be carried out did not justify 
the erection of three expensive Pressure plants, one in the Punjab, another 
in the Central Provinces and a third in Burma. Since then the results 
of these experiments have proved the possibilities of treated sleepers in 
India, so that further experiments have been carried out in pressure 
plants. 
5. Brief description of the Antiseptics employed. 
( l ) POWELLIZING. 
Powellizing consists in immersing the timber in a Saccharine solution 
containing small quantities of arsenic, gradually heated up to a fairly 
high temperature, the time of immersion depending on the density and 
size of the timber to be treated. After removal the timber is placed in 
a drying chamber until it is thoroughly dry. It is virtually an Open 
Tank process, as no pressure is applied during treatment. No reliable 
information was available at the time the experiments were started 
as to the merits of this process, except somewhat meagre records from 
Australia and those obtained from laboratory experiments carried out 
at Dehra Dun. The cost of treatment is relatively high, though not 
prohibitive. 
(it) Avenarius Carbolineum. 
Avenarius Carbolineum oil is a Coal-tar creosote, some of the constitu¬ 
ents of which have high boiling points. It was produced in France 
and Germany, where its use has been demonstrated for treatment in 
Open Tanks. It has given satisfactory results in the laboratory experi¬ 
ments, while the results obtained with this oil by Professor Henry of the 
National Forest School at Nancy, are most encouraging. It could only be 
procured in India before the war at the high price of 2 rupees per gallon, 
which precludes more than 5 lbs. to 7 lbs. of the oil being introduced into 
a B. G. sleeper. It remains to be seen whether this very limited 
amount of oil is sufficient to preserve the timber from decay for a reason¬ 
able time : the laboratory results certainly indicate that this is the case. 
( in ) Chloride of Zinc and Green oil. 
Treating timber by a mixed impregnation method is a somewhat 
speculative experiment. Its chief aim is to reduce the cost of treatment. 
Chloride of Zinc alone is a well-known antiseptic in connection with the 
treatment of timber, the use of which has been discussed in the previous 
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