Tart IV.] R. S. Pearson: Antiseptic Treatment of Timber. 45 
v) General conclusions based on the results of experiments 
with sleepers treated with Avenarius Carbolineum oil. 
It is not possible to judge from the results obtained as to tbe value 
•of this oil for preserving sleepers, as the oldest experiments have only 
been in progress 3^ years. The results to date are quite favourable, 
especially with the Pine sleepers, the timber of which, in an untreated state, 
is more perishable than that of the Dipterocarps and Terminalia tomen- 
tosa. Whether the small amount of oil put into these sleepers is suffi¬ 
cient to protect them for a reasonable period of time is somewhat doubt¬ 
ful. At the time these experiments were carried out, every attempt 
was made to keep the cost of treatment as low as possible, though it 
would probably have been advisable to raise the cost of treatment by 
allowing a greater absorption of oil or to have reduced the cost of the 
solution by adding a cheaper grade of oil and thus making it possible 
to introduce more oil into the timber, without unduly raising the cost 
of treatment. 
In any case, these experiments will be of considerable value, as several 
of the more recent experiments have been carried out with far larger 
quantities of good grade creosote oils, which should yield valuable 
results as to the relative merits of light and heavy impregnation. 
8 Field Experiments carried out with Chloride of Zinc and 
either Green oil or Avenarius Carbolineum and a few 
sleepers treated with Atlas solution and Green oil. 
(i) Arrangements made to carry out the experiments and the 
NUMBER OF SLEEPERS TREATED. 
The arrangements made for treating these sleepers were the same as 
in the case of the sleepers treated with Avenarius Carbolineum oil, with 
the exception that the Terminalia tomentosa sleepers were obtained from 
the Betul Division of the Berar Circle, Central Provinces, instead of 
from the Kanara Division in Bombay. 
The number of treated sleepers actually handed over to the Railways 
amounted to 100 P. longifolia and 100 P. excelsa broad gauge 
sleepers, treated at Jagadhri, North-Western Railway ; 438 Dipterocarpus 
tuberculatus and 437 D. alatus, metre-gauge sleepers, treated at 
Pyinmana, Burma Railways * and 293 Terminalia tomentosa broad 
gauge sleepers, treated at Shahpur, Betul District, Central Provinces. 
These sleepers, amounting to 1,368 in all, were treated by the writer 
during the touring season of 1912-13. 
[ 175 1 
