[Part IV.] R. 8. Pearson: Antiseptic Treatment of Timber. 87 
the above procedure, as this timber is difficult to impregnate, 
attempts might be made to treat it by boiling in the oil under 
a 20 inches vacuum for 2 hours, at a temperature of 115°C., 
then applying a pressure of 150 lbs. for 3 hours, by doing 
so the treatment would probably be facilitated. 
(c) That Bischofia javanica, or ‘Uriam’ is very difficult to treat owing 
to its dense nature (Experiments XI and XII). The sleepers 
were obtained from the Dibru-Sadia Railway Company, but 
their exact degree of dryness when treated was not known ; 
they appeared, however, to be only partially seasoned. Be¬ 
fore definitely stating that this timber is unsuitable for treat¬ 
ment, it would be necessary to carry out further experiments 
with thoroughly seasoned timber, and to treat it in the same 
way as is advocated for Terminalia myriocarpa. 
(d) That the 4 Hollong 5 ( Dipterocarpus pilosus) and ‘ Hollock ’ 
(Terminalia myriocarpa) sleepers, which had been seasoning 
for upwards of 2 years and 8 months respectively, cannot be 
considered to be thoroughly air-dried, as the former con¬ 
tained 27-45 per cent, and the latter 29-27 per cent, of mois¬ 
ture. Taking into consideration the time during which these 
sleepers had been seasoning, it is probable that the percentage 
of moisture in the timber represents the degree of dryness 
to which the timber attains in the damp climate of Assam. 
No doubt the sleepers, on being placed in a well-drained and 
dry ballasted line, even in Assam, would dry out further, 
as a railway track at certain times of the year is as hot a 
place as can be found ; nevertheless, it is thought that the 
additional moisture which may be lost after placing such 
sleepers in the line, will not be sufficient to cause excessive 
cracking of the timber. Were the sleepers destined for one 
of the Central India, United Provinces or Punjab Railways, 
or, in other words, to be placed in a dry, hot climate, there is 
little doubt that the timber would have to be further seasoned 
before treatment, either by artificial means or by taking it to 
a dry, hot climate, and allowing it to further season before 
treatment. 
{(e) That the treatment of green timber is altogether to be dis¬ 
couraged. In the first place it is more difficult to effect, 
as will be seen by comparing Experiments I and VI, carried 
out under identical conditions with air-dry and absolutely 
green timber ; and secondly, an even more important point, 
ascertained from experience in Europe and America, the 
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