104 
Indian Forest Records. 
[Vol. VI 
point, as not only has it been found necessary to prematurely reject 
many sleepers after they have been in the line a short time, due to exces¬ 
sive cracking, but in many cases the conversion of sleepers from green 
logs has resulted in excessive splitting, resulting in rejection before 
treatment. As an example in point, it may be stated that some of the 
Dipterocarp sleepers prepared in Burma and destined for experimental 
purposes, were cut from green logs, resulting in upwards of 70 per cent, 
rejections before treatment, whereas those prepared afterwards to make 
up the deficit were cut from seasoned logs, of which not 4 per cent, had 
to be rejected. 
A further lesson in connection with the splitting of timber can be 
learnt by examining the experimental sleepers treated with different 
antiseptics, which have been laid down in the line during the last six 
years. It only requires a superficial inspection of any of these sleepers, 
and especially of those which have been for upwards of 6 years in the 
line, to see that the treatment has, in nearly every instance, protected 
the fibre from decay and that the real danger, when it exists, is due to 
excessive cracking. Some of these sleepers were very thoroughly sea¬ 
soned, others only partially so, as at the time that the experiments were 
carried out, the importance of employing only thoroughly seasoned 
timber was not fully realized. 
(b) Percentage of moisture in timber. 
This brings us to the question of the percentage of moisture in the 
timber, that is, to a definition of what is meant by “ air-dry ” timber. 
In Europe and in the temperate climate of North America, where the 
minimum percentage of humidity in the air is considerably in excess 
of the minimum in the dry zones of India and where the temperature is 
far below that of the Peninsula or of Northern India, air-dried timber 
contains anything from 15 per cent, to 30 per cent, of moisture. In 
the hot weather, in the dry zones of India, seasoned timber contains 
from 8 per cent, to 15 per cent, of moisture, according to the species. 
In the damper climates, such as exist in parts of Burma, Assam, Bengal 
and the West Coast, seasoned timber rarely contains less than 18 per 
cent, to 25 per cent, of moisture. Thus, the experimental Dipterocarpus 
pilosus sleepers, dealt with in the Digboi experiments, which were treated 
2 years after conversion, contained as much as 27 per cent, of moisture, 
for the reason that Assam possesses a damp climate. On the other 
hand, when testing timber at Dehra Dun, which has a fairly dry climate 
for 7 months of the year, with a temperature rising to 105°F. in May and 
June, no tests are carried out unless the timber contains under 15 per 
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