Part V.] Sweet: On Air Seasoning of Indian Timbers. 
55 
due entirely to the difference in the rate of response to the fluctuating 
atmospheric conditions of the region. 
(vi) Cox’s Bazar Division, Bengal. 
The moisture determinations of the seasoned timber in the Cox’s 
Bazar Division were made in June, 1921, when the humidity was 
normal. The calculations were based on a total of 26 determinations 
upon three species. It is probable that in this Division the timber in 
June was in a state of maximum dryness. The seasonal variation in 
moisture content in this region is considerably less than in most parts 
of India, due to the uniformly high atmospheric moisture conditions 
throughout the year. Practically all the tests were taken on 4" x B" 
and 4" x 4'' scantlings, and there is no certainty that such thick pieces 
were thoroughly air-seasoned. However, the moisture content of the 
scantlings was so uniform in different tests and actually averaged the 
same as the 1" boards, of Dichopsis pohjantha, which had been openly 
stacked for 28 months, that there is considerable justification in con- 
cluding that both 1" boards and 4" x 4" scantlings were in equilibrium 
with the atmosphere at 15’2 ( + 1'5) per cent. 
The records in Appendix I for this region indicate that seasoning 
in the log for 17 months followed by conversion and stacking for one 
year was sufficient to accomplish thorough air-seasoning of 4" x 3" and 
4" X 4" scantlings of Eugenia operculata and Dichopsis polyantlia but 
not Drimycarpus raceniosus. Green conversion followed by open 
stacking for 28 months was sufficient for the thorough air-seasoning 
of 4" X B" scantlings of each species. * 
The experiments in this Division do not justify any conclusions as 
to how much less time is required for thorough air-seasoning. 
The moisture content of seasoned timber at the time of maximum 
normal atmospheric humidity is approximately 22 per cent. 
(vii) Sambalpur Division, Bih.\r and Orissa. 
The data available concerning the moisture content of seasoned 
timber in this Division are based on two species and 38 moisture 
determinations. The tests were made in March, 1921 at which time 
the moisture content of the thoroughly seasoned pieces was probably 
well below the mean of wet and dry season conditions. Basing the 
calculations on the pieces of each species which were known to be 
absolutely air-seasoned, i.e., upon 1" boards converted from logs which 
had been allowed to season for three months prior to conversion, and 
stacked in open piles for 25 months, the average moisture content 
was 7’0 per cent. 
Using 7'0 (•+ 1’5) per cent, as the moisture content in March of 
thoroughly air-seasoned boards 1" thick it will be observed from 
Appendix I that each of the methods as summarized below has 
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