53 
Part V.] Sweet: On Air Seasoning of Indian Timbers. 
in February, 1921, at which time the humidity was about normal. 
The moisture content of the thoroughly air-seasoned ^ pieces was 
probably below the mean of wet and dry season conditions. As in 
previous cases, the moisture content of 1" boards which had been con- 
verted from green logs and stacked in open piles for a period of 24 
months is taken as the standard of dryness for the region and season. 
Taking 13'5 ( 4 - 1'5) per cent, as the moisture content in February 
of thoroughly air-seasoned boards 1" thick, it will be noted in examin- 
ing the figures for this Division in Appendix I that each of the methods 
as summarised below has produced thoroughly air-seasoned wood in 
the dimensions specified; 
(1) 15 months in the log after felling followed by conversion and 
stacking for nine months. 
Litsaea polyantha and Stereospermum chelonoides in boards up to 
1|" in thickness at least, and 3" x4" scantlings. 
(2) Conversion one month after felling, and stacking for 24 months. 
The above two species in boards up to in thickness at least, 
and 4" x 4'' scantlings. 
(3) Immersion in water for four months after green conversion 
and followed by stacking for 20 months. 
The above two species in boards up to 2" in thickness at least, 
and 4" x4" scantlings. 
(4) Girdling for 14 months, two months in log after felling, con- 
version followed by stacking for seven months. 
The above two species in boards up to 1|" in thickness at least. 
These deductions establish fairly definitely the maximum time 
required to air-season these species in the specified dimensions. As to 
how much less time would suffice only an opinion may be given at the 
present time. It is probable that both Litsaea polyantha and Stereo- 
spermuni chelonoides can be thoroughly air-seasoned in pieces up to 
two inches in thickness, following conversion from green logs, in one 
complete dry season. Scantlings up to A" x A" of Litsaea polyantha 
can probably be air-seasoned in the same length of time, and 1" 
boards in from 3 — 5 months. 
However, the actual moisture content of the converted timber 
should be the real criterion when determining whether any given lot 
of timber is sufficiently seasoned for use. 
Timber 1'^ thick and thicker which tests 13’5 (+1’5) per cent, or 
less, between the end of the rainy season and the middle of the dry 
season may be considered thoroughly seasoned for this locality. 
Thoroughly air-seasoned thin boards, such as tea box shocks, may 
[ 199 I] 
