22 
Indian Forest Records. 
[Vol. vii. 
Conclusions arrived at from Hardness tests. 
(1) Generally speaking, timber presents a harder surface on the 
cross than on the radial or tangential sections, except in the 
case of some very hard timbers. From the tests carried out 
on Sal it will be seen that the radial and tangential surfaces 
are harder than that of the cross section, and therefore this 
timber is one of the exceptions to the rule. 
As compared with other timbers, taking the average of Shorea 
robusta as 1,800 lbs. on the radial or tangential surfaces, 
Shorea obtusa is 3,000 lbs. and Shorea assamica 1,450 lbs. 
Teak is 1,200 to 1,400 lbs. according to locality in which it 
is grown. Sal should therefore be classed as a hard timber, 
if teak is classed as moderately hard and Shorea obtusa 
as very hard timber. 
(2) There is little difference between Hill and Plains-grown Sal 
from the Central Provinces, though a marked difference in 
that from United Provinces, where Hill-grown timber is 
considerably ^harder than that from the plains. 
(3) There is no difference in timber seasoned by different methods. 
II. Seasoning Properties of Sal (Shorea robusta) Timber. 
(i) RATE OF SEASONING. —Sal timber when seasoned under shelter, 
in small pieces, dries out moderately quickly; thus, the hand specimens 
prepared to determine the specific gravity of the timber, and taken from 
logs cut in various districts of the United Provinces and Central Pro¬ 
vinces, dried out in about a year. The specimens, when first examined, 
contained varying percentages of moisture, the highest recorded being 
36-25 per cent.; within 14 months all contained less than 10 per cent., 
one being as low as 7-80 per cent. Sal timber, on the other hand, absorbs 
moisture, to a surprising extent when the atmosphere is damp, even 
when it is fairly green; thus a Sal log laid down to season on the 16th 
May 1911 with 32-45 per cent, of moisture, contained 40-60 per cent, 
on the 8th April 1914, and this owing to a heavy fall of rain a day or 
two before taking the latter reading. 
When Sal timber is seasoned in the log or in large sizes it dries out 
extremely slowly, especially when left in the open, and only slightly 
less slowly when under shelter ; in fact, unless cut into small scantlings 
or boards, it appears never to attain the dryness of most other Indian 
timbers. In proof of this statement, the following figures are given 
of moisture percentages in a few of the logs laid down to season under 
different conditions :— 
[ 141 ] 
