10 Indian Forest Records. . [Vol. Ill 
process should be made into a concentrated solution, i.e ., 3‘5 per cent, of 
each mixed with water and applied cold, the immersion of the timber last¬ 
ing for 8 days. If a pneumatic plant is used a half strength solution can 
be employed. When utilizing the above salts great care should be taken 
that they are not adulterated with Na 2 SiF 6 , for such admixture renders 
the solution valueless. 
Of the Dinitro substances may be mentioned (a) Bellitol, which 
is a ^ per cent, solution of Dinitro-benzol and mineral oil, (b) Bellit, 
which is made up at various strength and known as Bellit-Einfach and 
Bellit Doppel-fluor, being always a compound of sodium fluoride 
(Na, F.80 per cent.) and an organic salt of Dinitro-phenol or anilin 
Dinitro-phenol. These are cheap substances ; in fact mineral oil is 
cheaper than Creosote and Bellitol is cheaper than either of these oils. 
Another great advantage is that Bellit and Bellitol are obtainable 
in the powdered form, so that only the concentrated solid ingredient 
of the solution has to be imported, thus enormously reducing the price 
as compared with the import of liquid solutions. The Captain further 
states that in his opinion they are as good, if not better than Creosote. 
(3) POSSIBLE TIMBERS SUITABLE FOR RAILWAY SLEEPERS 
AFTER TREATMENT, OTHER THAN TEAK, 
SAL, DEODAR AND PYINKADO. 
Technical Character of Timber Suitable for Sleepers. 
On page 3, sub-section “ Auxiliary Species/'’ it was stated that only 
certain timbers fulfilled the conditions necessary for sleepers. The most 
important factors are (i) that the present price of the timber together 
with the cost of treatment be less or at most not in excess of that 
of the best untreated sleeper woods, (ii) that they be procurable in large 
quantities, and (iii) that they be mechanically strong enough for the 
purpose. The first two conditions can be best determined by Forest 
Officers ; for a definite opinion on the last condition we must turn to ex¬ 
pert engineers, and to past records. Mr. Couchman in his Note of 1905 
lays down the necessary qualities required for sleepers as follows :— 
“ A timber to be suitable for railway sleepers must possess the 
following qualities :— 
(a) It must be physically hard or tough enough to resist the cut¬ 
ting action of the rail or chair on its surface, and also the 
constant grinding action produced by traffic passing over it, 
packing of the road, etc. 
( S3 ) 
