Part IV.] R. S. Pearson: Antiseptic Treatment of Timber. S 
found in the Indian forests may be divided into “ major ” and “ auxili¬ 
ary ” species. A classification based on similar lines can be evolved in 
connection with many other industries, such as cabinet work, cooperage, 
turnery, carriage work, etc., and though, by grouping all such timbers 
together and calling them “ major species ”, we obtain a fairly long list 
of timbers classified under this head, nevertheless the remaining auxili¬ 
ary species form an infinitely larger group. For sylvicultural, as well as 
for economic reasons, it is obvious that the removal of mature trees of the 
auxiliary species should keep pace with the removal of those of greater 
value, and the only profitable way of doing this is to create a demand 
for the timbers, one of which, it is fairly certain, will be in the form of 
treated sleepers. 
Persons not acquainted with the conditions of Indian Forestry 
might, with reason, wish to know why the auxiliary species should be 
chosen for experiment in connection with the treatment of sleepers,, 
as in Europe and America nearly all species of timber are treated before 
being laid down as sleepers in the line. The answer is that the forests 
of India contain at least five species, namely Teak (Tectona grandis), 
Sal (Shorea robusta), Pyinkado (Xylia dolabriformis), Deodar (Cedrus 
Deodara) and Nahor (Mesua ferrea) which, owing to their durability, 
require no treatment while, with the exception of Oak, this is not the 
case elsewhere. These five species of timber, as far as sleeper woods 
are concerned, are the “ major species ”, and though Teak is now only 
used in special cases, such as for bridges, etc., the other four species go 
to make up the greater percentage of wooden ties supplied by this coun¬ 
try. The demand, however, is far in excess of the supply and this 
necessitates the treatment of the “ auxiliary species ” to make up the 
deficit. 
The second point referred to concerns the shortage of wooden sleepers 
in India. Were all other factors to be ruled out of consideration, this 
factor alone would justify an investigation into the possibility of in¬ 
creasing the supply of sleepers by the treatment of hard-woods of in¬ 
sufficient durability. That difficulty has been experienced by the 
Railway Authorities in obtaining adequate supplies of sleepers is common 
knowledge and, as a proof of this assertion, if any is necessary, one has 
only to refer to the statements showing the imports, during recent years, 
of Australian and American sleepers into India and to remember that 
iron ties are commonly found in use on the main lines running far from 
the sleeper-producing localities. 
Another factor has to be taken into consideration in connection with 
the demand for sleepers, and that is that the Railway Systems of India 
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