Part I."] Pearson : Antixrptic treatment of Sleepers. 
9 
PART II. Record of Durability Tests on Treated Sleepers. 
The main object of this note is to record the results of sleepers treated 
by different processes and laid in the line to carry ont durability tests. 
The experiments were started in 1909 and the first sleepers were laid 
down in 1911. In 1912 a preliminary note * was compiled on the subject, 
and in Chapter IV is outlined the scheme according to which it was 
proposed to carry on the experiments. In 1918 a further note f was 
published, detailing the various methods of treatment and recording to 
date the condition of the sleepers laid in the open lines. 
(1) Details of experiments. 
In Appendices I to VI of this note are recorded the latest reports on 
the condition of the sleepers. It is not here necessary to review in 
detail the method and cost of treatment, as that information is recorded 
in previous reports. It is only necessary to consider the latest results 
available. The five species selected for durability tests were Pinus 
longifolia (Chir), Pinus excelsa (Kail), Dipteroeatyus tuherculatus (In), 
Diptcrocarpus alatus (Kanyin) and Terminalia tomentosa (Sain). The 
sleepers were laid in lines running through every condition of climate 
from excessively dry and hot to moist warm localities and were subjected 
to all types of traffic and conditions of metalling. The sleepers were 
treated according to four different methods, and the preservative intro- 
duced either in open tank or under pressure. An extension to the 
original scheme of experiments was carried out by treating a variety of 
Assam timbers in pressure and open tanks. 
(2) Results with Powellized Sleepers. 
(For details of durability see Appendix I and for details of treatment see Forest Records, 
Vol. VI, Part IV, pp. 21 to 34.) 
The sleepers have now been 9 to 10 years in the lines, and it should 
be noted that they were not in any way selected before treatment, 
otherwise the results might have been even better than is now the case 
* Indian Forest Records, Volume III, Part II. Note on the Antiseptic Treatment of 
Timbers in India, with special reference to Railway sleepers. March 1912. 
t Indian Forest Records, Volume VI, Part IV. A Further note on the Antiseptic 
Treatment of Timber recording results obtained from past experiments. 1918. 
C 9 ] 
