Part IV.] B*S. Pearson: Antiseptic Treatment of Timber. 31 
cracks have developed, the*screw holes have not enlarged, though the 
cut under the rail-seat is, in some cases, up to g" deep. These Powellized 
‘ In 5 sleepers may he said to he doing very well, when taking into con¬ 
sideration that the life of untreated ‘ In ’ sleepers is hardly 5 years. 
The Sal (Shorea robusta) sleepers laid in the adjoining line at the same 
time as above, do not present so good an appearance as the ‘ In ’ sleepers. 
Dipterocarpus alatus, 4 Kanyin.’—No sleepers have been removed 
during the six years they have been in the line. Their condition is 
very similar to that of the 4 In 5 sleepers, with which they are laid in the 
same line. The tendency to split in these sleepers is somewhat more 
marked than in the case of 4 In.’ The spikes are holding well, while the 
cut under the rail-seat shows, as it does in the case of the 4 In ’ sleepers, 
the necessity of using bearing-plates. The results to date of Powellized 
4 Kanyin ’ sleepers is decidedly satisfactory. 
Terminalia tomentosa or 4 Asain.’—The sleepers have been in the line 
nearly 6 years and, out of 814 laid down, 9 have been removed during 
that period. The removals have been due, in every case, to original 
faults. It is known that these sleepers were cut from old trees and tops 
left after logging, hence many of the sleepers show faults. As a matter 
of fact, this is probably the best of the five species tested for sleepers, as 
the timber is extremely hard and, though liable to develop cracks, its 
tendency to do so is not greater than that of 4 Pyinkado ’ (Xylia dolabri- 
formis), which is classed as one of the best sleeper woods of India! The 
spikes hold very firmly, the tendency to cut under the rail-seat is insigni¬ 
ficant and no bearing-plates are necessary. The results to date With 
this species are very satisfactory. 
(v) Other Experiments with Powellized sleepers in Burma, not 
INCLUDED IN THE ABOVE SCHEME. 
A record of considerable value is available from Burma, with respect 
to 100 sleepers of ten different species of timber which, after having been 
Powellized, were laid down together with an equal number of untreated 
sleepers of the same species in April 1 !908, near Pyinmana, on the Bangoon- 
Mandalay section of the Burma Bailways. Their condition is re¬ 
corded below, the information having been taken from a joint report 
submitted by Mr. A. Bodger, Forest Besearch Officer, Burma, and the 
Assistant Engineer, Yamethin, Burma Bailways, after their inspection 
of the 3rd June 1916. 
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