88 
Indian Forest Records. 
[Vol. VI 
timber treated green has not nearly so long a life as that 
treated when in an air-dry state. 
(/) That the absorption by timber when using a mixture of creosote- 
and Earth oil or Earth oil only, is practically the same. See 
Experiments III and IV carried out with the same wood, 
under similar conditions and with the above two oils. 
(g) That oil can be recovered in considerable quantities from the 
timber after it has been forced in under pressure by applying 
a vacuum (see Experiment VII). This experiment was an 
extremely^ interesting one : it was carried out with air-dried 
Hollong sleepers and the conditions of treatment were 
identical with those employed in Experiment I, except that 
a vacuum of 22-5 inches was applied for J hour, after the 
pressure had been released (see Experiment VII). In Experi¬ 
ment I, the sleepers took up 19-56 lbs. each, and in Experiment 
VII they took up 12-7 lbs. each, and it is reasonable to suppose 
that those in Experiment VII had taken up the same amount 
of oil as those in Experiment I before the final vacuum was 
applied. The actual difference in the amount of oil absorbed 
in these two sets of sleepers amounts to 6-86 lbs. per sleeper, 
while the amount of oil recovered in Experiment VII was 
42 lbs. from 7 sleepers, or 6 lbs. per sleeper, and as two of the 
sleepers were green, and therefore gave off slightly less oil, 
the figure tallies remarkably well. The procedure followed 
in Experiment VII is that known as the “ Open Cell ” process, 
by which the fibre is first thoroughly saturated throughout 
with oil and the surplus oil removed by vacuum. This 
process differs from the “ Raping 55 process, which is also- 
an “ Open Cell ” method of treatment, in that the surplus 
oil in the former process is sucked out by vacuum, while 
in the latter it is expelled by a cushion of air introduced 
before the oil is forced into the timber. It is unfortunate 
that no records are available in India as to the relative value 
of the “ Open Cell ” and common or “ Full Cell ” process- 
of treatment, as the only country in which the “ Rfiping ,y 
process has been employed for any length of time is Germany, 
from which country, at the present time, no information is 
available. The “ Open Cell ” process has much to recom¬ 
mend it, especially in India where economy in oil is of para¬ 
mount importance. The sleepers have been recently placed 
in the line near Moriani Station, and are being kept under: 
observation. 
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