374 
Philippine Journal of Science 
1919 
With the control, blocks injected with pure Niizu neutral oil, 
the results shown in Table XXXII were obtained. 
Table XXXII . — Japanese pine blocks injected with pure Niizu neutral oil. 
Total blocks 4 
Damaged: 
Number 2 
Per cent 50 
Dry rot: 
Number 2 
Per cent 50 
Notwithstanding the fact that Japanese pine is most liable 
to the attack of termites, the blocks treated with the neutral 
oil remained unattached after the lapse of more than two years. 
As the controls were attacked by the termite and fungus as 
well, it is clear that the green oil is an essential factor in 
preventing the damage. The mixture of Niizu neutral oil and 
the green oil (10 per cent solution) costs about 5 cents per 
gallon. Its color is pale yellow, and it gives no stain to timbers ; 
its odor is pleasant, being similar to the characteristic fragrance 
of camphor ; it is nonpoisonous to human beings ; it is not volatile 
under ordinary temperature. Thus, this solution seems satis- 
factory as a preventive against the attack of termites. 
Volatility of camphor green oil . — Twenty grams of camphor 
green oil were weighed in an absorbing vessel with special 
glass tube. The vessel was connected to a gasometer that was 
joined to a water pump. Air was pumped into the absorbing 
vessel and from time to time the amount of the oil was measured. 
The experiment was carried on for twenty-eight days (at 22° 
to 28° C.). 
Table XXXIII. — Showing volatility of camphor green oil. 
Volume of air. 
Decreased amount 
of the oil. 
Liters. 
Per cent. 
250 
4.11 
500 
5.37 
750 
5.90 
1,000 
6.08 
iturated with 1,000 cubic centimeters 
of the air, the loss 
of the green oil was estimated to be 6 per cent of the original 
volume. It is probable, therefore, that the green oil will remain 
almost permanently, even when used in the open air. 
