190 
bui^letin of the bureau of fisheries. 
fO 
e 
4 
\j 
f 
'/w 
it 
r 
w 
.t/d 
S’ 
I'd' 
y' 
c\ 
30 ‘ 
SO 
70 ^ 
90 '^ 
fluidity curve does not have 
the same slope as those of 
the other oils, and also its 
fish-oil mixtures do not give 
additive fluidities. The 
data in table iv show that 
it changes in composition 
on being heated to 90° since 
its viscosity at 35° changes 
from 1.589 to 1.946. The 
values for the other oils re- 
main constant. 
It is interesting to note 
how much more viscous is 
the China -wood oil than 
the other three oils, this 
property being a good 
test of its purity, since a 
little adulteration by 
other oils of viscosity ap- 
proximating the others 
would lower the viscosity 
of the China-wood oil 
markedly. 
The viscosity curves of 
the mixtures are given for 
30° in figure i. As has 
been shown before, the 
linear curves obtained for 
soya-bean oil and linseed 
oil mixtures were to be ex- 
pected, since the viscosities 
of the components are 
nearly identical. Neither 
the viscosity nor the fluid- 
ity curves for the China- 
wood oil mixtures are 
linear. 
Fig. 2. — Fluidity curves, 3o°-9o°. 
