"FiNLAY.—AÀ Chemical Investigation of Pintsch Oil. 447 
through all the absorption-solutions and finally collected in the storing- 
cylinder was very small in amount, and consisted mostly of air driven out 
of the apparatus, indicating that paraffins or other saturated constituents 
gave a 60 per cent. fraction which apparently did not gum after standing 
for some months, but which still made a poor motor-fuel (as tried in a 
motor-cycle). The best effects were obtained with equal parts of petrol 
and Pintsch oil, but extensive trials are needed in this direction. 
The effect of various catalysts and other reagents in reducing the 
unsaturation (and therefore, presumably, the gumming, &c.) was tried, but 
with discouraging results: boiling under reflux condenser with alcoholic 
sulphuric acid, and subjecting to the catalytic action of freshly reduced 
iron and ni various temperatures up to e C., producing little 
ced. 
Since benzene forms the largest constituent of the oil, it was thought 
that immersion of the oil in a freezing mixture might induce separation of 
d 
duced while the temperature was —20° C.; in fact, the crystals readily 
dissolved up. If the oil is previously treated with concentrated sulphuric 
acid to absorb the unsaturated constituents, fractions in the neighbourhood 
of 80° C. readily yield solid benzene on freezing, but there is apparently 
no hope of obtaining it easily from the original oil. 
In conclusion, the writer wishes to thank Dr. Inglis for his help and 
advice during the investigation. 
