60 
The C. P. of the standard at 110 V. was taken as 16. 
The specific gravity was determined by a hydrometer and also by 
weighing on a delicate balance. 
In determining the flashing point the open-vessel method was used. 
The oil was put into a porcelain evaporating dish and slowly heated. It 
was constantly stirred with a thermometer. A small jet burning at the end 
of a glass tube was held a half inch above the surface, and the flashing 
point noted. Each sample was tested in this way four or five times. 
The table on the opposite page shows the results of the observation. 
The flashing point of safe oil should not be less than about 115° 
F. or 46° C., having a gravity of from 40° B. to 50° B. The above 
oils, in my test, all come within the safety limit except the last sample, 
whose flashing point tested 44:57 C. Of the above the White Seal and the 
Eosene are held as the best grades, the others are cheaper grades. The 
White Seal retails for 20 cents, the Eosene for 15 cents and the Headlight 
for 10 cents. Noting the flashing points of the three samples it would 
appear that the cheapest oil is the safest. The samples tested are all safe 
with the exception of the last sample, and as far as quantity and quality 
of light are concerned there is but little difference. 
