Abstract
The “oiliness index”, a measure expressing the oiliness of lubricants, proposed by the author, is represented by the volume of kerosine added to the defi-nite quantity of the sample so far as the dilution reaches to a limit where Thurston's oil-tester can no longer operate normally.The oiliness of various oils and fats was discussed from the indices: the oiliness index relates with the acid value and not with the iodine value.The variations of oiliness indices with load and revolution of the tester and with temperature were examined for castor oil and rapeseed oil as typical lubricants.Various Japanese lubricants were compared with foreign lubricants by the oiliness indices with reference to the oiliness measured by soda's four-ball system oil-tester.
