A novel tester for ascertaining the specific gravity of gasoline is shown in the annexed cut. This consists of three glass balls colored red, white, and blue, and arranged at different levels in the tube, which is but 3 inches high, small enough to pass through a %,-inch hole, and which requires less than 1,4 ounce of gasoline to fill it. Each ball can rise vertically about % inch. If the gasoline has a specific gravity of 60 deg. Baume, the red ball will float; if 65 deg., the white one; and if 70 deg., the blue one. The instrument weighs but 2 ounces. It is provided with a chain a foot long. The maker is the Storage Battery Supply Co., 239 E. 27th Street, New York city.