Show TRUST RESPONSIBLE BRANDS OF GREASE GREASEL L i Testing oils or 01 greases must generally be left by the motor car owner to the manufacturer of the lubricant and the best guaranty of Is a a. branded product produced by a responsible c concern con con- m- m cern Of course acid even en a trace o of it it is about the last thing to be desired in a lubricant and the following Is a simpIe simple simple sim sim- pIe test that may be employed by the car owner if it It becomes necessary for him to try tryout out the lubricant he is using Take a piece of sheet copper and after thoroughly cleaning it smear on it some of the lubricant that Is under suspicion allowing It to stand for about two weeks If Ir there is any acid present it will wll deposit deposit de de- he- he posit on the copper in the form of agreen a agreen agreen green stain |