. . "thylene glycols, cellulose derivatives such as methylcellulose, hydroxypropyl-methylcellulose and ethylcellulose, polyvinyl alcohol, proteins such as gelatin, salts such as alkali or alkaline earth metal sulfates, alkali or alkaline earth metal chlorides and alkali or alkaline earth metal carbonates, for example sodium sulfate, magnesium sulfate, calcium sulfate, sodium chloride, magnesium chlorid" . . . . . . .