The purpose of this paper is to study various factors that may influence the intraocular pressure in glaucoma and thereby obtain information concerning the etiology and pathogenesis of this disease. More specifically, this paper is concerned with the effect of ganglionic blocking agents and some central nervous system depressant drugs on aqueous humor dynamics in glaucomatous eyes. Primary glaucoma cannot be duplicated satisfactorily in the animal eye; therefore, its pathogenesis has to be investigated on human glaucomatous eyes. The tonographic method of Grant * was employed in the present work because it is a convenient research tool with which one can study the mechanism of ocular hydrodynamics in patients. The use of ganglionic blocking agents in the treatment of hypertension has been well documented in the past few years; Paton,3 Burt,4 and Locket5 described the mode of action of these agents in man, while their specific effect on