This work is part of a more general study of interactions between montmorillonite and organic substances, carried out in connection with the fundamental results of MacEwan and Mackenzie. The object of this work was the study of adsorption of acetone in the vapor phase.

Samples of sodium and calcium montmorillonites were placed in pyrex tubes provided each with a ground glass stopper and a tap. Each tube was joined to a vacuum pump through a desiccating column and heated for several hours to 280°C so as to desorb the water contained in the clay and on the glass walls. At the conclusion of the evacuation, the tube was opened while hot, so as to introduce a recipient containing acetone in solution in castor oil (which had been previously degassed in vacuum). The tube was again closed, re-evacuated, cooled, then isolated from the vacuum pump and put into a thermostat (40°C).