ABSTRACT
A critical discussion of the methods of studying the permeability of erythrocytes is contained in a recent review by Jacobs (1). In this review the procedures based upon the osmotic volume changes are considered and the unique advantages of the haemolysis method are pointed out in particular. By this method, the behaviour of enormous numbers of cells is made easily visible to the naked eye, through mere changes in the turbidity of the cell suspension. This procedure may therefore be employed as a gross statistical method. Appropriate modifications and improvements in the technique, depending on the nature of the problem, make possible fairly quantitative results. A second advantage of the method is its great delicacy. A third is that by means of certain refinements (2) it may be adapted to experiments whose total duration is only a few seconds.
