“…The methods of measuring and recording the rate of oxygen consumption and the time-course of the suspension medium pH changes (pH,), used for calculating the quantity of acid equivalents translocated [+H'(acid)] , were essentially as before [3,17]. In some experiments, the quantity of Ca*' in the medium was measured at a given moment by observing the change of pHo on injecting excess EDTA, according to the principle originally introduced by Chappell, Cohn and Greville [I].…”