In a recent paper Gamble and Ross (1) have demonstrated that, in the presence of pyloric obstruction in the dog, there occurs a loss in vomited gastric secretions of sodium as well as of chloride ion and water. They have shown the relationship of this loss of base to changes in the chemical structure of blood plasma and its significance from the point of view of the reparative action of injections of NaCl solution.

In this paper are presented measurements of the amounts of water, fixed base and chloride found in the stomachs of rabbits following experimental obstruction of the pylorus. These measurementswere obtained with the purpose of determining quantitatively the extent of the loss into the stomach of each of these important components of the body fluids during the survival period followingpyloric obstruction. Rabbits were used for the reason that in these animals the vomiting reflex is absent. Their stomachs will therefore conveniently collect for measurement substances leaving the body in the gastric secretions and contamination of this material by urine or feces is dependably avoided. It was found, however, that the collection period following obstruction could not be begun with an empty stomach. More than a week of fasting is required to completely empty a rabbit's stomach. The usual content is of a stiff texture and attempts to either wash it out or remove it surgically without considerably traumatizing the stomach were unsuccessful. The plan used in estimating