21. On the Diuretic Action of Certain Haemolytics, and the Action of Calcium in Suppressing Haemoglobinuria. (A preliminary communication.) _Ibid._, 1905. 22. The Diuretic Action of Certain Haemolytics and the Influence of Calcium and Magnesium in Suppressing the Haemolysis. (Second communication.) _Ibid._, 1905. 23. The Action of Pilocarpine and Atropin on the Flow of Urine, by John Bruce MacCallum. _Ibid._ 24. Factors Influencing Secretion. The Journal of Biological Chemistry, Vol. I, 1906. AUTHOR’S PREFACE. The following pages contain an account of a long series of experiments made to determine the action of saline purgatives. Many of the results have been separately published in various scientific journals, and they are now gathered together with certain new material in an attempt to give as connected and complete an account as possible of the action of this class of drugs. The experiments were begun at the suggestion of Professor Loeb, to whom I am greatly indebted for the constant interest which he has taken in the work, and whom it is a pleasure to thank for many helpful suggestions. CONTENTS. PAGE Chapter I.--Normal Movements and Secretion of the Intestine 1 Chapter II.--The Subcutaneous and Intravenous Injection of Saline Purgatives 9 Chapter III.--The Local Application of Saline Solutions to the Peritoneal Surfaces of the Intestine 23 Chapter IV.--The Production of Increased Secretion of Fluid into the Intestine by the Saline Purgatives 29 Chapter V.--The Inhibiting Action of Calcium and Magnesium on the Movements and Secretion of the Intestine 38 Chapter VI.--The Action of Saline Solutions on Loops of Intestine Removed from the Body 50 Chapter VII.--The Action on the Intestine of Solutions Containing Two Salts 57 Chapter VIII.--The Effect on the Intestine of Intravenous Saline Infusions 65 Chapter IX.--Mode of Action of the Saline Cathartics 74 Chapter X.--Possible Therapeutic Value of These Experiments 83 Chapter XI.--The Action of Purgatives of Vegetable Origin 86 CHAPTER I. Normal Movements and Secretion of the Intestine. A. _Normal Movements of the Intestine._