280 A CHEMICO-PHYSIOLOGICAL STUDY OF 



marized as follows : The primary products of digestion (pro- 

 teoses), when introduced directly into the circulation of dogs 

 in doses from three to five decigrams per kilogram of body- 

 weight, produce a rapid and marked fall of arterial blood- 

 pressure, which slowly returns to the normal. If after the 

 injection of the proteoses blood be withdrawn from an artery, 

 it fails to clot as rapidly as under normal conditions, or may 

 even remain liquid indefinitely. The intensity of the effects 

 produced depends in part on the rapidity with which the 

 substance is introduced into the circulation and to a lesser 

 degree on the quantity of material employed. Further, when 

 the effects of an injection have disappeared, a second similar 

 injection may fail to produce the characteristic action, a certain 

 degree of immunity having been established. Coincident with 

 these results there usually occurs a very marked increase in 

 the flow of lymph in the thoracic duct, together with a de- 

 creased coagulability of this fluid. Other changes in the urin- 

 ary secretion and respiration are less constant, and have been 

 less thoroughly investigated. 



These statements will, we believe, receive general accept- 

 ance, as expressing well-established truths. There remain, 

 however, a large number of problems to the solution of some 

 of which the experimental work of this paper is directed. 

 Thus the questions arise: Are the various physiological re- 

 sults fall of arterial pressure, loss of blood coagulability, 

 lymphagogic influence, etc. genetically related or inde- 

 pendent phenomena ? Is the influence exercised directly upon 

 the blood or indirectly through specific organs or tissues? 

 Are all organisms equally susceptible to these actions ? Are 

 the effects produced common to all decomposition or cleavage 

 products of proteids ? What light do the phenomena throw 

 upon normal or abnormal processes in the body ? 



Such are some of the problems presented. Recent work by 

 a number of investigators, however, has thrown light in many 

 directions and revealed a multitude of facts which promise 

 advance in this particular field. Still, few investigators have 

 attempted to use for study more characteristic or more definite 



