282 A CHEMICO-PHYSIOLOGICAL STUDY OF 



blood and thoroughly cleansed, and the blood was allowed to 

 escape for a second or two before the next portion was taken. 

 The samples of 2 c.c. each were received in graduated cylin- 

 ders with a caliber of one centimeter. The " rate of coagula- 

 tion" was taken to be the time which elapsed before the 

 cylinder could be inverted without the loss of a drop. 



The elimination of the substances through the kidneys, as 

 well as the rate of flow of the urine, was studied by collecting 

 the urine from cannulse introduced directly into the ureters. 

 In those experiments in which the lymph was collected and 

 analyzed, the directions of Heidenhain * were followed. 



The proteoses, peptones, etc., studied were usually dissolved 

 in 0.7 per cent sodium chloride solution. With substances 

 insoluble in dilute saline fluids, such as heteroalbumose and 

 antialbumid, it was found best to use a few drops of ammo- 

 nium hydroxide to facilitate solution, any excess of ammonia 

 being driven off by heat. The volume of fluid injected was 

 ordinarily 4 c.c. per kilo of body-weight up to a maximum of 

 50 c.c. The doses of the different substances employed were 

 varied hi order to ascertain their relative activity. The injec- 

 tions were accomplished as rapidly as possible, and seldom 

 occupied more than thirty seconds. Indeed, many of the trac- 

 ings show a slight initial rise of blood-pressure due probably 

 to the increased volume of the blood reaching the heart, before 

 the fall caused by the substances injected. 



Specific substances studied. In selecting substances for 

 study we have been influenced by the fact that the evidence 

 already at hand is sufficient for establishing the general action 

 of mixed proteoses and peptones. It has therefore seemed to 

 us desirable to study especially the physiological action of cer- 

 tain well-defined cleavage products with a view to obtaining 

 evidence of the action of the individual bodies present in the 

 ordinary digestion products of the proteids. Thus, an investi- 

 gation of the physiological action of the immediate precursors 

 of antipeptone has seemed especially desirable hi view of the 

 discordant observations of previous investigators with this 



* Heidenhain, Archiv f. d. gee. Physiol., 1891, xlii, p. 209. 



