148 



Scientific Proceedings (59). 



served in action correspond to the difference in concentration. 

 Also, for a given degree of action the molecular concentration is 

 not the same for all substances, and though the evidence has not 

 yet been completely analyzed, it seems to be in general agreement 

 at least, with the views of Meltzer and his pupils, 1 that the toxicity 

 of solutions of salts that naturally occur in the blood varies in- 

 versely with the amount in which they are thus present. 



90 (907) 

 The blood in " shock." 

 By C. C. Guthrie and F. V. Guthrie (by invitation). 

 [From the Physiological Laboratory, University of Pittsburgh.] 



It has been stated that in conditions of "shock" concentration 

 of the morphological elements of the blood may take place through 

 outward passage of liquid from the blood vessels. 2 



This point was investigated in a rather comprehensive experi- 

 mental study of "shock" in etherized dogs. This condition was 

 induced by rhythmical Faradic stimulation of the brachial 

 plexuses and moderate hemorrhage. In general, death occurred 

 within one or two hours. Small samples of the blood were with- 

 drawn at regular intervals and defibrinated. The specific gravities 

 and freezing points of the blood specimens were measured in 

 eight experiments. The results are practically the same in all 

 cases, and show that under the conditions of the experiments, 

 physical alterations in the blood are not greater than may be 

 accounted for by the loss of blood and certainly are not such as 

 could affect the circulation sufficiently to account for the phe- 

 nomena observed. 



Relative to the total mass of blood, the amount withdrawn was, 

 in round numbers, between 15 and 30 per cent... the average being 

 25 per cent. — estimated on the total blood being 1/15 of the 

 body weight. 



The average arterial blood-pressure at the time the first blood 

 sample was taken was 180.5; at the time of taking the last sample 



1 Jr. Pharm. and Exp. Ther., 1909, I, 1. 



2 Malcolm, Lancet, 1905, II, 573; 1907, I, 497. 



