Carbon Dioxide of Injury in Nervous Tissue. 39 



Ringer's solution (Table II., Fig. 2). In the small quantities of 

 fluid a strong acid reaction developed during the hour. This led 

 to rigor and opacity of the muscle by the end of the fourth hour. 

 This change was accompanied by a marked increase in the rate of 

 acid output not only in the muscle but in the medulla and in the 

 sciatic nerves. Probably death changes were also occurring in 

 the nervous tissues. Where sufficient solution was present to 

 maintain neutrality, no secondary maximum of acid production 

 developed. 



It will be noted from the graphs and tables that a marked fall 

 in rate occurs during the first hour, and that the medulla has a 

 higher rate of acid production than muscle while the sciatic nerve 

 has an extremely low rate. Under appropriately headed columns 

 of the tables are given the ratios of rate of acid output in the sciatic 

 nerves to that of the medulla and to that of the muscle of the same 

 animal. In view of the fact that Mathews 1 states that the respir- 

 atory rate of nerve fibers is "higher than that of any other tissue 

 examined," it is interesting to note that under identical conditions 

 of experiment, nerve fibres produce carbon-dioxide at 10-20 per 

 cent, of the rate of the medulla and at 15-30 per cent, of the rate 

 of muscle. 



23 (1398) 



Volumetric analysis of ion-protein compounds. 



By Jacques Loeb. 



[From the Laboratories of the Rockefeller Institute for Medical 

 Research, New York.] 



The speaker demonstrates that gelatin at pH > 4.7 combines 

 only with cations and at pH < 4.7 only with anions, while at the 

 isoelectric point (pH = 4.7) it combines with neither anion nor 

 cation. 



He shows further that the curves representing the influence of 

 monovalent anions or cations upon the swelling, osmotic pressure 

 and viscosity of gelatin are always approximately parallel with the 

 curves representing the amount of anion or cation found in chemical 

 combination with the gelatin. 



1 Mathews, A. P., "Physiological Chemistry, p. 590, 1915. 



