Carnaubic Acid from Beef Kidneys. 



59 



Weights in grams: substance, 0.1590: C0 2 , 0.4556; H 2 0, 0.1870 

 Percentage Elementary Composition 

 Found Calculated for C 21 H ls O, 



C 79.147 C 78.159 



H 13.161 H 13.156 



O 8.691 O 8.684 



Analysis of the ethyl ester : 



Weights in grams : substance, o. 1414; C0 2 , 0.4079; H 2 0, 0.1677 



Percentage Elementary Composition 

 Found Calculated for C 2 H 5 C 21 H 41 0 2 



C 78.670 C 78.6S5 



H 13.271 H 13.245 



O 8.059 O 8.070 



Analysis of the silver salt : 



Weights in grams : substance, 0.5294 ; Ag, o. 1208 

 Percentage Content of Silver 

 Found Calculated for Ag C s4 H 17 0 2 



22.8l8% 22.703% 



The carnauba acid obtained from carnaubic wax has the same 

 percentage composition and is recorded as melting at 72. 5 0 . 



33 (289) 



The change of corpuscle resistance in the blood of immunized 

 animals, coincident with the formation of anti-bodies. 



By FREDERICK P. GAY. 



[From the Pathological Laboratory of Harvard University.] 



In logical sequence to the studies on isohemagglutination of 

 human blood, the results of which have been presented to this 

 Society 1 and recently published in detail, have followed estima- 

 tions of certain physico-chemical properties of the blood of normal 

 and of immunized animals. In human bloods three rather definite 

 groups were found as regards interagglutination of corpuscles, 

 groups which correspond to relative differences in tonicity of the 

 bloods in question. The method principally relied on in the esti- 

 mation of differences in the molecular concentration of various 

 human bloods was that of the relative susceptibility of the respec- 

 tive blood corpuscles to hemolysis by salt solutions of different 

 concentrations, a method which has been employed by Hamburger 

 and others as the most delicate for this purpose. 



1 This Journal, 1907, v. p. 14. 



