Scientific Proceedings. 



8 9 



Examples of the experimental data are appended : 



Defibrinated Blood Laked Blood 



Spec. Grav. Viscosity Spec. Grav. Viscosity 



I.0566 665.74 I.0563 982.35 



61 (204) 



The determination of ammonia and urea in blood. 

 By W. MCKIM MARRIOTT and 0. G. L. WOLF. 



[From Cornell University Medical College, New York City.'] 



Ammonia is determined by distillation in vacuo. 100 c.c. of 

 blood are treated with 50 c.c. of saturated sodium chlorid solution 

 and 250 c.c. of methyl alcohol are added to the mixture. The pre- 

 cipitate formed is finely granular. The residue is filtered off in a 

 filter press, and the filtrate distilled for 40 minutes, with the tem- 

 perature of the water bath at 40-50 °C. The receivers are charged 

 with «/50 sulphuric acid, and the acid titrated with nj$o sodium 

 hydroxid free from carbonate. Sodium alizarin sulfonate is used 

 as an indicator. The results are perfectly accurate. 



The residue after distillation is made acid with hydrochloric 

 acid, evaporated and hydrolyzed with 10 grams of glacial phos- 

 phoric acid at 1 5o°C. The ammonia formed from the urea is then 

 distilled into nj$o acid. The duplicates have shown very satis- 

 factory agreement, but it is quite certain that not all the urea which 

 is added to a sample of blood is recovered. It is probable that 

 the carbohydrates in the residue combine with the urea at the 

 temperature of hydrolysis and prevent the formation of ammonia. 



62 (205) 



The resolution of fibrinous exudates, with exhibition 

 of specimens. 



By EUGENE L. OPIE. 



[From the Rockefeller Institute for Medical Research.^ 



The purpose of the experiments which are described has been 

 to determine the part played by enzymes in the resolution of a 

 fibrinous exudate. When turpentine is injected into the subcu- 

 taneous tissue of the dog, an abscess results, but when an equal 



