40 



Table III. Comparative analyses of three grains* of Merck's 

 'fibrin from blood" hydrolyzed alone and in the presence of carbo- 



hydrate and of ignited subsoil. 



I Per cent total jPer cent total] Per cent total 

 nitrogen I nitrogen I nitrogen 



*The three gram portion contained approximately 0.4550 gm. nitrogen. 



Table IV. Difference between duplicate analyses (due to experi- 

 mental errors), the differences apparently due to the addition of carbo- 

 hydrate and of ignited subsoil, as well as Van Slyke's "maximum" and 

 <( average" differences to be expected. 



2 The figure in parentheses represents the second greatest difference be- 

 tween duplicates observed by Van Slyke (1911). 



