the Optical Rotation of the Proteins of Blood Sera. 187 



Table V. — Albumin from the Horse. 





Extinction coefficient. 



Wave-length. 





Specimen 

 number. 













Specific 

 rotation. 



Of head 

 at 2800. 



Of foot 

 at 2500. 



Difference 

 or amplitude. 



Head. 



Foot. 



193 

 194 

 197 

 198 

 199 

 203 



0- 55 



1- 60 

 1 -42 

 0-89 

 119 



32 



1 21 

 0-97 

 0-68 

 -84 



23 

 39 

 "45 

 -21 

 0-35 



2780 

 2780 

 2770 

 2770 

 2800 



2520 

 2540 

 2540 

 2545 

 2550 



o 



-57 -40 



Adopted 



1-20 



0-84 



0-36 



2785 



2545 





Table VI. — Albumin— Human. 



Specimen 

 number. 



Extinction coefficient. 



Wave-length. 



Specific 

 rotation. 



Of head 

 at 2800. 



Of foot 

 at 2500. 



Difference 

 or amplitude. 



Head. 



Foot. 



200 ascitic fluid 



1 -05 



0-86 



0-19 



2770 



2575 



o 



-65 36 



201 „ „ 



0-67 



0-37 



-30 



2765 



2540 



-64 -43 



202 „ „ 



-70 



-38 



0-32 



2795 



2540 



-55 -05 



204 „ „ 



0-58 



0-33 



0-25 



2780 



2540 



-59 -14 



205 normal serum 



*0 -70 



51 



0-19 



2780 



2555 



-50 -58 





f0 -66 



0-45 



0-21 



2790 



2538 



-54 -83 



Adopted 



0-68 



0-45 



0-23 



2783 



2540 





* 1st crop. f 2nd crop. 



The distinction is not in the amplitude alone. The extinction coefficients 

 dt the head and foot of the curve in the horse series are fairly high, while in 

 the human series they are exceptionally low, so that the horse albumin is 

 well differentiated from the human albumin. 



On tabulating the adopted figures for the amplitude of the band, the 

 wave-length of the head and the wave-length of the foot, and extracting 

 their means as shown in Table VII, one is impressed with the uniformity in 

 the wave-length of the head, which is very nearly the same for the three 

 proteins, and yet clearly not identical for pseudo-globulin (2790) and 

 albumin (2784), while the two varieties of eu-globulin provide extremes 

 at 2775 and 2795. The wave-lengths of the foot for the three proteins are 

 also nearly the same, although again clearly differentiated : 2521 for pseudo- 

 globulin, 2531 for eu-globulin, and 2543 for albumin. The differences are 

 small, but there is no reason for doubting that they are real. The approximate 



P 2 



