3 oo 



PHYSIOLOGICAL CHEMISTRY 



phosphate, 1 iron, 2 iodin, 3 phenols, 4 amino acids, 5 amylase 6 and other 

 substances. 



Spectroscopic Examination of Blood 3 



Either the angular- vision spectroscope (Figs. 98 and 99) or the 

 direct-vision spectroscope (Fig. 97) may be used in making the spec- 

 troscopic examination of the blood. For a complete description of 

 these instruments the student is referred to any standard text-book of 

 physics. 



FIG. 97. DIRECT-VISION SPECTROSCOPE. 



i. Oxyhemoglobin. Examine dilute (1:50) defibrinated blood spectro- 

 scopically. Note the broad absorption band between D and E. Continue the 

 dilution until this single broad band gives place to two narrow bands, the one 

 nearer the D line being the narrower. These are the typical absorption bands 



FIG. 98. ANGULAR-VISION SPECTROSCOPE ARRANGED FOR ABSORPTION ANALYSIS. 



of oxyhemoglobin obtained from dilute solutions of blood. Now dilute the blood 

 very freely and note that the bands gradually become more narrow and, if the 

 dilution is sufficiently great, they finally entirely disappear. 



^ell, R. D., and Doisy, E. A.: Jour. Biol. Chem., 44, 55, 1920; Bloor, W. R.: Jour. 

 Biol. Chem., 45, 171, 1920; Meings, E. B.: Jour. Biol. Chem., 36, 335, 1918; Bloor W. 

 R.: Jour. Biol. Chem., 36, 33, 1918. 



2 Berman, L.: Jour. Biol. Chem., 35, 231, 1918. 



3 Kendall, 'E. G., and Richardson, F. S.: Jour. Biol. Chem., 43, 161, 1920. 



4 Benedict, S. R., and Theis, R. C.: Jour. Biol. Chem., 36, 95, 1918. 



6 Bock, J. C.: Jour. Biol. Chem., 28, 357, 1917; Okada, S.: Jour. Biol. Chem., 33, 325, 

 1918; Gary C. A.: Jour. Biol. Chem., 43, 477, 1920; Van Slyke, D. D., and Meyer, V. C.: 

 Jour. Biol. Chem., 12, 399, 1912. 



6 Lewis, D. S., and Mason, E. H.: Jour. Biol. Chem., 44, 455, 1920. 



