PROTEINS 



281 



flame and by electric light. The spectrum is continuous. Ob- 

 serve also the incomplete spectrum of the non-luminous bunsen 

 flame. Introduce a small amount of a sodium compound into the 

 flame and observe the yellow band. Such a spectrum is called a 

 bright line spectrum and the particular bands observed are char- 



D 



E 1 



i! I!!, 1 



I 



FIG. 2. ABSORPTION SPECTRA. 



1. Spectrum of sunlight showing' Frauenhofer lines. 



2. Oxyhemoglobin (0.37%). 



3. Hemoglobin. 



4. CO-hemoglobin. 



5. Methemoglobin. 



6. Acid hematin (in ether). 



7. Hemochromogen (reduced alkaline hematin). 



8. Acid hematoporphyrin. 



acteristic of sodium. Observe the spectrum produced by sunlight. 

 Notice the fine dark lines at various intervals. These are the 

 Frauenhofer lines, and the most prominent of them will be used 



