Figure 15. Spectrogram in the ultraviolet of a preparation 



of native human globin, showing tryptophan band at 290 m[x 



and the phenylalanine bands in the range 250-270 mix. 



Hydrogen arc as light source. 



Figure 16. Photometer record across a 

 spectrogram of a settled suspension of 

 human red blood cells, in the ultraviolet, 

 showing the tryptophan (T) and phenyl- 

 alanine (P) bands. Layer 1-3 cells thick. 



