vil] 



WAVE-LENGTHS. 



55 



haematin precipitate. Dissolve the hiematin in water containing a trace of 

 HCl. It will give the spectrum of acid-hsematin. To one portion add soma 

 of the decanted fluid and a few drops AmoS, to another add Am^S only. In 

 the former case the h;eniochroniogen formed will gradually become partially 

 converted into Hb (prove by shaking with air and obtaining spectrum of 

 HbOa), ill the latter case the hsemochromogen will remain unaltered. 



LESSON YII. 



WAVE-LENGTHS— DERIVATIVES OP HAEMO- 

 GLOBIN— ESTIMATION OF H^gBMOGLOBIN. 



Spectroscopic Determination of Wave-Lengths. — Use Zeiss's 

 spectroscope, which is provided with an illuminated scale for this 

 purpose. 



1. W.L. of Absorption-Bands of Oxy-Hsemoglobin. 



(a.) Arrange the apparatus as shown in fig. 31. A is the 



Fig. 31. — Arrangement of the Spectroscope for Detennlning Wave-Lengtlis. A. Tele- 

 scope; B. Collimator tube ; C. Scale tube ; D. Haematinometer. 



telescope through which the observer looks at the spectrum 

 obtained by the light passing through B, and dispersed by the 



