VII.] 



WAVE-LENGTHS. 



55 



hseinatin precipitate. Dissolve the hsematin in water containing a trace of 

 HC1. It will give the spectrum of acid-hfematin. To one portion add some 

 of the decanted fluid and a few drops Am 2 S, to another add Am,S only. In 

 the former case the haemochromogen iormed will gradually become partially 

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

 Hb0. 2 ), in the latter case the haemochromogen will remain unaltered. 



LESSON VII. 



WAVE-LENGTHS DERIVATIVES OP HAEMO- 

 GLOBINESTIMATION OF HEMOGLOBIN. 



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 Determining Wave-Lengths. A. Tele- 

 scope; B. Coll ima tor 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 



