468 



THE BLOOD 



[CH. XXIX. 



not so well defined as the a or bands. On dilution it fades rapidly ; 

 so that in a solution of such strength that both bands of oxyhsemoglobm 



ABC 



Fio 333 -Graphic representations of the amount of absorption of light by solution of (1) oxyhsemo- 

 'globin, (II) of hemoglobin, of different strengths. The shading indicates the amount of absorption 

 of the spectrum ; the figures on the right border express percentages. (Rollett.) 



would be quite distinct, the single band of haemoglobin has disappeared 

 from view. The oxyhaemoglobin bands can be distinguished in a 

 solution which contains only one part of the pigment to 10,000 of 

 water, and even in more dilute solutions which seem to be colourless 

 the a band is still visible. 



A HK L M isj 



FIG. 334. The photographic spectrum of haemoglobin and oxy haemoglobin. (Gamgee.) 



Haemoglobin and its compounds also show absorption bands in 

 the ultra-violet portion of the spectrum. This portion of the spectrum 



