82 BLOOD. 



previous paragraph with air, and observe that the one 

 band disappears and the two bands reappear. The 

 one band is peculiar to reduced or venous, the two 

 bands are characteristic of oxydised or arterial hemato- 

 crystalline. 



9. Treat some diluted hematocrystalline solution or 

 blood with carbonic oxyde, and notice that the colour 

 becomes more bluish than either arterial or venous 

 blood, and that the spectrum is that of arterial blood, 

 but that the bands are moved a little more towards 

 the violet end. This combination of carbonic oxyde 

 with hematocrystalline cannot be dissolved by any 

 rediicing agent, and is the cause .of death in cases of 

 poisoning by charcoal vapours. 



10. Treat some diluted blood with nitrous oxyde gas 

 and observe that the absorption bands become a little 

 paler. This is due to the expulsion of oxygen from 

 and the combination of nitrous oxyde with the hemato- 

 crystalline. 



11. Treat a solution of blood with hydrothion or 

 ammonium sulphide, and observe that the spectrum 

 becomes changed, three bands as in the following 

 engraving making their appearance. 



AaBC D Eb F G HH 



Spectrum of Blood treated with hydrothion. 



12* Treat some hematocrystalline with acetic or 



