190 



ESSENTIALS <>F fUlKMK'AL I'M YSF<>L< )(l V 



caustic potash and boil. The colour changes to brown, and with the 

 spectroscope a faint shading on the left side of the D line is seen (fig. 57, 

 spectrum 8). 



(6) The band is much better seen in an alcoholic solution. Prepare the 

 following mixture : 150 c.c. of 90-per-cent. alcohol, and 18 c.c. of 50-per- 

 cent, potash. Take about 5 c.c. of this mixture in a test-tube and boil it. 



FIG. 58. The photographic spectrum of haemoglobin oxyhsemoglobin. (Gamgee.) 



G WK LM N O 



Fro. 59. The photographic spectrum of oxyhaemoglobin and methaemoglobin. (Gamgee.) 



While still hot drop into it a few drops of undiluted defibrinated blood. The 

 fluid then shows the spectrum of alkaline haematin. This may then be used 

 for the next experiment. 



6. Haemochromogen. Add ammonium sulphide to the solution of alkaline 

 the colour changes to red, and two bands tire seen, one between D 



