107 



bands only one appears, wliich is hetween the two lines of Oxy.-Hnmoghhin, and is 

 much broader than either of the bands mentioned above. This is the spectrum of 

 reduced 0.ry.- Hemoglobin or simply Hirmoglobin. 



METH.EMOGLOBIN. 



The spectrum of Methirmoglobiii is obtained by first preparing Oxy.- Humoglobin 

 crystals by treating dog's blood with ether and shaking it until it becomes laky, 

 then allowing it to stand in a cool place for an hour or so, at which time a firm 

 mass will be formed, due to the crystals. The mother liquor is separated from 

 the crystals by filtering through muslin or linen, squeezing the mass so as to ob- 

 tain the crystals in as pure a form as possible. The crystals are dissolved in dis- 

 tilled water and a dilute solution is examined with the spectroscope. The two 

 bands of Oxy.-Hiemoglobin appear. A few drops of potassium permanganate .are 

 added and the solution gently warmed. If sufficient time has elapsed for the ox- 

 idation of the Oxy.-Hcemoglobm, the two bands will have disappeared and instead a 

 single band in the red near the line C between C and D. Nearly the entire spec- 

 trum is absorbed. Sometimes it is a little difficult to get this band, but if the ox- 

 idation has taken place it will be seen. In the experiment at hand I left the so- 

 lution until tlie next day before it would give the above result. 



CARBON-MdNOXIDE H.EMOGLOBIN. 



If coal gas be passed through blood which has been defibrinated, it will as- 

 sume a cherry-red color, the carbon-monoxide of the gas having driven off" the 

 oxygen of the Oxy.-H<vmoglobin and taken its place. The reducing agents have no 

 influence upon this new substance, it being more stable than Onj.-H<i'moglobin. 

 The two absorption bands are nearer to E than in the Oxy.-Hcemoglobin spectrum. 



H.EMATIN. 



The red corpuscles are composed of a proteid stroma and a Ijrownish pigment 

 which is called hfematin. The iron is a part of the h:ematin. It can be obtained 

 either as the acid hfematin or the alkaline h;ematin. 



In making the acid h.ematin, I took 100 cc. of 95 per cent, alcohol and added 

 2 cc. of sulphuric acid, and then 10 cc. of blood; the mixture was boiled for about 

 an hour in a flask tube three or four feet long so that the vapor passing off would 

 1)6 condensed in upper part of the tube and flow back into the flask. 



During this process a precipitate is formed which is acid hanuatin. The so- 

 lution is filtered and the precipitate is dissolved in alcohol and then examined 



