1897J MICROSCOPICAL JOUKjnAL. 221 



Meth^tsmoglobin. 



The spectrum of Methsemoglobin is obtained by first 

 preparing Oxy-HsBmoglobin 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 liquid is separated from the crys- 

 tals by filtering throug'li muslin or linen, squeezing the 

 mass so as to obtain the crystals in as pure a form as 

 possible. The crystals are dissolved in distilled water 

 and a dilute solution is examined with the spectroscope. 

 The two bands of Oxy-Haenioglobin appear. A few drops 

 of potassium permanganate are added and the solution 

 gently warmed. If sufficient time has elapsed for the 

 oxidation of the Oxy Hemoglobin, 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 oxidation has taken place it will be 

 seen. In the experiment at hand I left the solution 

 until the next day, before it would give the above 

 result. 



Ca1{B0N-M0N0XIDE H^llMOGLOBIN. 

 If coal gas bo passed through blood which has been 

 delibriiiated, it will assume a cherry-red color, the car- 

 bon-monoxide of the gas having driven off the oxygen of 

 llic Oxy-H;enioglobin and taken its place. The reducing 

 agents have no influence upon ttiis new substance, it being 

 more stable than Oxy-HaBmoglobin. The two absorption 

 bands are nearer to E than in the Oxy-Ha^moglobin 

 spectruui. 



H^MATIN. 



The red coi'puscles are composed of a proteid stroma 

 and a brownish pigment v/hich is called hsematin. The 

 iron is a part of the ha3matiu. It can be obtained either 

 as the acid hsematin or the alkaliiae hsematin. 



