OF HEMOGLOBIN, AND ITS SPECIFICITIES. 



75 



Physiologie, Phys. Abth., 1907, 209) have determined the molecular weights 

 by means of osmotic pressures. Jutt's (Inaug. Dissert., Dorpat, 1894; 

 Maly's Jahr. li. d. Fort. d. Thierchemie, 1895, 128) estimates were founded 

 upon the combinations of hemoglobin with heavy metals. Kulz (Zeit. f. 

 physiolog. Chemie, 1883, vn, 384) based his calculation upon the com- 

 bining power of hemoglobin with CO. Hiifner and Ganser made use of the 

 hemoglobin of the horse and bullock, freshly produced, free from alcohol, 

 and crystallized three times without alcohol. The mean value of the hemo- 

 globin of the bullock they found to be 16321, and of that of the horse 15115. 

 They state it is doubtful whether the molecular weights of hemoglobins of 

 the bullock and horse are the same or different ; that the results of these latest 

 experiments agree with the mean values formerly obtained; and that the 

 molecule of oxyhemoglobin is composed of and of reduced hemoglobin. 



TABLE 27. The molecular formulas and iveights of hemoglobin, according 



to various observers. 



While the formulas given vary materially, the most striking differ- 

 ence will be noted to be in the ratios of the percentages of Fe to S (table 

 26). Otto (Zeit. f. physiolog. Chemie, 1882, vn, 65) found that the hemo- 

 globins of the dog and pig are practically identical as regards elementary 

 composition and their coefficient of extinction, and that a close if not 

 complete identity exists in the combining power with 0. These hemo- 

 globins, he calculates, each contain 1 atom of Fe to 3 of S. Kulz estimated 

 the same ratio for the hemoglobin of the pig, and Preyer the same ratio 

 in the hemoglobin of the dog. But in the case of the horse and bullock the 

 ratio is 1 of Fe to 2 of S. 



THE SOLUBILITY OF HEMOGLOBIN. 



The most marked differences noted in the hemoglobins of different 

 species have been in the degree of solubility and in the quantity of water 

 of crystallization. While the determinations of solubilities are extremely 

 limited and far from satisfactory, because of obvious impurities of the sub- 

 stances experimented with and the failure at times to record temperatures, 

 they nevertheless show clearly very wide differences. Crystals of bullock's 

 and pig's blood, for instance, are soluble in their water of crystallization 

 at ordinary room temperature, while the crystals of raven's blood are 

 practically insoluble in cold water, and between these extremes there are 

 all gradations. 



