2CO THE BLOOD. 



by careful purification, and also the reverse, namely, a globulin insoluble in 

 water can sometimes be converted into one soluble in water by allowing it to lie 

 in the air. An insoluble protein like casein can also, according to HAMMARSTEN, * 

 have the solubilities of a globulin due to contamination with constituents of the 

 serum, and K. MORNER 2 has also shown that a contamination of the serum- 

 globulins with soap can essentially modify the precipitation of these globulins. 

 Under these circumstances the above assumptions in regard to the different 

 globulin fractions must be accepted with great caution. 



The investigations made thus far upon the so-called serglobulin, 

 have not led to any positive results. That this globulin, with the 

 exception of the enzymes, antienzymes, immune bodies, and other 

 unknown substances which are carried down by the various fractions, is 

 a mixture of globulins there seems to be no doubt. The serglobulin or 

 the globulin mixture which is obtained from the serum by the methods 

 to be described has the following properties: 



In a moist condition it forms snow-white flaky masses, neither tough 

 nor elastic, which always contain thrombin and hence can bring about 

 coagulation in a fibrinogen solution. The neutral solution is only incom- 

 pletely precipitated by NaCl added to saturation, and is not precipitated 

 by an equal volume of a saturated salt solution. It is only partly 

 precipitated by dialysis or by the addition of acid. On saturation with 

 magnesium sulphate, or one-half saturation with ammonium sulphate 

 a complete precipitation is obtained. The coagulation temperature 

 is, with 5-10 per cent NaCl in solution, 69-76, but more often 75 C. 

 The specific rotation of the solution containing salt is (a)j>= 47.8 

 for the serglobulin from ox-blood (FREDERICQ 3 ) . The various globulin 

 fractions do not differ essentially from each other in their coagulation 

 temperatures, specific rotation, refraction coefficient (REiss 4 ), and their 

 elementary composition. The average composition is, according to 

 HAMMARSTEN, C. 52.71, H 7.01, N 15.85, S 1.11 per cent. K. MORNER 5 

 found 1.02 per cent sulphur and 0.67 per cent lead-blackening sulphur. 

 All the sulphur seems to exist as cystine. 



Serglobulin contains, as K. MORNER first showed, a carbohydrate 

 group which can be split off. LANGSTEIN 6 has obtained several car- 

 bohydrates from the blood-globulin, namely, glucose, glucosamine, 



1 See Hammarsten, Ergebnisse, d. PhysioL, 1, Abt. 1. 



2 Zeitschr. f. physiol. Chem., 34. 



3 Bull. Acad. Roy. de Belg. (2), 50. In regard to paraglobulin, see Hammarsten, 

 Pfliiger's Arch., 17 and 18, and Ergebnisse d. Physiol., 1, Abt. 1. 



4 Hofmeister's Beitrage, 4. 



6 Zeitschr. f. physiol. Chem., 34. 



6 M6rner, Centralbl. f. Physiol., 7; Langstein, Munch, med. Wochenschr., 1902, 

 1876, and Wien. Sitzungsber., 112, Abt. 116, 1903; Monatsheft f. Chem., 25; Hof- 

 meister's Beitrage, 6; see also footnote 5, p. 84. 



