VIII 



THE SALTING-OUT OF ALBUMINS 



285 



that the above order, in which salts precipitate electro-negative albumins, 

 is the same as that in which they prevent the imbibition of water 

 by gelatine-plates and in which they increase the melting point of 

 gelatine. 



Pauli 1 has carefully investigated the effect which is produced on 

 eggwhite by the addition of the neutral salts of the alkalies and of 

 magnesium. In the first instance he confirms Schafer's observation 

 (see p. 290) that two salts in combination will do what one salt by 

 itself is unable to do, for if potassium or sodium chloride and sodium 

 acetate be used in such strengths as not to cause coagulation, they 

 will on being mixed give rise to coagulation, and KC1 + NaC 2 H 3 0. ? 

 will produce a greater effect than if NaCl + NaC 2 H 3 2 are used. In 

 the former case the kation is different in the two salts, while in the 

 latter case they are the same. 



The dibasic magnesium sulphate + the monobasic sodium chloride 

 also augment mutually their coagulating efficiency, as is proved by 

 the following table given by Pauli : 



To 2 ccm. of eggwhite were added 8 ccm. of a 4 '5 normal MgS0 4 

 solution in the quantities stated, and then weighed amounts of 

 crystalline NaCl. 



W. Pauli, Hofmeister's Beitrage, 3. 225 (1903). 



