viii THE EFFECT OF SUBLIMATE ON ALBUMIN 313 



Result : The saturated sublimate-salt solution formed a sediment 

 consisting of coarser flocculi than the saturated watery sublimate 

 solution, and therefore did not settle down as firmly as the former. 

 The sediments formed by the half-saturated solutions only settle down 

 to one-half the extent of those formed by the saturated ones. 



There was no difference noticeable in the sediments of the two 

 half-saturated solutions, while the supernatant fluid in that test-tube 

 containing the half -saturated salt -sublimate mixture was opalescent, 

 because the salt leads to the formation of some very fine coagula, or 

 partly dissolves the mercury precipitate. After shaking up the two 

 half -saturated solutions, the one containing salt settles more quickly. 



General conclusions : Sodium chloride, if present in even minute 

 traces, has a distinct solving action on the sublimate precipitate, and 

 if it be to the sublimate in the proportion of 3 : 7 gram weight (Experi- 

 ment 8 A, D) the formation of a solid coagulum is prevented altogether, 

 the albumin-molecules being fixed separately give rise to a fine 

 opalescent emulsion. Still further additions of salt, especially if the 

 amount of gram weight of sodium chloride to the sublimate is as 

 5'84 : 1'35, prevent coagulation altogether (Experiment 8 B, /), because 

 the sodium chloride, by its ready dissociation into sodium-ions and 

 chlorine-ions, saturates the watery solution with the latter, and thereby 

 prevents any more chlorine -ions being formed. Sublimate, which 

 would normally break up hydrolytically according to the formula 

 HgOH + 2HC1, and its hydrochloric acid into the hydrogen-ion with 

 an acid reaction and the chlorine-ion, cannot do so now, as the 

 formation of chlorine-ions in a solution already saturated by them is 

 impossible. 



When sublimate, therefore, is used in strong NaCl solutions it 

 cannot dissociate hydrolytically, and no hydrogen-ions being formed 

 the reaction of the sublimate and salt solution remains neutral, as has 

 already been noticed by Lee and Mayer. 1 



When a proteid, coagulated by sublimate, is treated with a solu- 

 tion of sodium chloride it becomes soluble, because we are dealing 

 with the following changes : From a table of electro-affinities 2 it will 



1 Lee and Mayer : Grundziige d. mikr. Technik, 1901, p. 43. 



- Abegg and Herz, Ohemisches Practiciim, Vandenhoek and Ruprecht, Gottingen, 1900 

 (English edition, Macmillan), gives the following table of electro- affinities : 

 Kat-ions arranged in descending order of their electro-affinities 



K, Na, Li, Ba, Sr, Ca, Mg, Al, Mn, Zn, Cd, Fe, CO, Mi, Pb, 



H, Cu, Ag, Hg, Pt, Au. 



An-ious arranged in descending order of electro-affinities 



(F, N0 3 , C10 3 ), (Cl, So 4 ), Br, I, P0 4 , C0 3 , Cr0 4 , Si0 3 , SH, H 2 B0 3 . 

 OH, CN, 0, S. 



