dealing with the Phenomena of " Clot" Formations. 365 



of the action of chlorides on the permeability of certain vegetable tissues 

 follows in the same order. 



The breadth of the zone of instability is also affected by the concentration 

 of the salts contained within the gel. When the gel is made by heating a 

 solution containing 2-per-cent. sodium cholate and 3N/80 calcium chloride, 

 with no other added salt, the diphasic character of the curve is only marked 

 in the cases where lithium and magnesium chlorides are in the eroding fluid ; 

 in both these cases two maxima in the curve can be observed ; in the cases of 

 sodium and potassium chlorides only faint indications of a diphasic character 

 are obtained.* The experimental results are given in Table II. 



Table II. — Erosive Action (measured in mm.) of Salts on Gel containing no 

 Added Salt. Gel 2 c.c. 4-per-cent. Sodium Cholate + 0"5 c.c. 3N/10 

 CaCl 2 +l-5 c.c. H 2 0. 





Concentrations of salt solutions. 



0. 



N/20. 2X 20. 



3X/20. 4N/20. 



5N/20. 



6N/20. 



7N/20. 



8N/20. 



9N/20. 



IOjST/20. 



LiCl 



12 



13 



13 



22 



20 



15 



16 



23 



30 



38 



60 



XaCl 





12 



6 



12 



18 



26 



42 



54 



73 



>75 



>75 



KC1 





10 



7 



9 



14 



26 



35 



47 



66 



67 



71 



MgCl 2 ... 





9 



19 



11 



15 



27 



42 



51 



52 



55 



61 



Both the breadth of the " zone of instability " and the amount of erosion 

 within this zone can be increased, however, by increasing the concentration 

 of the salts within the gel. The results illustrating this statement are given 

 in Table III, and plotted graphically in fig. 2. In these experiments the gels 

 were made by heating the following solutions :— 



2 c.c. 4-per-cent. sodium cholate + 0"5 c.c. 3N/10 CaCl 2 + 1*5 c.c. 2N/9 KC1. 



1-5 c.c. 3N/9 KC1. 

 1-5 c.c. 4N/9 KC1. 



The concentration of potassium chloride in these gels was, therefore, N/12, 

 N/8, and N/6. The eroding solution used was that of sodium chloride. 



The influence of certain non-electrolytes on gels was also investigated. 

 Dextrose solutions have practically no erosive action on the gels, whether 

 they contain added salts or not. On the other hand, the erosive action of 

 salt solutions on gels containing dextrose is similar to that on gels containing 



* The curves are not reproduced in this paper. 



