1905.] Crystalloids and Colloids through Gelatine. 317 



Eesidual Fluid : Titrated immediately after decompression (100), after 

 12 hours in the filter case (110). 



Conclusion. — On renewing filtration the filtrate may contain a higher 

 percentage of salt than the original fluid, due probably to the temporary 

 decompression, for on continued recompression the concentration tends to 

 become less than (100). 



Continued Filtration of Sodium Chloride with Megatherium Lysin and 

 Antilysin through 9 per cent. Gelatine. 



In a former paper,* mixtures of lysin and antilysin were pressed 

 through gelatine which had been tested for tightness by the filtration of 

 saline. The redistribution of salt under these circumstances was now 

 determined. 



Method. — A filter through which 10 c.c. of 0'81 per cent. NaCl had been 

 pressed, the original gelatine being 9 per cent, in 0'81 per cent. NaCl, was 

 decompressed, the residual salt solution removed, and the filter case refilled 

 with 120 c.c. of a nearly neutral mixture of equal volumes of a fluid 

 megatherium lysin and 5 per cent, antilysin in saline, of which 75 cc. in 5 c.c. 

 fractions were pressed through. 



Examination for Sodium Chloride. — Experiment No. 2b, Table I, is one of 

 two practically identical nitrations. 



Original Fluid : Contained 0"81 per cent. NaCl = (100). Hemolytic 

 Index (16-8). 



Filtrates : As in No. 2a the 1st and 2nd fractions were the most con- 

 centrated in NaCl, but they did not reach (100), and the final fraction was 

 (96 - 4). The average hsemolytic index of the whole filtrate was (0'5). 



Eesidual Fluid : The results were entirely similar to those of No. 2a as 

 regards NaCl. Hsemolytic Index (38'6). 



Conclusion. — The redistribution of salt is insufficient to give a trace of 

 haemolysis under standard conditions. 



Temporary decompression even for a few minutes allows a higher per- 

 centage of salt to pass into the filtrate than would be obtained by constant 

 pressure. 



Filtration of Sodium Chloride with Butyric Acid through 9 per cent. 



Gelatine. 



Butyric acid in saline acts as a very stro'ng hemolysin, and, as it possesses 

 crystalloidal properties, it appeared to be of interest to compare its filtration 

 phenomena with those of megatherium lysin in saline. Further, butyric 



* Loc. cit. 



