46 PROTEIN POISONS 



the animals died. The same powder more finely ground in 

 an agate mortar killed 15 out of 16 animals up to 1 to 

 75,000; out of 28 pigs it killed 9 at 1 to 100,000; out of 8 

 it killed 5 at 1 to 200,000; out of 34 it killed 4 at 1 to 

 2,000,000. Heating the cellular protein for fifteen minutes 

 under 2 kilos of pressure at 134 did not appreciably lessen 

 its toxicity. The finely ground powdered substance killed 

 rabbits when injected intra-abdominally : 2 out of 4 at 1 

 to 75,000; 4 out of 7 at 1 to 100,000; 4 out of 12 at 1 to 

 200,000; and 2 out of 18 at 1 to 2,000,000. 



One gram of the cellular protein was incinerated and the 

 whole ash injected intraperitoneally in a guinea-pig without 

 effect. The toxic effect when subcutaneously injected is 

 practically the same as when employed intraperitoneally, 

 but death is longer delayed. 



The intracellular poison of the diphtheria bacillus was 

 studied by Gelston, 1 using different strains, among which 

 was the well-known extracellular toxin producer desig- 

 nated as Park No. 8. These were grown in Roux flasks, 

 as it was found that this organism does not grow well in 

 the tanks, supposedly on account of limited aeration. 

 The growth scraped from the surface of the agar was placed 

 in physiological salt solution and heated for two and one- 

 half hours at 50 to secure sterilization. This suspension 

 was then poured onto hard filters and placed in an ice-box 

 until filtration was complete. The mass on the filter was 

 washed with sterile physiological salt solution, dried on 

 porous plates over sulphuric acid in vacua, and reduced 

 to a fine powder in agate mortars. It is worthy of note 

 that the physiological salt solution contained small amounts 

 of the extracellular toxin, and that still larger quantities 

 could be obtained by macerating the agar, on which the 

 bacillus had grown, with salt solution. It will be observed 

 that this cellular material was not extracted with alcohol 

 and ether. It killed guinea-pigs when injected subcu- 

 taneously or intraperitoneally up to 1 to 33,000. On post- 



i Trans. Assoc. Amer. Phys., 1902, xvii, 308. 



