TYPHOID AGGLUTINATION 419 



blood dried at a low temperature and kept dry may 

 retain its agglutinative power for a long time. 



While there is no constant connection between the 

 activity of agglutination and the severity of the disease, 

 active agglutination tends to go with cases which recover, 

 and cases in which agglutination is feeble or absent tend 

 to be severe. 



Many chemical substances may produce agglutination 

 of typhoid bacilli, so that it is necessary to exclude them 

 in making a diagnosis. For example, corrosive sublimate 

 (0'7 : 1,000), alcohol, salicylic acid, vesuvin, and safranin 

 (1 : 1,000) agglutinate, while carbolic and lactic acids, 

 chloroform, caustic soda, and ammonia do not, the two 

 last only provided the test typhoid emulsion be made 

 with distilled water. Safranin has a powerful aggluti- 

 nating action on the typhoid bacillus, but not on the colon 

 bacillus. 



Toxins. Ptomines, toxic proteins and proteoses were 

 stated to have been obtained from cultures or from the 

 cadaver by Brieger, Frankel, Fenwick and Bokenham, 

 Sidney Martin, and others. 



The toxins of the typhoid bacillus are, however, endo- 

 toxins, and filtered broth cultures are usually almost non- 

 toxic. Macfayden and Rowland, 1 by disintegrating large 

 quantities of typhoid bacilli, filtering, and so obtaining the 

 intra -cellular constituents in the filtrate, found that small 

 doses of the latter produced a transient rise of temperature 

 in guinea-pigs and a loss of weight which was soon re- 

 covered from. Animals so treated were protected against 

 a certain lethal dose of typhoid bacilli, and their blood 

 exhibited agglutinative and bacteriolytic properties 

 towards the typhoid bacillus. Macfadyen 2 later obtained 

 the intra-cellular juice of typhoid bacilli by disintegration 



1 Gentr. /. Bakt., xxx, p. 753. 



2 Proc. Roy. Soc. Lond., B, Ixxi, 1902, p. 77. 



