390 BACTERIOLOGY. 



toxins, and tetanus did not develop; bat if the wounds 

 containing the foreign bodies became infected with 

 other bacteria, tetanus developed and the animals died. 

 From these experiments it seems that a mixed infection 

 is necessary to the development of tetanus when the 

 infection is produced by spores. 



This fact i's of the greatest importance in natural 

 tetanus. Here the infection may be considered as 

 prubably invariably produced by the bacilli in their 

 spore state, and the conditions favoring infection are 

 almost always present. A wound of some kind has 

 occurred, penetrating at least through the skin, though 

 perhaps of a most trivial character, such as might be 

 caused by a dirty splinter of wood, and the bacilli or 

 their spores are thus introduced from the soil in which 

 they are so widely distributed. If in any given case, 

 the tissues being healthy, the ordinary saprophytic 

 germs are killed by proper disinfection at once, a 

 mixed infection does not take place, and tetanus will 

 not develop. If, however, the tissues infected be 

 badly bruised or lacerated, the spores may develop 

 and produce the disease. With regard to the persist- 

 ence of tetanus spores upon objects where they have 

 found a resting-place, Henrijean reports that by means 

 of a splinter of wood which had once caused tetanus 

 he was able after eleven years to again cause the dis- 

 ease by inoculating an animal with the same splinter. 

 The bacilli of tetanus are apparently more numerous 

 in certain localities than in others for example, some 

 parts of Long Island and New Jersey, which have 

 become notorious for the number of cases of tetanus 

 caused by small wounds but they are very generally 

 distributed, as the experiments on animals inoculated 



