154 



TETANUS 



example, a large proportion of wounds, no matter 

 how trifling as wounds they may be, if they are 

 fouled by earth or dirt, result in tetanus. The 

 French in Senegambia have found this to their 

 cost. A gentleman who had' travelled much in 

 Congoland told me that certain tribes poison their 

 arrows by simply dipping the tips in a particular 

 kind of mud. A wound from these arrows is nearly 

 sure to cause tetanus. In many countries, so 

 general and so extensive is the distribution of the 

 tetanus bacillus that trismus neonatorum (tetanus 

 of newly-born infants) is a principal cause of the 

 excessive infant mortality." 



Next, because the tetanus-bacillus has its 

 natural abode in the superficial layers of the soil : 

 here it is associated with a vast number of other 

 organisms, so that its identification and isolation 

 were a work of immeasurable complexity. What 

 mixed company it keeps, is shown by Houston's 

 estimate of the number of microbes per gramme 

 in twenty-one samples of different soils. This 

 number ranged from 8326 in virgin sand, and 

 475,282 in virgin peat, to 115,014,492 in the soil 

 from the trench of a sewage-farm. In all rich and 

 well-manured soil the tetanus-bacillus may possibly 

 be present ; but it was the work of years to 

 dissociate it from the myriads of organisms out- 

 numbering it. 



Next, because it cannot be got to grow in 

 cultures exposed to the air : its proper place is 

 below the surface of the soil, away from the air ; it 

 is " strictly anaerobic," and the attempts to culti- 



