CHAPTER XXII. 



THE BACILLUS OF TETANUS. 



IN 1884, Nicolaier, a student in Fliigge's Institute, 

 produced tetanus in mice and rabbits by the subcutaneous 

 inoculation of particles of garden earth, and showed that 

 the disease was transmissible by inoculation from these 

 animals to others. Carle and Rattoiie, in 1884, demon- 

 strated the infectious nature of tetanus as it occurs in 

 man. Finally, Kitasato, in 1889, obtained the bacillus 

 of tetanus in pure culture and described his method of 

 obtaining it and its biological characters. 



The tetanus bacillus occurs in nature as a common 

 inhabitant of the soil, at least in places where manure 

 has been thrown, being abundant in many localities, 

 not only in the superficial layers, but also at the depth 

 of several feet. It has been found in many different 

 substances and places in hay-dust, in horse and cow 

 manure, in the mortar of old masonry, in the dust from 

 horses' hair, in the dust in rooms of houses, barracks, 

 and hospitals, in the air, and in the arrow poison of 

 certain savages in the New Hebrides, who obtained it 

 by smearing the arrow-heads with dirt from crab holes 

 in the swamps. 



Morphology. Motile, slender rods, with rounded ends, 

 0.3// to 0.5/jt. in diameter by 2/j. to 4fj. in length, usually 

 occurring singly, but, especially in old cultures-, often 

 growing in long threads. They form round spores, 



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