296 Veterinary Medicine. 



the virulent cultures of tetanus, was easily destroyed by acids, 

 alkalies, hydrogen sulphide, or heat. Like the natural virulent 

 product this may be kept unchanged for months on ice, apart 

 from the light, or with the addition of 0.5 per cent, of carbolic 

 acid, or its own bulk of glycerine. It kills the Guinea-pig in a 

 dose of 0.000025 gramme, and the mouse in a dose of 0.00000025 

 gramme. 



While the propagation of the bacillus in the animal body ap- 

 pears to be local, and the general tetanic symptoms are caused 

 by the absorption of the poison, it remains to be seen on what 

 organ this directly operates, and what accessory conditions favor 

 its efficiency. 



In cases due to inoculation the spasms are at first local in the 

 vicinity of the inoculation wound and later become general. 

 Kund Faber shows that there is no gradual transition from the 

 local manifestations to the general, but the latter appear abruptly 

 and in force as a new and independent phenomenon. When we 

 consider further that in inoculation with pure cultures ( uncon - 

 taminated by pus or saprophytic microbes) the wound often heals 

 promptly, without any sign of remaining local irritation, we may 

 conclude that simple nervous irritation in the sore cannot be in- 

 voked as a cause of the early local spasm. It is more likely due 

 to the local diffusion of the poison into the peripheral nerves while 

 the little that has been absorbed is as yet too much diluted in 

 lymph and blood to seriously derange the nerve centres. 



When general spasms set in it must be assumed that the poison 

 has reached the nerve centres in toxic quantities, either through 

 the circulation or as is alleged by Babes and others through the 

 nerve trunks. When the poison is injected intravenousl)' the 

 general spasms are the first to appear. Again the section of the 

 nerves of a limb before inoculation prevents spasms in its peri- 

 pheral muscles when all the body beside has become tetanic 

 (Tizzoni and Vaillard). The removal of the brain from a tetan- 

 ized frog had no effect, while the removal of a portion of the 

 spinal cord abolished the spasms in the muscles corresponding to 

 that part. Moreover Gumbrecht cut the whole of the sensory 

 nerves of a limb but the spasms occurred in its muscles notwith- 

 standing. It must be admitted, therefore, that the general tetanic 

 spasms are induced by disorder caused by the poison in the spinal 

 nervous centres. 



