28 QUATERCENTENARY STUDIES IN PATHOLOGY 



were a large quantity of the bacillus bacteriolysed by the blood of the 

 sheep in vitro, thereafter filtered, and the filtrate injected subcutaneously, 

 I would be enabled to get the toxine in a soluble condition and to study 

 its effects without the complications arising from having the bacillus 

 itself to deal with. 



The following experiment showed that the filtrate thus obtained 

 proved intensely poisonous to the sheep, and induced symptoms which 

 were identical with those of the severest forms of tetanus : — 



A 300 c.c. flask of glucose-beef-tea was inoculated anaerobically with 

 Louping-ill peritoneal liquid taken from an experimental sheep which 

 died from the disease on February 20th, 1904. The culture was allowed 

 to grow for forty-eight hours, and thereafter the supernatant liquid was 

 decanted off and the deposit of bacillus mixed with sheep's serum 

 containing a large percentage of blood corpuscles, as many indeed as 

 could be procured by shaking forcibly the bottle in which the blood was 

 contained. The mixture was covered with sterile olive oil, and placed 

 in the incubator. The blood was obtained from an Aberdeen slaughter- 

 house. 



In the course of twenty-four hours a large number, but not the whole, 

 of the bacilli had been bacteriolysed. Only a few were left, and many 

 of these seemed to be in a state of impending dissolution. The coloured 

 blood corpuscles were still retained in perfect preservation. 



The mixture was passed through a Berkefeld filter, the liquid which 

 came through being quite clear, and, so far as could be ascertained 

 by microscopic examination, free from any bacillus. 



On July 1 6th, 1904, 4 c.c. of the clear filtrate were injected into each 

 thigh of a " Cross " one year old, obtained in the Aberdeenshire market. 

 On the following day, and up to July 28th, nothing was perceived 

 in the condition of the animal worthy of note. On that day it was 

 taken very ill, and on visiting it at 5*30 p.m. it was found to be lying 

 on its side in a perfectly helpless condition, the legs all extended and 

 uplifted, and in a state of extreme rigidity. They could be bent, but 

 with difficulty. The jaw was clenched, but at this period not tightly ; 

 the animal's intelligence seemed to be retained. The neck was stiff and 

 drawn backwards, the eye clear. From time to time there was spasmodic 

 contraction of the limbs, particularly if the animal was approached 

 rapidly, or if disturbed by a sudden noise, as on walking over the stall. 



(28) 



