276 THE GROUSE IN HEALTH AND IN DISEASE 



After this, work was continued in Cambridge on normal birds which 

 reached us alive, and on sickly birds caught alive, immediately killed and 

 packed in ice and sent to us from time to time from various moors as 

 occasion offered.' 



During the visits to Scotland it was, of course, not possible to carry 

 out all the precautionary measures which are described later as having been 

 taken when working in our own laboratories at Cambridge, but the most 

 important of these precautions were observed, such, for example, as plucking 

 the birds before they were brought into the laboratory, the free use of the 

 flame for singeing, and of the actual cautery for destroying any stray particles 

 of feather, and for burning the skin through which the incisions were made. 

 In the preliminary experiments also the method of getting at the lungs from 

 behind, which is described later, was adopted ; and emulsions of the organs 

 were made between sterilised plates ; but the glass frame, in which this was 

 done at Cambridge, had not been adopted at the time of the earlier 

 experiments. 



One of the first objects of the experiments was to seek for Klein's bacillus, 

 and to compare it with other members of the colon group in the light of 

 First the great advances in bacteriology since Klein's observations were 



hivestiVa'^ made eighteen years ago. The next was to look for characteristic 

 *'°"- " lesions. 



The preliminary observations in Scotland showed at once the presence 



of bacilli of the colon type, which could not be distinguished from Klein's 



bacillus, in the livers and sometimes in the other organs of diseased 



Presence of . ■ i i i 



Bacillus Grouse, but it soon became evident that these micro-organisms might 

 be present also in the organs of Grouse presumably quite healthy. 

 No pneumonia was seen in any of the birds examined by us in a perfectly 

 fresh condition, the lungs being always pale pink in colour and free from 

 congestion. In birds picked up dead on the moor it was not always easy 

 to make a definite statement about the lungs as they were often deeply stained 

 and otherwise altered, but in the fresher specimens it was apparent that 

 there was no pneumonia. In the fresh, diseased birds the livers were not 

 obviously altered, though in those birds which were picked up dead they 

 often showed more or less of that blackish colour, which has sometimes been 

 described as characteristic of " Grouse Disease," but which is certainly due ta 



' Cultures were never made except from birds which reached us alive. 



