II SYMPTOMS AND PATHOLOGY 19 



sometimes to a considerable extent. In some cases 

 the peritoneum appears very moist in these locaHties ; 

 that is to say, there is a small amount of exudation. I 

 have seen a few cases in which haemorrhage has taken 

 place, showing itself in the form of petechise in the 

 peritoneum. 



From this we see that the grouse dead of the 

 disease show a definite series of pathological appear- 

 ances, in which the congestion of the lungs and liver 

 is very conspicuous. 



The above considerations led me to conclude that 

 the disease was an acute infectious disease, and owing 

 to the constantly congested and diseased condition of 

 the lungs and liver, I thought it possible that the 

 disease belonged to the group of diseases in which 

 the microbe caused the disorder by its multiplication 

 in the blood. The first birds dead of the disease 

 which I dissected in June 1887, ^^ Ayrshire, w^ere 

 examined with the view of discovering the microbe 

 in the blood. Cover-glass specimens were made of 

 the heart's blood and of the blood of the lung, i.e. 

 a thin film of blood was dried on cover-glasses and 

 then stained in the usual manner with aniline dyes 

 — methyl blue or gentian violet ; but on micro- 

 scopic examination no bacteria could be discovered. ; 

 Numerous tubes, some containing nutrient gelatine, '\ 

 others nutrient Agar, were inoculated in the usual 



