SECRETARY'S REPORT. 71 



The Board of Medical Examiners have been unable to find 

 any absolute marks by which the pathological appearances of 

 one kind of pleuro-pneumonia can be distinguished from 

 another. 



If there is induration of the lung, effusion of lymph and 

 serum, pus, and a detached portion of the lung enclosed in a 

 cyst passing to tlie caseous state, it is difficult to see how from 

 this we can tell whether the cause is sporadic, epizootic, or 

 contagious. 



But we can tell whether it belongs to the same species of 

 disease, and sliould we find the kidneys affected and not the 

 lungs, it would be a fair presumption that the diseases did not 

 belong to the same family, and that probably they were not 

 related. 



Then from what data can we judge whether tliis be a spo- 

 radic, epizootic, or contagious disease ? By its history, and then 

 proving by a careful comparison of its pathological appearances, 

 that the different herds were affected by the same disease. 



We find that on the first of June, 1869, four sick cows arrived 

 from Rotterdam, where the disease is said to prevail. These 

 were so ill that it was necessary to carry them on trucks to 

 the farm of W. W. Chenery, of Belmont, where they were 

 introduced into his herd of healthy cattle. 



Three of these Dutch cows afterwards died. Then the origi- 

 nal herd began to show signs of disease, and one animal after 

 another was attacked, and by January, twenty-seven out of 

 sixty-seven had died, leaving a very large proportion of the 

 others diseased. 



About the first of July, three half-breed Dutch calves from 

 Mr. Chenery's farm, started for North Brookfield. One of 

 them was introduced, sick, into Leonard Stoddard's barn, and 

 after lingering three or four weeks, it died, having mingled 

 four days freely with Leonard Stoddard's herd, when it was 

 taken back to Curtis Stoddard's. In twenty-eight days after 

 the entrance of this calf into Leonard Stoddard's healthy 

 herd, a cow was attacked, and in a few days died. Other 

 cases followed each other in rapid succession, imtil thirteen 

 out of forty-eight died previous to April 11th, 1860. 



Then Leonard Stoddard sold a pair of oxen to Alden 01m- 

 stead on the 28th of November, (these oxen were afterwards 



