History of Influenza. 59 



sphere, altering its relations to the living body. 

 I will give you my reasons for these conclusions. 

 If the epizootic was propagated through the 

 medium of respiration, the tissues which had 

 come first in contact with the poison or irritant 

 in its unspent or undiluted form would, as a 

 matter of course, suffer the most. If a horse or 

 a man takes an irritant poison, of which he dies, 

 what do we find ? Why, intense inflammation of 

 the mucous membranes of the stomach and bowels. 

 If a horse or man is half- suffocated in the fumes 

 of dense smoke, so that in a few days he dies, 

 what do we find ? Why, intense inflammation of 

 the mucous membranes of the air passages, and 

 congestion of the lungs ; in either case we find 

 that the very tissues which have come into direct 

 actual contact with the irritant are most severely 

 affected. So should we find it in influenza if it 

 was caused by some irritant or morbific poison in 

 the air. But what does post-mortem examination 

 of true influenza cases prove to us ? They show 

 us unmistakeably that fine delicate membranes in 

 the air-cells are nearly always perfectly free from 

 disease. Frequently we find these tissues in a 

 state the very reverse of congestion, inflammation, 

 or tumefaction. They are of a lighter colour, are 

 less in weight, less in bulk, than when in health, 

 and even in those cases where we have hydro- 

 thorax hydrops pericardii^ this has not been pre- 

 ceded by the slightest inflammatory action it has 

 exhaled out of the surfaces and not exuded. I 

 look upon these as almost, if not quite, proof 

 positive that it is not attributable to a morbific 



