PLEURO-PNEUMONIA. 545 
or sending the carcasses of the affected animals to convenient 
depots, and consigning the live animals to public sales or 
markets, and in this way scattering the disease broadcast 
through the country. 
Will Plenro always be with us ? 
And what of the cry as to the perpetual existence of the 
disease amongst us? You and I, Mr. President, were not 
alive a century and a half ago—probably neither of us recol¬ 
lect distinctly the occurrences of half a century since, even— 
but it is nevertheless a matter of history, that for one hun¬ 
dred years prior to 1842, pleuro-pneumonia was a stranger to 
this country ; and looking back over the past quarter of a 
century, I can see in my mind’s eye counties and districts 
free that were at one time hot-beds of the scourge. Even in 
this very city there has been a period of two years of abso¬ 
lute freedom from the disease since I have been dealing with 
it in an official capacity. 
In Holland, Switzerland, Norway, Sweden, Denmark, and 
in many of the North American States, it is no more known ; 
and in face of these facts, what right have we, I ask, to adopt 
the pessimistic view that pleuro-pneumonia is always to be a 
scourge to our herds. Periodical epizootic waves of this, as of 
all other similar maladies, have swept over our country, but 
there cannot be any periodicity of such epizootic waves if we 
take the trouble to annihilate the essential element upon which 
they depend. There were some who prophesied that when 
foot and mouth disease was suppressed we should be visited 
by a periodical epizootic in due course. Well, we have waited 
for years for this recurrence, and it has not yet put in an ap¬ 
pearance. 
No Spontaneous Pleuro-pneumonia. 
The doctrine of periodicity had a worthy congener in the 
doctrine of spontaneity. Life cannot be brought into existence 
by fortuitous influences, and if we believe, as we are bound 
to believe, and as all analogy teaches us, that pleuro-pneumo¬ 
nia is due to a specific germ, then are we further bound to 
discard the notion that the disease can be induced by any 
