^560 THE PRACTICE OF VETERINARY MEDICINE. 



with a degree of certainty that would place its origin beyond 

 the question of a reasonable doubt, but it is needless to say 

 that these efforts have been in every instance unavailing ; 

 for as soon as one authority advanced a theory apparently 

 accounting for its development, he would be answered by an 

 equally eminent authority, who would direct his efforts to 

 controverting and denying in toto the conclusions reached, 

 and who would adduce powerful arguments in support of his 

 denial, and then, having accomplished his purpose, would 

 proceed to form a theory of his own to give to the world, 

 which would, in its turn, be obliged to pass through the 

 scathing fire of criticism, and, unable to stand the ordeal, 

 emerge henceforth to be regarded as a fallacy. 



The most eminent authorities on both human and 

 veterinary diseases have disagreed and been divided in 

 their opinions on this subject : what a hopeless task, then, 

 w^ould it be for me, with my limited experience, to attempt 

 to lift the veil of obscurity under which the origin of this 

 disease is hidden, when the ablest investigators the world 

 has ever seen, both in the past and present, have failed to 

 do so. We know that influenza, like every other disease, 

 must have an origin, or it would not exist, but beyond this 

 point all is conjecture. I will now proceed to direct your 

 attention to a few of the theories held regarding the primary 

 cause or origin of influenza. It has been attributed to ex- 

 halations from the earth, but that this cannot be the cause 

 is evident from the fact that it has frequently manifested 

 itself in the midst of the ocean, where such exhalations 

 would not be likely to reach. 



Currents of electricity in the air have by some been sup- 

 posed to exert some peculiar and occult influence by means 

 of which influenza could be originated. But as no such 

 condition has ever been shown to exist in the air in con- 

 nection with the disorder, this idea is, to say the least, a 



