644 bourgelat’s introductory lecture. 
living brutes the sources of life and of death, has opened to us, . 
in its turn, the immense treasures it has accumulated. The 
knowledge, as perfect as it can well be, of the tissues and of the 
interior structure of the human frame, and of the use for which 
the different organs are formed; of the causes, for the most part 
concealed, of natural effects, and consequently of morbific in¬ 
fluences ; of the power and efficacy of remedies; in a w 7 ord, all 
the invaluable riches it has acquired, and for which it is in¬ 
debted to the constant and united labours of the greatest men, 
are for us so many precious discoveries, and which promise to 
our art an increase of advancement the more certain and rapid 
in proportion as we always rigorously submit the differences and 
the relations that we find to the laws of the severest reason: for 
in the fallacious course of analogy the most perfect truths are and 
have been but too often the germs of error. 
This wise caution is not less essential with regard to prac¬ 
tical facts. We ought not to admit or to apply them carelessly, 
or without their being confirmed by proofs the most undis- 
putable; proofs, the admission of which will not be followed by 
regret. This sagacity and prudence in the consideration of facts 
constitutes one of the means most proper to accelerate the pro¬ 
gress of veterinary medicine. It must nevertheless be allowed, 
that we labour under many disadvantages, compared with the 
human surgeon, in uniting and combining all that can have re¬ 
lation to the production, the nature, the course, and to the 
treatment of disease. The hereditary predispositions of a crowd 
of animals, of various species, exposed for sale, and soon dispersed 
in every direction, cannot be known to us. The particular con¬ 
stitution of each of them, their strength or weakness, according 
to which the same morbific cause producing the same ravages in 
the interior of the animal, may assume in his external form very 
different symptoms or effects, are equally concealed. We scarcely 
know more of their habits ; the qualities of their food and 
water; the nature of their work or their exercise; the time of the 
possible suspension of their excretions; their preceding diseases; 
the medicines which have been employed; the effects which 
these medicines have produced, and whether they may not have 
