6 DEPARTMENT OF AGRICULTURE. 



more 



the nature of many forms of specific virus, but actually constitute the eontagium or 

 active principle which breeds and propagates in the development of small-pox, cholera, 

 the plagues of the lower animals, (fee. There is one grave objection to all that has yet 

 been done in this interesting field of inquiry. The vegetable forms into which poisons are 

 said to pullulate have not, in a single instance, been successfully employed in the repro 

 duction of the diseases they have been supposed to generate. 



Delafond* quotes Aristotle, who wrote his work on the History of Animals three 

 hundred and fifty-four years before Christ, to prove that cattle were then known to suffer 

 from a disease of the lungs. &quot;The cattle,&quot; he says, &quot;which live in herds are subject to 

 a malady, during which the breathing becomes hot and frequent. The ears droop, and 

 they cannot eat: They die rapidly, and on opening them the lungs are found spoiled.&quot; 



In the collection of extracts and writings of the Greek veterinarians, made by order 

 of the Emperor Constantine, descriptions of the lung diseases of cattle are given which 

 may lead us to infer the prevalence even then of the lung plague.f 



It would be simply waste of time to discuss the merits of unsatisfactory hints for 

 they are not records which have been traced in the writings of Livy, Vegetius, Silius 

 Italicus, Columella, Virgil, and others ; hints which, no doubt, demonstrate that which 

 few will question that pulmonary disorders have existed throughout all time. 



The evidence that we need is that definite record of outbreaks of a malady marked 

 by the leading characteristics of the lung plague. We have to skip the age of pure quack 

 ery, when nothing but the unsatisfactory prescriptions of ignorant pretenders in veterinary 

 medicine were handed down as valuable additions to human knowledge. A purpose is 

 served, however, by referring to these dark ages, when, in their blindness, men sought to 

 arrest the unrelenting torrents of fierce contagions by pills, draughts, charms, and incan 

 tations. It makes one blush for the errors and superstitions which, in the Old World and 

 in the New, have prevailed up to the present hour. For seven and twenty years, at least, 

 the people of Great Britain have, in the main, favored nothing but quackery in this re 

 spect, just as much as continental nations that suffered in ignorance did in the seventeen 

 hundred years succeeding the birth of Christ. So late as 1865 the outbreak of a virulent 

 cattle plague in England developed in its train the compounders of drugs and filth, and the 

 believers in the treatment of isolated cases of a plague ; of a plague, indeed, which advances 

 in direct ratio to the delay in extinguishing its virulent poison, and the rapidity of whose 

 spread may be likened to that of the confluent mountain waters that form the inland seas and 

 navigable streams. Let the people learn from the ancient history of veterinary medicine, as 

 they can learn from recent events, that to dam the Mississippi and annihilate its waters is 

 quite as easy a process as attempting to save a country from incalculable loss by the med 

 ical treatment of isolated cases of a specific and contagious cattle plague. 



That is the lesson which the want of knowledge regarding the lung plague in the first 

 seventeen hundred years of the Christian era impresses upon us to-day. The wisdom 

 of that conclusion may be demonstrated by tracing up the progress of the malady from 

 1693 to 1869. 



* Trait&amp;lt;5 sur la Maliulie &amp;lt;le Poitrine du Gros Detail, connne sous le nom de Pe ripneuinonie G outagieuse, j&amp;gt;ar O. Dela- 

 fond, Paris, 1844. 



t Gcopniiicoruiii, sen de Re Rustic*, Lib. XX edited by Peter Needhain, Cambridge, 1704 Quoted by Sauberj;. 



