PASTEUR'S VIEWS CONFIRMED. ^ 



ii the infecting elements in these diseases, whether they be the 

 rudimentary forms of animal or vegetable life, or merely particles 

 of our own bodies which have acquired a poisonous property 

 which does not naturally belong to them, most are now agreed, I 

 think, that such particles have a veritaole existence. 



With the limited time at my disposal, I can but give you the 

 briefest account of the proofs that have recently been accumulating 

 in support of Pasteur's views, besides those of many other obser- 

 vers,* that that something by means of which infecting diseases 

 pass from one to another, has a real existence, is an organised 

 solid, however minute, which is the absolutely indispensable 

 agent in the transmissibility of these diseases. These opinions 

 mark a great advance in the medical views of the past few years. 

 The phantom of what used to be called an " epidemic constitution 

 of the atmosphere " has ceased to haunt us, while sanitary and 

 medical science are more and more mustering their resources for 

 the utter destruction of those invisible potentialities which are 

 everywhere about us, " both when we sleep and when we wake." 

 Let me illustrate what I have said by means of these diagrams. 

 You see those particles ; they are so minute as to require the aid 

 of a powerfully magnifying lens to bring them into view. They 

 are obtained by filtration from vaccine lymph, which appears to 

 our unassisted eye to be a clear fluid. If the lymph without the 

 particles be used to vaccinate, it entirely fails ; but if the particles 

 be used without the fluid, it perfectly succeeds. You will better 

 understand what I mean when I tell you that a person undergoing 

 vaccination, is passing through a mild or modified form of small- 

 pox. These particles may be therefore regarded as the virtual 

 agents in the production of small-pox. Similar particles per- 

 fectly alike in outward form exist in the lymph of Glanders or 

 Farcy, a most virulent disease which attacks horses, but is com- 

 municable to man. A horse inoculated with the fluid, without the 

 particles, would escape, but not if it contained the particles. 

 In this other diagram you have a view of infecting germs derived 

 * Obermeyer, Kleba, Chaveau, Burden Sanderson, Lister, Greenfield 



