168 ON INOCULATION AS A MEANS FOE THE 



Considerable stress has been laid upon the manner of perform- 

 ing the operation, to which in many instances, no doubt, the so- 

 called effects of inoculation may be falsely ascribed. For all 

 practical purposes a simple puncture or incision of the skin is 

 amply sutiicient to ensure the absorption of " the virus," and, if 

 it be a " virus," for the production of all the characteristic 

 phenomena which are manifest of tlie actual jiroduction and 

 presence of the disease, but in a milder and more manageable 

 form, from which future immunity is to be obtained. But up to 

 the present time it remains a debateable and unsettled point 

 whether the appearances or results of the inoculation are not in 

 many cases more dependent on the violence used, the instrument 

 wounding bones and ligaments, &c., or being charged with matter 

 from putrid sources. The Continental authorities on inoculation 

 for pleuro-pneumonia maintain that the disease is actually pro- 

 duced within the system by " the virus," hut it is localised, a cir- 

 cumstance entirely arising from the artificial method employed, 

 and to this localisation of the malady the success of inoculation 

 is due; moreover, they likewise state that "no constitutional 

 effects can result from inoculation unless local morbid action is 

 iirst produced," statements which are not verified by expe- 

 rience. Professor Simonds found animals to resist the action of 

 " the virus," if the absence of local signs are to be received as 

 proof, and likewise to resist the disease itself, although such 

 animals remained with the diseased and dying. Such is also our 

 own experience, and conversely, animals previously inoculated, 

 and in whom all the local signs have been fully and satisfactorily 

 established, have contracted pleuro-pneumonia as though such 

 operation had not been performed. 



These phenomena, which have repeatedly occurred, and are 

 well known to Continental and British veterinarians, have given 

 rise to a well-established doubt respecting the nature and con- 

 stitution of the fluid expressed from the lungs. Is it a " virus?" 

 As the term stands and is used in medicine, it simj)ly means a 

 morbid poison, the product of a disease, and capable of producing 

 the same disease in another animal of the same species at least, 

 by inoculation or insertion beneath the skin. How different, 

 however, are the residts of the use of the so-called " virus " of 

 pleuro-pneumonia ? It is admitted by the original promoters that 

 in no case does disease of the lungs, or, in other words, the real and 

 intrinsic signs of pleuro-pneumonia ever appear after inoculation, 

 except as a result of pyasmia or blood-poisoning. Nevertheless, 

 the disease, to all intents and pvirposes, is located in the local 

 tumefactions. The statement sets up a new theory in the science 

 and practice of medicine. Hitherto it has been sufficiently relied 

 upon that each " virus," no matter how it is introduced to the 

 system, so long as it obtains an entrance to the circulating fluid. 



