[ 775 ] 



and with undesiccated marrow freshly taken out of the dead 

 rabbit, or the dead dog. 



1,334. The desiccated spinal cords are mixed up severally 

 with water in glasses before syringing the vaccines to men. 

 The inoculation is done with a Pravaz syringe, under the 

 abdominal cuticle in the case of the human subject, and into 

 the brain of lower animals for experimental purposes. 



r >335- It ma y De tri at Pasteur's method of inoculation for 

 rabies, both as a curative and also as a protective measure, 

 will be in future adopted not only in human pathology, but in 

 the pathology of our domestic animals also, which are no less 

 subject to rabies than men. 



!>336- Pathological explanation uncertain. Why this 

 method of treatment for infectious diseases (i.e., those caused 

 by lower organisms) should prove efficacious is difficult to 

 say. But analogy goes to show that it is a most natural 

 method. A person may accustom himself to taking gradually 

 larger and larger doses of arsenic until he can take such a 

 quantity without serious harm as would certainly kill one not 

 so accustomed. So with alcoholic poison, opium, and per- 

 haps all poisons. It is like a person accustoming himself 

 to lifting heavier and heavier weights, touching hot substances 

 or performing acrobatic feats. There is an almost unlimited 

 degree of tendency in animal organisms to adapt themselves 

 to the circumstances to which they are subjected if they are 

 gradually subjected to them. This tendency is shared alike 

 by the muscles, the nerves, the viscera, and, in fact, by all 

 living portions of the body. But exactly in what way custom 

 is a protection against susceptibility no one can say. It may 

 be that the particular tissues undergo a chemical alteration 

 in this process of accustoming, and the chemically altered 

 tissues are no longer acted upon injuriously by the otherwise 

 poisonous or deleterious conditions. Inoculation for infectious 

 diseases is a kind of accustoming. It is done in the case of 

 rabies at several stages ; in the case of charbon at two ; in 



