the supcrliciul examination wiiich I was able to make led me to eon- 

 elnde that nearly half of them showed traces of the disease. 



It seems from all we can learn that a cold climate is less favorable 

 to the development and propagation of tuberculosis than a warm 

 or tropical one. Veith states that the disease does not occur in 

 animals living in a wild condition, nor even in those which are in a 

 serai-savage state. Spinola confirms this statement, and adds that 

 the affection is unknown in the Russian steppes, and is rare in ele- 

 vated regions. According to Zippelius, tuberculosis is most fre- 

 quently developed in deep and narrow valleys, or in densely populated 

 localities. The disease causes the greatest ravages in damp and 

 dark dwellings with imperfect ventilation and drainage. 



IS HUMAN TUBERCULOSIS CONTAGIOUS? 



A careful research into the literature of the subject shows that 

 nearl}' all the celebrated medical writers from the earliest times 

 believed in the contagiousness of human tuberculosis, among whom 

 may be. named Aristotle, Hippocrates, Galen, Morton, Valsalva, 

 Morgagni, Riverius and many others equally noted in the annals of 

 medicine. 



About a hundred years ago. however, a reaction set in against this 

 almost universal belief, in central and northern Europe, and also 

 in America, while the old opinion still prevailed in Italy and other 

 parts of Southern Europe. Within a comparatively short time, how- 

 ever, the leading physicians of Europe and America have been chang- 

 ing back to the old opinion, and so many observations on this point 

 have been published in the medical journals during the last few years, 

 that we are forced to accept the view that the disease is really conta- 

 gious. The word contagious is used in this paper in its widest sense, 

 as -synonymous with communicable, transmissible or "catching." I 

 must leave further discussion of this question, and also whether the 

 disease is hereditary, to the medical profession ; but the following 

 cases are of so great interest in this connection that I venture to give 

 them. Eisenberg of Warsaw reports a case where tuberculous in- 

 fections followed the Jewish custom of circumcision, and the appli- 

 cation of the lips to the wound to stop the bleeding. In this case the 

 contagious matter was transferred from the lips of the operator to the 

 wound. Several other similar cases are on record. 



Tascherning reports in the Progress of Medicine for 1885, the 



