RELATION OF BOVINE TO HUMAN TUBERCULOSIS. 
595 
ness or moisture, constantly prevails, for we find that the 
disease is prevalent in various sections from the torrid to the 
frigid zones. 
Again, altitude, while it has in most places a marked in¬ 
fluence on the progress of the disease, has but little influence 
upon the distribution of it, as is shown in the fact that certain 
peoples inhabiting the Dead Sea basin, which is between ioo 
and 200 feet below the sea level, are free from tuberculosis ; 
whereas, it is more or less prevalent among most people inhabit¬ 
ing the mountainous regions of Europe and America. 
Civilization is not a constant factor in the distribution of 
this disease, for some of the savage and semi-civilized peoples 
are seriously afflicted with tuberculosis. 
Other things being equal, we find the disease more preva¬ 
lent the denser the population, but density of population is not 
a constant factor in the distribution of this disease, for we find 
that the masses of the people of China and India, two of the 
most densely populated countries of the world, are compara¬ 
tively free from tuberculosis, whereas the disease is quite preva¬ 
lent among the farmers of Europe and America. 
Filth and poor sanitation have a marked influence in has¬ 
tening the development of the morbid processes, but they are 
not constant factors and exert but little influence upon the dis¬ 
tribution of the disease, for we find it all the way from the 
wigwam to the palace. 
Thus we find that while the various conditions of climate, 
altitude, sanitation, etc., exert more or less influence upon the 
development of the morbid processes, they have but little in¬ 
fluence upon the distribution of the disease. 
Perhaps you are saying that tuberculosis is so widespread 
and is prevalent under such diverse conditions that there are 
not and cannot be any constantly associated factors in its dis¬ 
tribution. 
Nevertheless, a careful study of the geographical distribu¬ 
tion of tuberculosis reveals the fact that all peoples who use 
the milk and flesh of the domestic cow (the in and in-bred cow) 
