Biological Papers. 141 



TUBERCULOSIS. 



By Dr. Burton R. Rogers, Agricultural College, Manhattan. 



1 N all civilized countries there is a preventable disease which 

 ^ has been and is the cause, and the only cause, of the death 

 of ten per cent, of our people. If we knew no more concerning 

 the white man's plague to-day than we did prior to 1880, nine 

 million of the ninety million people living in this country to-day 

 would die of this disease. If we do not grasp and profit by the 

 facts we know to-day the same will be true in the future. 



But the most magnificent and most beautiful star in the 

 medical and scientific firmament of to-day is that this disease 

 is preventable and largely curable. 



The only direct cause of tuberculosis is the entrance of the 

 tuberculosis germ into a living body. Tuberculosis is abso- 

 lutely impossible without the germ, as a corn-field is impos- 

 sible without seeds of corn. Therefore the proposition is, 

 where do the germs come from, and how may they be exter- 

 minated ? 



More than ninety-five per cent, of them come from two 

 sources, namely, from the undestroyed sputum of tuberculous 

 people and the unprepared food products of tuberculous ani- 

 mals. There are many varied opinions as to which of these 

 two sources produces the larger per cent., the majority having 

 held for a long time that the bulk of human tuberculosis is 

 due to the dried sputum of careless or ignorant tuberculous 

 people being inhaled. 



Conscientiously I cannot concur in this, for I believe Nature 

 has so constructed the air-passages that very few diseases can 

 be produced by inhalation, for it contains moist angles that 

 make a winding, rather than a direct, course for the inspired 

 and expired air. The beautiful result is that, while the volume 

 of air itself may follow a curved course, deflected here and 

 there till it reaches the air-cells of the lungs, the particles, in- 

 cluding germ life of all kinds, strike the moist angles, to which 

 they adhere. It is similar to fanning dust into two curved 

 stovepipes, one dry, the other lined by a moist cloth. 



The cilia of the cells of the respiratory mucous membrane 

 then convey them to channels through which they can be ex- 

 pelled to the exterior. Foreign material thus reaching the 



