TUBERCULAR DISEASE. 209 



so to speak are specially liable to the attack of 

 all other disease germs as well as that of tubercle ; 

 or, if not specially liable, they are, at least, less 

 capable of resistance when they are attacked. Still 

 it must be recognised that the tubercle bacillus has 

 a special affinity for the tissues of those wanting in 

 vital force. Some disease germs appear to attack 

 the robust and the feeble with equal frequency and 

 virulence ; others, as that of typhoid fever, seem 

 actually to prefer the tissues of the physically well- 

 to-do, but the tubercle bacillus has a decided pre- 

 ference for those bankrupt in vital energy from any 

 cause, except perhaps senility. 



I would put it in this way : The tubercle bacil- 

 lus being almost ubiquitous, so soon as the system 

 reaches a certain level of vital depravity, which I 

 would call " the tubercular level," the individual 

 becomes liable to the attack of the bacillus. In some 

 cases, small-pox, syphilis, or other exhausting disease, 

 leaves the system for a time in an impoverished 

 state, and before the vitality is restored, tubercular 

 disease is set up ; in a host of others, starvation, dirt, 

 habitual drunkenness, and want of fresh air reduce 

 the system to the level of susceptibility with like 

 result; but in the vast majority who develop tuber- 

 cular disease, the protective vital level has never been 

 reached, a wretched parentage being unable to confer 

 so much. Such individuals are from the moment 

 of conception helpless against the attack of the 

 tubercle bacillus, and succumb on first contact with 



