342 SCIENCE PROGRESS 



seemed any the worse. About five days before bringing it to 

 the hospital, the mother had noted that though the child took the 

 breast as vigorously as ever, it vomited suddenly very soon 

 afterwards ; this sickness continued and the child became very 

 fretful, especially when disturbed ; later on it was drowsy. 

 She remarked that it was unusually constipated. The day 

 before the child was brought to hospital it was attacked by 

 severe convulsions : soon afterwards it appeared not to recognise 

 the mother and seemed unable to swallow its food. She herself 

 was in good health but her husband was suffering from phthisis, 

 A diagnosis of tuberculous meningitis was made. Despite 

 treatment, the infant became steadily worse and died a few days 

 later. At the postmortem, advanced tuberculous degeneration 

 (caseation) was found in the bifurcation gland. There were 

 large numbers of very recent, tiny miliary tuberculous 

 foci present in the lungs, brain and spleen corresponding 

 in their numerical incidence to the order given above. A 

 few tubercles were to be seen in the liver, very few in the 

 kidneys, none at all in the supra-renal nor the pancreas. In 

 the lower part of the small intestine a few very recent tiny 

 tuberculous ulcers were found. The heart showed no evidence 

 of tuberculosis ; the stomach also was unaffected. 



The evidence that miliary tuberculosis is spread by the blood 

 stream and that the tubercle bacilli do settle in blood vessels is 

 so strong that for the purposes of this article it may be accepted 

 as proven. Accepting this hypothesis, it is interesting to review 

 the course of events from the time when the infant first sustained 

 an attack from tubercle bacilli till its death. 



We may safely suppose that under the social conditions in 

 which persons of the hospital patient class live, the husband 

 shares their couch at night with wife and child. In such intimate 

 contact, the sleeping babe would inhale tubercle bacilli, as his 

 father lay wakeful and coughing through the night. It is my 

 belief, founded on considerations that I shall presently advance, 

 that tubercle bacilli so inhaled do not, in children at least, lodge 

 in the upper air passages in sufficient numbers to give rise to 

 lesions there but that they pass down the windpipe and are 

 carried along with the strong inspiratory air blast directly into 

 the ultimate air-cells of the lungs. Such is the known course 

 taken by bacilli or dust particles when injected into the trachea 

 under experimental conditions. 



