544 
introduced into the healthy intestinal canal of animals rapidly passed 
through the uninjured mucosa and appeared in the great thoracic 
duct on their way to the venous circulation. Xocard and his pupils, 
Desoubry and Porcher,® had earlier shown that the passage of bac- 
teria through the normal intestinal wall and their transference to the 
blood was possible. Chavreau, * & in view of the constantly accumulat- 
ing evidence that pulmonary tuberculosis in man and animals arises 
from infection through the intestine, calls attention to his investiga- 
tions from 1868 to 1874. in which pulmonary tuberculosis was brought 
about by the ingestion of tuberculous material without the production 
of pathological conditions in the digestive tract. 
This earlier work was followed rapidly by other investigations, 
which proved more and more conclusively that the introduction of 
tubercle bacilli into the body with food may lead directly to the 
development of pulmonary tuberculosis, without lesions in the ali- 
mentary canal and without intermediate lesions of disease between 
the digestive and respiratory organs. The most important investiga- 
tions are probably those of Calmette and his associates, now pub- 
lished in book form. 0 
These investigators claim, and present good evidence in support of 
their claim, that dust particles never penetrate deeper into the lung 
than to the first bandies of the bronchi : that tuberculosis is constantly 
a disease of which the infection enters through the intestine; that 
tubercle bacilli may penetrate the intestinal wall without causing 
lesions ; that the bacilli may pass through the mesenteric glands with- 
out causing lesions ; that the bacilli frequently cause primary lesions 
in the mesenteric glands of young experiment animals, but commonly 
pass through these glands of adult animals and cause primary pul- 
monary tuberculosis; that tuberculous processes in the lung never 
begin in the bronchi or alveoli, but constantly in the capillaries, 
especially in the finest capillary network of the subpleural tissue, etc. 
Kelative to this localization of the earliest stages of pulmonary 
tuberculosis, Aufrecht d says : 
Tlie initial changes in the apices of the lung, as I hare convinced myself by 
repeated anatomical examinations, do not spread from the terminal branches 
of the bronchi. 
° Comp. Rend. Soc. de Biologie. Yol. XL VII, 1895. 
6 Experiment Station Record. U. S. Dept, of Agriculture, Yol. XIX, Xo. 2, 
1907. (Comp. Rend. Acad. Sci., Xo. 15, Paris, 1907.) 
c Reeherches experimentales sur la Tuberculose, effectuees de l'institut Pas- 
teur de Lille, par Calmette et Guerin, P. Yansteenberghe. M. Breton, Grysez. 
Sonneville et Georges Petit, Paris, 1907. Reviewed in the monthly publication 
of the International Antituberculosis Association, Tuberculosis, Yol. YI, Xo. 5, 
1907, pp. 256-259; also in Zeitschrift fur Tuberkulose, Yol. XI, Xo. 2, 1907, pp. 
163-166. 
d Berliner Klinische Wochens., Xo, 27. 1907. 
