The Avenues of Infection 87 



the intestine is responsible - for a condition of sub-infection 

 depending upon the constant entrance of colon bacilla into 

 the blood. He finds the colon bacillus in the blood, and 

 traces it to the liver, where its final dissolution takes place 

 in the fine dumbbell-like granules enclosed in the cells,. 

 Nicholls* confirms Adami by finding similar dumbbell or 

 diplococcoid bodies in the epithelial denuded tissues of the 

 mesentery of normal animals. 



Nicholas and Descosf and RavenelJ fed fasting dogs upon 

 a soup containing quantities of tubercle bacilli, killed them 

 three hours later, and examined the contents of the thoracic 

 duct, where tubercle bacilli, some alive and some dead, were 

 found in large numbers, van Steenberghe and Grysez 

 found that carbon particles readily passed through the 

 intestinal mucosa, entered the lymphatics, were thrown 

 into the venous circulation, and so carried to the lung, where 

 anthracosis was produced. 



In a subsequent paper || they believe that they have demon- 

 strated that the tubercle bacillus like the carbon particles 

 may also pass through the normal intestinal wall, and follow 

 the same course to the lungs. They believe that pulmonary 

 tuberculosis thus depends upon ingested and not inhaled 

 micro-organisms. At my suggestion Montgomery** en- 

 deavored to repeat the work of van Steenberghe and Grysez 

 at the Henry Phipps Institute, Philadelphia, but though 

 many attempts were made by various methods, no carbon 

 particles were transported from the alimentary to the pul- 

 monary tissues. 



But there are enough experiments recorded to make it 

 probable that the wall of the intestine is permeable to bacteria, 

 and that in small numbers they constantly enter the blood of 

 healthy animals, to be disposed of by mechanisms yet to be 

 described. 



Many of the bacteria penetrating the intestine must be 

 retained in the lymph nodes; others, as in the experiment 

 with the tubercle bacilli, meet destruction before they reach 

 the blood; the remainder must reach the blood alive. 



* "Jour. Med. Research.," vol. xi, No. 2. 

 t "Jour, de Phys. et Path, gen.," 1902, iv, 910-912. 

 I "Jour. Med. Research." x, p. 460, 1904. 



"Ann. de 1'Inst. Pasteur," Tome xix, No. 12, p. 787, Dec. 25, 1905. 

 || Ibid., 1910, xxiv, 316. 

 ** "Jour, of Med. Research," Aug., 1910, vol. xxm, No. i. 



