68 Infection 



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, this 

 being the common method by which anthracosis was pro- 

 duced. 



There are enough of these experiments 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. 



The presence of colon bacilli in the greater number of the 

 organs shortly after death has led some pathologists to 

 assume that they readily pass through the intestinal walls 

 during the death agony, but although experiments have been 

 made to prove and to disprove it, the matter is still con- 

 troversial. Undoubtedly in the final dissolution some 

 change takes place in the constitution of the individual by 

 which general invasion by bacteria is made more easy than 

 under normal conditions. 



The respiratory apparatus affords admission to a few 

 micro-organisms whose activities seem more easily carried 

 on there than elsewhere. Although it is still controversial 



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



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



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



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



