deeply under the influence of chloral and its right carotid artery was* 

 exposed. Fifteen cc. of suspension of 180 mg. of live bovine tubercle, 

 bacilli, which had been washed, dried and ground in a revolving flask 

 for one hour before the addition of normal salt solution, was intro- 

 duced through a needle into the artery. Blood was withdrawn from 

 the jugular vein of the same side, but from a point distant from the 

 operation wound, twenty-five minutes, one and one-half hours, two 

 days, and six days after the inoculation. The blood drawn twenty- 

 five minutes after the introduction of the organisms showed tubercle 

 bacilli as follows : 



A search of seventy minutes in the specimen from the centrifugal- 

 ized and laked blood showed five clumps, one group of four, one 

 group of two, and one single bacillus. 



A search of fifty-five minutes in the first preparation from the top 

 layer (decolorized by rosolic solution) showed two clumps. 



A search of sixty minutes in the second preparation from the top 

 layer (decolorized by nitric acid) showed one clump. 



Both smears from the bottom of the sediment (one decolorized by 

 rosolic and one by nitric acid) showed no bacilli after sixty-six and 

 seventy-two minutes' search. 



No tubercle bacilli were found in specimens from the bleedings 

 made from one and one-half hours to six days after inoculation. 



Half of a mixture of the sediments drawn twenty-five minutes and 

 an hour and a half after inoculation was inoculated intraperitoneally 

 into a guinea pig. Ten and one-half weeks later the guinea pig was 

 killed. Three tubercles 2 mm. in diameter were found in the spleen. 

 No other lesions were discovered. 



A guinea pig was inoculated intraperitoneally with the combined 

 sediments of the blood specimens drawn two and six days after inoc- 

 ulation. The animal died six weeks after receiving the blood. Autopsy 

 showed the presence of three full-term fetuses, but no lesions of 

 tuberculosis. The results of the guinea-pig inoculation in this case 

 confirmed the miscroscopic findings. The natural conclusion would 

 be that the abundant tubercle bacilli had been rapidly filtered from 

 the blood. 



The temperature of cow 3 dropped for two hours after inoculation 

 and then rose rapidly to 106. The temperature soon fell slightly and 

 then slowly developed a marked daily variation. This animal had 

 been running an irregular elevated temperature before the experi- 

 ment. Death resulted five weeks after inoculation from hemorrhage 

 from a ruptured aneurism at the point of inoculation in the carotid. 

 Autopsy showed many hard tubercles averaging 0.5 cm. in diameter 

 scattered throughout both lungs. One small tubercle was seen in the 

 right kidney and one in the tissues near the aneurism. The medi- 

 astinal lymph-nodes were calcareous and the post-pharyngeal nodes 

 were purulent. Most of the lesions appeared to have been of long 

 duration, and autopsy gave no evidence of acute miliary tuberculosis. 



The experiments just described show that artificially introduced 

 tubercle bacilli are rapidly removed from the circulation of healthy 

 and of tuberculous cattle. That the capillaries of the lungs are more 

 efficient as filters than the capillaries of the peripheral circulation is 

 suggested by the almost complete, if not entire, absence of tubercle 



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