SO UKCES OF INFECTION. 33 



much larger than that for the lungs. The bacteria used were 

 those of anthrax, with their spores, and those of chicken cholera 

 and septicaBmia. Irritation of the bronchial mucous membrane 

 retarded the ingress of microbes into the circulation. When large 

 quantities of bacilli were used the irritation was often so great 

 that a hemorrhagic pneumonia resulted. The best results were 

 obtained by using only the spores, after destroying the bacilli by 

 drying. The growth of bacilli was very rapid, and in a short 

 time the microbe could be found in the pulmonary capillaries. 

 The rapidity with which the microbes entered the pulmonary 

 tissue was proof positive that a more direct tolerance was effected 

 than through the lymphatics. The author is of the opinion that 

 the chemical irritation exerted on the walls of the capillaries 

 causes the formation of stomata, through which the bacilli grow. 

 These experiments demonstrate also, that the blood microbes are 

 best adapted to pass through the pulmonary tissues into the circu- 

 lation. The microbes of anthrax, recurrent fever, and malaria are 

 the most striking examples of the blood parasites so far known. 

 In infection caused by blood microbes, the point of entrance can- 

 not always be found, as they may enter through apparently intact 

 surfaces. Even in the case of microbes not strictly blood micro- 

 organisms, it is possible for them to penetrate the pulmonary capil- 

 laries and be transported to that part of the body where they 

 afterward initiate morbid conditions. These experiments show 

 conclusively that pathogenic microbes suspended in the atmospheric 

 air can enter the organism through the respiratory organs. 



Petri (" Zusammenfasseuder Bericht iiber Nachweis und Bestim- 

 intmg der pflanzlichen Microorganismen in der Luft," Centralblatt 

 f. Bacteriologie u. Parasitenkunde, B. ii. Hefte 5 u. 6) claims that 

 the methods so far employed in the detection of pathogenic germs 

 in the air have not succeeded in demonstrating more than the 

 microbes of pus, a circumstance which may be ascribed to the 

 methods employed, as some pathogenic germs do not grow upon 

 gelatin at ordinary room temperature, and that the culture of the 

 microbe sought for may become obscured by cultures of other 

 microbes. 



Emmerich (" Ueber den Nachweis von Erysipelkokken in einem 

 Secirsaale," Deutsche m,ed. Wochenschrift, 1877, No. 3) by means ot 

 an aspiration apparatus obtained air from an old dissecting-room, 

 which for a long time had not contained any erysipelatous material, 

 and cultivated from it the cocci of erysipelas, which on being inocu- 

 lated into animals produced typical erysipelas. The cocci were also 

 found in shavings of the floor and in the plastering of the walls 

 and ceilings. 



Eiselsberg (" Nachweis von Erysipelkokken in der Luft chirur- 



3 



