496 



MICRO-ORGANISMS IN DISEASE. 



Without entering into the technical details 

 of the subject, it may be said that no micro- 

 scopic work requires such extreme care as the 

 preparation and recognition of these minute 

 organisms. When removed from the body 

 they are transferred to certain " culture fluids" 

 (generally meat-broth or gelatine), where they 

 are kept alive and multiply at a temperature 

 of from 86-106 Fahr. Many precautions are 

 taken to avoid contamination from contact 

 with the air, the ordinary one being to keep 

 the fluids in glass tubes, the ends of which 

 are plugged with fine cotton or wool. 



In order to detect such minute bodies in the 

 midst of tissues, advantage is taken of their 



Eroperty of staining readily with various ani- 

 ne dyes, which are not so easily held by the 

 surrounding tissues. It is a common mistake 

 to suppose that micro-organisms are easily 

 seen; on the contrary, their detection requires 

 a practiced eye and the use of high powers. 



Mieroeoeei. These are small points or specks, 

 which are seen in the midst of decomposing 

 organic matter; in fact, their presence .is in- 

 dicative of decay, whether they are found 

 within the dead or living body. 



There are a large number of different species, 

 which have received certain distinctive names, 

 such as the " septic " micrococci, or those that 



FROM ULCEK IN LARYNX OP A CHILD THAT DIED OB- 

 SCARLATINA. 



are associated with blood-poisoning; the "zy- 

 mogenic," which give rise to certain chemical 

 changes (as in the decomposition of urine), the 

 "pathogenic," which are regarded as the cause 

 of diseases. The term "chromogenic" is ap- 

 plied to various colored forms. Micrococci 

 are found in large numbers in abscesses as 

 the inflammation increases they afe seen to 

 invade the neighboring tissues ; but, whether 

 they stand in the relation of cause or effect to 

 the inflammatory process, is not clear. They 

 are found in the bowel in diarrhoea and ty- 

 phoid fever, and in the air-cells of the lung in 

 pneumonia. 



As so-called " specific " forms, may be men- 

 tioned ^the micrococci of small-pox, which are 

 found in the eruptive vesicles, erysipelas, diph- 

 theria, pneumonia, inflammation of the lining 

 membrane of the heart, and scarlet fever. 

 Each of these forms has certain peculiarities 

 that distinguish it from the others, and is al- 

 ways found in certain locations, as in the spu- 

 tum of pneumonia, the membrane of diph- 



theria, etc. With few exceptions, they respond 

 to the test mentioned at the beginning of this 

 article, and cause the same or a similar disease 

 when introduced into the lower animals. 



Bacteria. These are small bodies whose 

 length is several times their breadth. They 

 have the power of locomotion. They occur 

 in putrefying fluids, and have also received 



different names, according to their appear- 

 ance or supposed action. Thus, one form ia 

 concerned in the souring of milk, another causes 

 the fermentation of alcoholic fluids. But the 

 most important varieties are those that are 

 found in the blood of animals dying of septi- 

 ca3mia; according to the latest ideas, they are 

 supposed to generate a poison that is absorbed 

 into the system and gives rise to the symp- 

 toms of blood-poisoning. 



Bacilli. These derive their name from lacil- 

 lum, a staff, because of their resemblance to 

 small rods. They resemble bacteria, but are 

 more slender. Like the former bodies, they 

 may occur in long chains. Some bacilli have 

 a peculiar tail, or flagellum, which is their 

 organ of locomotion. 



A peculiar property of these organisms is, 

 that although they are killed by freezing or 

 boiling, or by immersion in certain solutions, 

 such as carbolic acid, thymol, and corrosive 

 sublimate, their spores are far more resistant. 

 This fact becomes important in considering the 

 prevention of disease by destroying its germs. 

 Not to mention the bacilli of septicasinia and 

 typhoid fever, which are not regarded as hav- 

 ing a specific character, the Bacillus malari. 





SECTION OF SMALL INTESTINE OF A MOUSE DEAD 

 SEPTICAEMIA. 



found by Klebs and Tommasi-Crudeli in the 

 blood of malarious patients, and the bacillus of 

 leprosy, special mention should be made of the 

 bacilli of anthrax, or malignant pustule, dis- 

 covered many years ago. These are long rods, 

 which multiply by division, throwing off spores 

 that develop into bacilli. These parasites may 

 be cultivated outside the body, and introduced 



