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Bacteriology 



BACTERIOLOGY 



Bacteria are single celled vegetable organisms, round, cork screw 

 or oblong in shape. Bacteria have power of movement but are classed 

 as plants by most biologists because they multiply by division of the 

 cell into two parts each of which makes separate bacteria capable of 

 reproduction. 



No bacteria are visible except by the aid of a microscope capable of 

 magnifying their size many hundred times. 



Varo, who lived about the time of Christ, conceived of the idea 

 that possibly some diseases were caused by invisible organisms but no 

 particular attention was given the subject till about the beginning of the 

 seventeenth century when some one perfected a lens that would magnify 

 one hundred and fifty times and living organisms were discovered in 

 what was considered pure water. 



However these organisms which they saw were not bacteria, but led 

 up to the perfection of a good microscope which enabled Pasteur, Koch, 

 Kohn and others about 1865 to 1870 to establish firmly the fact that 

 bacteria or their products are the cause of many diseases. Their find- 

 ings have cleared away many of the mysteries that once made veterinary 

 medicine a dark field. 



The germs causing hog cholrea are not present in glanders of horses 

 neither are the germs causing distemper of horses to be found in hogs 

 that die with pneumonia. That is to say the fact is well established that 

 for specific diseases certain bacteria or groups of bacteria are always 

 present. 



The presence of these bacteria is not supposed to cause the sickness, 

 but the waste products which bacteria throw off from their bodies cause? 



