20 BACTERIOLOGY 



which thus furnished me with the principle on which the 

 antiseptic system can be carried out." Again, in 1892, on the 

 occasion of Pasteur's Jubilee celebration, Lister wrote to him : 

 " Truly there does not exist in the entire world any individual 

 to whom the medical sciences owe more than they do to you. 

 Your researches on fermentation have thrown a powerful beam, 

 which has lightened the baleful darkness of surgery, and has 

 transformed the treatment of wounds from a matter of un- 

 certain and too often disastrous empiricism into a scientific 

 art of sure beneficence. Thanks to you, surgery has undergone 

 a complete revolution, which has deprived it of its terrors and 

 has extended almost without limit its efficacious power." John 

 Tyndall, the great English natural philosopher, in speaking of 

 Pasteur's work, said: "We have been scourged by invisible 

 thongs, attacked by impenetrable ambuscades, and it is only 

 to-day that the light of science is being let in upon the 

 murderous dominion of our foes." 



The next great advances in bacteriology were due to the dis- 

 coveries of the German bacteriologist, Robert Koch, who was 

 born in 1843. In 1876, he succeeded in isolating the bacillus 

 of Anthrax in pure culture as it is called, i.e. freed from the 

 presence of all other contaminating organisms. This bacterium 

 had been observed many years previously (1850) by Davaine, 

 in the blood of animals dying from the disease, but it was re- 

 served for Koch to scientifically prove that it and it alone was 

 the cause of the disease. Later, by applying the recent advances 

 made in the development of the microscope and the aniline 

 dyes, but more especially by his discovery of an easy method of 

 separating or isolating bacteria from one another in pure culture 

 by means of his solidified nutrient culture-media, he was able to 

 demonstrate and prove that Tuberculosis (1882) and Cholera 

 (1883) were due to specific bacteria which are now often spoken 

 of by his name Koch's tubercle bacillus and Koch's comma 

 bacillus of cholera. 



From this period onwards, the bacteriological era may be 

 said to come into full swing. Discovery followed upon dis- 

 covery, and the cause of one disease after another was tracked 

 and studied a work still going on all over the world in every 

 scientific laboratory and school of medicine. The cause of 

 bacterial diseases such as Typhoid Fever, Diphtheria, Pneu- 

 monia, Tetanus, and a host of others ; protozoal diseases such 

 as Malaria, Syphilis, and Sleeping Sickness, have been dis- 

 covered and the knowledge so gained has been applied to their 

 prevention and cure. Antitoxic and anti-bacterial sera, and 

 vaccines of all descriptions have been added to the doctor's 

 armamentarium for the fighting of disease and death, and it is 



