THE HISTORICAL DEVELOPMENT OF BIOLOGY 539 



which consists in injecting weak doses of the hydrophobia germs 

 into the blood of a person bitten by a mad dog. By gradually in- 

 creasing the virulence of the injections anti-toxins are built up 

 in the patient's body and resist the real attack of the disease. 

 By this treatment the mortality has been decreased from practically 

 certain death to less than one per cent. 



The world owes to Pasteur the foundation of all our modern 

 methods in bacteriology, our serum and anti-toxin treatments, 

 and all the lives that have been saved thereby. Possibly more 

 people owe their lives to the results of his work than to that of 

 any other man who ever lived. 



Other Victories over Disease. At the Pasteur Institute many 

 discoveries have been made in the line of inoculation against lock- 

 jaw (tetanus), bubonic plague and other germ diseases, but none 

 has saved more lives than the anti- toxin for diphtheria. This 

 was developed by Roux, a fellow worker with Pasteur and by 

 von Behring, a German bacteriologist in 1894. By this use a 

 disease which annually caused the death of thousands of children, 

 now has its rate reduced about 80 per cent and if treatment is 

 given early in the case, recovery is almost certain. 



Among others who have labored in the work against germ 

 disease may be mentioned Robert Koch, who studied the relation 

 of bacteria to human disease, especially in the case of tuberculosis 

 and Asiatic cholera. He was the first to identify these bacteria 

 and though he devoted his life to the work, did not discover a 

 specific cure for tuberculosis. However, his work has enabled us 

 to take preventive measures which are greatly aiding in suppres- 

 sion of this worst of the " ills that flesh is heir to." 



Antiseptic and Aseptic Surgery. Sir Joseph Lister, an English 

 surgeon, was the first to fight the germs of the operating room by 

 the use of antiseptics, such as carbolic acid. This one discovery 

 has done more to prevent death by infection after operations 

 than any other of recent times. Modern surgery aims to keep 

 its wounds aseptic, that is, free from all germs by careful methods 

 of sterilization, but still relies on anti-septics to kill any germs that 

 may have found entrance. Before Lister's time infection of op- 



