166 THE DISEASES AND DISORDERS OF THE OX. 



in most intimate correspondence with all those various involved 

 conditions to which man's intellectual powers have been, and are 

 being, subjected, furnishes in itself one of the very best of all 

 those innumerable examples which we can adduce in illustration 

 of the general process of evolution. With exceptional force does 

 this statement apply to the science of comparative pathology, a 

 science even yet in its earliest infancy. Indeed it is only most 

 recently that the gradually increasing firmness of the establish- 

 ment of the doctrine of evolution as a relatively true, real and 

 indispensable, fundamental basis of thought and fact, has led men 

 to inaugurate their initial attempts to unravel by its aid the in 

 tricate clues to the varied and at first sight most mysterious 

 phenomena of disease. The discovery of modern microscopic 

 methods has concurred to help the tide of progress in medicine 

 to a marvellous and well-nigh incredible extent. Indeed, in the 

 field of pathology, the advances made during this present century 

 now about to close, have been truly wonderful in magnitude and 

 far-reaching importance. Yet wondrous and great as they have 

 indubitably been, these discoveries are probably almost as 

 nothing when compared with the new developments of our 

 knowledge which we may expect to be made ere long. 



Probably the most important epoch of all epochs, so far as 

 the world of medicine is concerned, may be said to be this pre- 

 sent one, which has been marked by the promulgation of the 

 germ theory of disease, and by its subsequent elaboration which 

 still proceeds, and will continue to proceed with yet more rapid 

 strides. Indeed, it would be quite impossible to exaggerate the 

 importance of the influence exerted by recent discoveries, both 

 in reference to preventive medicine and to our knowledge of the 

 best modes of treating the different disorders witli which all 

 human beings and animals are liable to be affected. 



Day follows day, the years roll on, and as the wheel of time 

 revolves, it brings with it more and still more accurate informa- 

 tion, which is furnishing an entirely new basis for the sciences 

 of medicine and surgery as pursued by our predecessors. 



The discovery of the power for good of vaccination, the recent 

 establishment of the germ-theory of disease, and of its numerous 

 and weighty implications in regard to actual treatment, the em- 

 ployment of antiseptic measures, the inoculatory methods which 

 have proved so highly successful in the hands of M. Pasteur, 



