no 



individuals affected. These differences, so marked even 

 amongst the children of the same parents, are naturally 

 more obvious amongst those having no kinship, as in the 

 case of unrelated individuals attacked by any of the diseases 

 named, or by erysipelas, pleurisy, pneumonia, acute rheu- 

 matism, bronchitis, influenza, or any other acute or chronic 

 disease ; we all recognise the differences every day of our 

 lives, but how comparatively few of the rank and file of the 

 profession regard them in their true light, and as dependent 

 upon the differences existing between man and man, in con- 

 sequence of the action and interaction of hereditary and 

 acquired influences. If we regard diseases as so many 

 entities of which we may all partake in different quantities, 

 and not as particular conditions new phases of the vital 

 manifestations of the living body, whether of the nature of 

 functional derangements, or organic or textural degeneracy 

 and which owe the differences of their symptoms, develop- 

 ment, intensity, and modes of termination to the inherited 

 and acquired constitutional differences existing between man 

 and man, we shall not only be following wrong principles in 

 practice, but prove unworthy of the trust committed to our 

 care the health and well-being of our fellow men. 



It must not, however, be understood or supposed that 

 I am anxious to try to prove that all diseases are alike 

 hereditary ; but it does seem to me but a natural sequence, 

 if we admit that, as I have indicated, every individual is 

 subject to heredity in his physical, mental, and moral con- 

 stitution, and to such an extent in his physical organisation 

 that the minutest structure of his every organ and tissue, is 

 characterised by it; that the life-history of his parents' 

 organs and tissues will be re-enacted, to some extent, at 

 least, in his own ; and that when they have developed 



