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affecting body and mind in health and disease, so that 

 every record of disease in a parent's life-history is stamped 

 indelibly on the tissues of his child. Let me not, however, 

 be misunderstood ; I do not mean that the diseases of the 

 parents are handed down in every case as entities to their 

 children, but that the textural or dynamical peculiarities of 

 parents, whether inherited or acquired, will undoubtedly 

 be reproduced, in varying proportions, and subject to 

 certain modifications, in their children, as, at least, predis- 

 positions to the same. This is very mysterious ; and 

 although we cannot understand or explain the processes by 

 which such effects are caused, we must, as the result of 

 observation and experience, accept the fact that, as surely 

 as a child resembles his parent or parents in his or their 

 external configuration, so assuredly does the resemblance 

 extend to his internal textures and organs, and even to a 

 predisposition to the same morbid processes from which 

 they may have suffered, and which he has inherited from 

 them. 



Pulmonary Phthisis. Of the diseases of the respiratory 

 organs none, perhaps, is more dire in its effects, or more 

 unquestionably hereditary, than pulmonary phthisis or 

 consumption, which has been known to exist contem- 

 poraneously with the sources of our historical information, 

 and to which, according to Hirsch, probably two-sevenths 

 of all deaths are now due. Without entering into a dis- 

 cussion of the various pathological theories which have 

 been broached from time to time as to the real nature of 

 tubercle, I shall content myself by observing that there is 

 a correlation, however imperfectly understood, between the 

 scrofulous and tubercular diatheses, and that while both 

 are markedly hereditary, the tubercular diathesis is met 



