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enough; in other cases it may seem neutral, or even negative; 

 but I feel assured that the more attention is directed to the 

 systematic and painstaking accumulation of facts, the more 

 will the positive and confirmatory evidence increase, and the 

 more plainly will it be revealed that, as our bodies and minds 

 are dependent upon heredity, so also does a predisposition to- 

 the diseases of both depend upon this great law of our being. 



Diseases of the Locomotive Apparatus. In this group are 

 included the rheumatic affections of the joints and muscles ; 

 also those other disorders generally associated more or less 

 with rheumatism gout, arthritis deformans, rickets, and 

 mollities ossium. 1 



In considering the influence of heredity on this group of 

 diseases, I shall at once refer to that feverish constitutional 

 malady known as acute rheumatism (polyarthritis rheumatica 

 acuta) without staying to discuss how the progress of morbid 

 anatomy, and the comparative perfection of our diagnostic 

 methods, in these latter days, have restricted the domain of 

 ancient "rheumatism" a term which once denoted far 

 more than it does now. I think I need have no hesitation 

 in stating that a predisposition to acute rheumatism is 

 distinctly and emphatically hereditary, and that it tends to 

 run in families : indeed, some recent observations on the 

 transmission of a predisposition to this affection, by Fuller, 

 Lebert, Picot, and other authorities, prove incontestable 

 that the inheritance of such a predisposition is of very 

 frequent if not of invariable occurrence, in those cases 

 which are not acquired. In the case of rheumatism, this 

 inheritance, says Maclagan, seldom declares itself before 

 fifteen, and is generally lost again after fifty. What is trans- 

 mitted is not the disease, but a tendency to it a greater or 

 1 Ziemssen, vol. xvi. 



