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stock, for a generation, but never lost A predisposition to 

 degenerative diseases of the kidney is therefore as much 

 a fact as that scrofula or phthisis are the results of the 

 development of a pre-existing disposition in the organs or 

 tissues affected by them. The three degenerative diseases 

 of the kidney known under the generic name of Bright's 

 disease will afford an example. The first, or inflammatory 

 form, may be acute or chronic, and usually affects the 

 tubules; the second, or waxy, lardaceous, amyloid or 

 albuminoid is degenerative, and originates usually in the 

 vessels ; whilst the third, the gouty or cirrhotic form, is 

 also degenerative, and originates in the fibrous stroma. 

 What has heredity to do with these conditions ? Let us seek 

 our reply in the etiological sources of each of these 

 affections. The inflammatory affection is said to be caused 

 by exposure to cold, and by scarlatinal and other blood- 

 poisons : the latter I shall consider presently, when I come 

 to deal with heredity as affecting the acute infectious 

 diseases. With regard to exposure to cold, we have already 

 seen that the catarrhal diathesis is universal, but may be, 

 and is, differently distributed in different individuals. Let 

 us suppose, for example, that a parent has in early life 

 suffered from this inflammatory affection of the kidneys, 

 however caused : however competent to discharge their 

 functions afterwards, the kidneys during his life will bear 

 the brand of what they have suffered they will be somehow 

 different from what they were originally. This parent has 

 a child or children who have, in common with humanity, 

 inherited the catarrhal diathesis, subject in his or their 

 cases to the combined catarrhal predisposition of both 

 father and mother. From what we have already seen of 

 the action of heredity, is it too much to assume that one of 



