42 RELATION OF THE DISEASE 



any degree of integrity is the starch, whilst we find the 

 gluten in a state of utter decomposition, the amylaceous 

 fibre disorganized, a little sugar formed, and a new sub- 

 stance generated, which I shall hereafter describe. 



(162.) Looking at the malady with a political eye, we 

 have seen in the diseased potatoes some useful matter 

 mixed with abundance of putrid useless substance. 



CHAPTER VI. 



RELATION OF THE DISEASE TO INTERNAL CAUSES. 



Gangrene from old age (104). Kinds not equally affected (165). 

 Progress of disease in Chelsea wild plant (166) ; in Uhde's plant 

 (167) ; in various varieties (168) ; in plants requiring much leaf 

 (170). Horticultural Society's plant (172). Greatrex's account 

 (175). Storr's account (176). Latham's account (177). Early 

 varieties less liable to disease (179). 



(163.) IT is difficult to imagine how any organic body 

 should produce within itself means for its own destruction ; 

 yet we perceive in our own bodies that man gets old, his 

 organs no longer perform their functions, he ceases to live, 

 and is gathered to his fathers. 



(164.) A theory has been started, that the potatoe, being 

 but a variety, has had its career ; that the plant has be- 

 come old, and is now dying. Facts, however, do not bear 

 out this assertion, for I have see this year's seedlings as 

 much diseased as the oldest variety. The malady has 

 paid no respect to youth or to age, but has cut down pota- 

 toe plants in all periods of their existence. 



