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Ear advanced before they were harvested. If the seed 

 of the disease has first reached the tubers, no doubt it 

 will be developed into rottenness after lifting and storing, 

 but not otherwise. Therefore the only chance of saving 

 the bulk of the Potato crop is to harvest all that are fit and 

 all that are in danger at once. Fortunately for the practi- 

 cability of the course I am advocating the two terms are 

 well nigh convertible. Potatos are fit to eat, almost fit to 

 keep, before they are in much danger from disease. The 

 Peronospora makes little progress until the plants approach 

 maturity. Of course, these assertions are meant to be un- 

 derstood in a general sense, and in a sort of wholesale way. 

 The exceptions, however, though at times they may be 

 rather numerous, but confirm the rule. It is, therefore, 

 practicable in most cases to harvest the crop between the 

 period that elapses from the manifestation of the first symp- 

 toms to the destruction of the tubers. 



As to the so-called new disease, it is in no symptoms 

 and results at least as old as my recollections extend. If 

 as Mr. Smith contends, it is our old foe in a new state, then 

 is the Potato disease a much older malady than has generally 

 been assumed. And I believe it is. No doubt it has be- 

 come more general, and now and then it is developed into 

 abnormal destructiveness ; but facts and observations, could 

 they be carefully collected, would probably confirm the 

 natural inference that science could now draw from its know- 

 ledge of the pest that the Peronospora, in some form of 

 its manifold life, has clung to the Potato from or before its 

 introduction into Europe. One or two points, however, do 

 not seem to be made quite clear by Mr. Smith- If the 

 destruction of the top is caused by this same pest in the new 

 disease, why is the mode of destruction so different, and how 

 is it that it stops short of the tuber? In the many cases of 

 new disease that I have examined in cottagers' gardens over 

 a wide area during the last week, not a single diseased 

 tuber was found. The stem, roots, and in most cases the 



