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weak lime-water. In the second lot the process was reversed, that is 

 to say, the potatoes were first placed in the lime-water, and then in 

 the acid. The third lot was left untouched. Ten days afterwards I 

 examined the potatoes, and found, as I expected, that the potatoes 

 which had not been treated with the sulphate were rapidly decaying, 

 — those which had been first placed in the solution of lime and then 

 in the acid were more nearly decomposed, — while those which had 

 been treated in the mode first described remained as sound as when 

 first taken in hand. Upon being cut open the diseased part of the 

 potatoes was not found to have spread internally, and the flavour of 

 the root was in no degree affected by the application of the process, 

 nor do I think that its germinating power was injured by the effect of 

 the sulphate. The effect upon the beet-roots was similar to that pro- 

 duced upon the potatoes, and which would seem to be somewhat ana- 

 logous to that of galvanizing metals, viz., protecting the substances 

 from the effect of atmospheric agencies. 1 may add, that muriatic 

 and other acids have been employed by me on other occasions with 

 equal success, the only agents required appearing to be those which 

 will most readily produce a sulphate in contact with the substances 

 required to be preserved. As at present it does not appear that any 

 means can be successfully adopted to prevent the potato from becom- 

 ing diseased while in the ground and arriving at maturity, it would 

 certainly be of immense advantage if anything could be discovered 

 by the use of which the roots when taken up could be prevented from 

 that absolute decay and irreparable loss to which potatoes affected by 

 the disease are liable. The results which I have described seem to 

 me to point to the possibility of arresting this loss. How far the plan 

 suggested may be practicable or applicable upon a large scale, my 

 present very pressing and numerous engagements have hitherto pre- 

 vented me from ascertaining. I do not think that any insuperable 

 difficulty exists with respect to the application of the process. The 

 acid employed by me was very weak, about one part to two hundred 

 of water ; the lime-water was about the consistency of milk. The 

 materials are not, therefore, expensive ; and when the value of the 

 crop to be saved is taken into consideration, it would be a matter well 

 worthy of being tested by some of those extensive growers of potatoes 

 in the county in which the British Association is now holding its sit- 

 tings. For my own part, I should be most happy if by any suggestion 

 of mine 1 had merely been the instrument of directing the attention of 

 scientific men to the subject of the possibility of preserving from total 

 destruction a vegetable so valuable and so indispensable as the j)otato." 



