464 MONTHLY JOURNAL OF AGRICULTURE. 



THE POTATO ROT. 



" Rot me," as the boy says, if— after giving what follows, from the London Gar- 

 deners' Chronicle — we trouble the reader with anything farther on this subject 

 for a twelvemonth to come — unless either Professor Norton, Mr. Teschemacher, 

 of Boston, or Professor Lindley himself, should aver that something new and of 

 practical utility, to be relied on, has come to light : 



Dr. Buckland's letter on the Potato Disease, together with those of Mr. Wilkinson and 

 Sir Gaspard le Marchaut, has revived the vexed question of how the disaster was produced. 

 It reminds us of stories current in Ireland in October and November, 1845, when it was 

 firmly believed by many persons, that the miscliief was produced by lightning. There was 

 one case in particular of a field sloping to the sea-shore, on the north-east coast, the whole 

 of which was blighted in a night, and fishermen who were lying off the coast that night de- 

 clared that the surface of the field seemed light with gleams and coruscations. 



We are far from venturing to assert that some peculiar electric condition of the atmosphere 

 has been the real cause of this scourge ; but we are equally far from denying it. We think, 

 too, that evidence of the disease being connected with some peculiar atmospheric condition 

 of a deleterious nature, acquires more and more force as time wears on, while at the same 

 time the ai'guments to the contrary' become weaker and weaker. The peculiar affection of 

 the tomato in 134G, which, as far as we saw, was confined to the side of the fniit freely ex- 

 posed to view, and consequently to direct atmospheric influence, seems to corroborate the 

 views of Dr. Buckland and Mr. Milne. 



At all events it appears certain that unless this visitation is removed by Providence, it is 

 not likely to disappear; for the skill of Man has been directed in vain, not merely to its re- 

 moval, but even to its mitigation. If it proved to be last year less destructive than in 1845 

 and 1846, the change can hardly be referred to any human cause. Time has now permitted 

 a trial of the various remedies which have from time to time been proposed in different coun- 

 tries, and the result is that all, without a single exception, have failed. 



The most complete series of experiments hitherto made public is that tried last year in the 

 Garden of the Horticultural Society, and reported upon in the Society's " Journal," just pub- 

 hshed. In the absence of a clue to the first cause of the disease, experiments are necessarily 

 empirical ; and therefore every kind of remedy, probable or improbable, which had been 

 heard of, was put to the test, from charcoal up to soap jelly. The results must, we imagine, 

 show the hopelessness of dealing with an enemy so capricious in its attacks that a result ob- 

 tained in one place is directly reversed in another place only a yard or two oft' — there being 

 no appreciable difference in soil or situation or circumstance. For example, the per centage 

 of diseased potatoes found where nothing had been used in the soil was as high as 32'50 and 

 as low as 5-74. And although in the cases of some applications no disease whatever was 

 found when the crop was taken up — nevertheless in many instances the very same applica- 

 tioas were found connected with above 50 per cent, of disease. The following Tables, 

 abridged from Mr. Thompson's Report, will make this still clearer : 



Rate per cent. 

 Substances employed. diseased. 



1. Lime and chai-coal 13-24 



2. Do. do 20-66 



3. Do. do 18-24 



Average of the above three rows 17-38 



4. Nothing 20-88 



5. Do 29-40 



6. Do 21-92 



Average of the above three rows 24-06 



7. Sah, hme and charcoal 31-05 



8. Do. do. 22-81 



9. Do. do. 13-77 



Average of the above three rows 22-54 



10. Nothing 23-00 



11. Ash-leavedkidney,youngtubers grown 



12. in 1837 planted 2400 



13. Nothing 8-50 



14. Watered with weak chloride of lime .17-52 



15. Do. do 19-28 



16. Nothing 32-50 



(864) 



Rate per cent. 

 Substances employed. diseased. 



17. Salt, potash, and fat 12-17 



18. Sulphuric acid, diluted (half row) 5-19 



19. Powdered charcoal (half row) 7-73 



20. Salt 3-86 



21. Coal-tar sprinkled over the sets 3-70 



22. Nothing 6.65 



23. Chalk, salt and charcoal 4-45 



24. Do. do. 6-89 



Average of the above two rows 5-67 



25. Sulphate of soda and nitrate of soda ..14-64 



26. Salt successively applied 6-44 



27. Do. do. 7-50 



Average of the above two rows . . 6-97 



28. Sulphur 6-03 



29. Salt and sulphate of magnesia 938 



30. Do. do. 7-36 



Average of the above two rows 8'37 



31. Moberly'B sulphate of magnesia 12-26 



32. Sets dipped in lime 7-70. 



