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the Board of Agriculture ; and the third by Mr. W. C. Little, in 

 1883, undertaken for the Royal Agricultural Society of England.* 

 These inquiries were conducted pretty much upon the same 

 lines, by means of a Schedule of questions forwarded to leading 

 agriculturists in different parts of the country ; and although in 

 the first two the results are not particularly conclusive, except, 

 perhaps, as to cold, changeable weather being, to a great extent, 

 the cause of mildew, there are more definite conclusions 

 stated by Mr. Little, which may be given here in his own 

 clear words : 



1 . "It would appear that seasons are the chief cause of 

 mildew, and that sudden changes of temperature and rain, 

 accompanied by close, still weather, are favourable to the 

 spread of the disease. 



2. That low-lying soils are most subject to this attack. 



3. That high farming and too generous manuring, parti- 

 cularly with nitrogenous manure, promote mildew. 



4. That early sowing is desirable on all land subject to 

 mildew. 



5. That a thin and gathering crop runs more risk of the 

 disease than an evenly-planted -crop." 



Mr. Little also received most important communications 

 from Sir J. Lawes and Dr. Augustus Voelcker, which are worthy 

 of reproduction here, as they show that the effects of mildew 

 depend materially upon the constituents of the soil. Thus, Sir 

 John Lawes writes : " I consider that plants are liable to be 

 attacked by fungi, parasites, insects, &c., in proportion as the 

 soil is deficient in available mineral food. I happened to pass 

 through the Fen district in the summer of 1881, and I 

 particularly noticed the dreadful state of the wheat in that 

 district ; and as my own wheat, although not a good crop, had 

 not suffered from mildew, I was anxious to know whether the 

 season in that district possessed any special characters differing 

 from my own. According to my view, fen-land wheat should 

 be especially liable to mildew, as the balance of the soil-con- 

 stituents is organic and not mineral. Ordinary arable land 

 such as mine contains about 97 per cent, of mineral matter, 

 and 3 per cent, of vegetable substances. Some of the fen land 

 must have these proportions almost reversed. It is quite pos- 

 sible that when the climate favours mildew, it will prevail more 

 or less, but the extent to w*hich it will prevail, will greatly 

 depend upon the relation between the mineral and organic 

 matter in the soil, and I should be disposed to say that the 

 greater the amount of available mineral matter, potash, lime, 

 silica, phosphate at the disposal of the plant, the greater 

 would be its power of resistance." f 



* The Journal of the Royal Agricultural Society of England, vol. xix., 

 2nd ser. 



j- Mr. Little's Report, Journal of the Royal Agricultural Society, vol. 

 xix., 2nd aer. 



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