106 ON thj: rust on 



elude the seeds, or prevent the fungus, growing 

 on their pickles and preserves, even by tied 

 down bladders and tight corks ? And if horse- 

 dung in a mass be placed in certain situations, 

 it is well known that even the large edible mush- 

 rooms will rise and grow where they never were 

 seen before. 



Thus, then, if the cause of the rust or black 

 blight be as I have stated, — and the observations 

 both of Sir John Sinclair and Mr. Knight con- 

 finn my opinions, and the observations of Sir 

 Joseph Banks do not controvert them, — the 

 remedy is simple and obvious : viz. for the pro- 

 duction of seed crops ; let manuring follow, and 

 not immediately precede them; or at any rate^ 

 dung should not be ploughed in, on such lands, 

 immediately before sowing the seeds. 



And it is equally obvious, that the ploughing 

 in, green crops, must be conducive to the produc- 

 tion of rust. And the feeding off turnips with 

 sheep, or folding them on the land, immediately 

 before sowing, must have a strong tendency to 

 the same effect. 



li'f when lands are manured, two oi' three 

 succulent or green crops be taken off, before it is 

 sown for seed-crops, although the leaf and plant,, 

 or straw or haulm, of such crops may not appear 

 so luxuriant in consequence, the seed will be 



