DR. DAUBENY ON THE ROTATION OF CROPS, ETC. 

 The following diagram will show the variations in the yearly produce 



Hemp. 



195 



>lbs. 



In the contiguous bed recently manured the crop weighed 45*4 lbs., somewhat 

 more than the average of the shifting, and considerably exceeding that of the perma- 

 nent beds. 



5. Linum usitatissimum. 



Flax presents a gradual, though not an uniform, rate of deterioration, the shifting 

 crop always standing in advance of the permanent one. 



In this instance I tried the same experiment as in the case of the potatoes, namely, 

 that of sowing one bed with seed from the last year's crop, and the second with seed 

 obtained from some other source. The latter produced much the most abundant 

 crop, but I am now inclined to attribute its superiority chiefly to its succeeding a 

 crop of Valerian, a plant which probably draws little from the soil, and which conse- 

 quently having grown in it for five successive years, had given time to the materials 

 of the earth to undergo decomposition, so that an accumulation of nutritious prin- 

 ciples may have taken place in it, nearly as would have been the case if it had been 

 left entirely fallow. 



MDCCCXLV. 



2d 



