ON THE CONTINUED CULTIVATION OF WHEAT. 



19 



ment has now been continued five years, and one or two interest- 

 ing facts have been observed during its progress ; though it was 

 rather to be regretted that the soil in which the wheat was grown 

 was too well manured previous to the commencement of the 

 experiment. It is hardly necessary to observe that the whole 

 experiment was intended as one purely horticultural, or rather 

 even, chemical ; and that the results obtained cannot be con- 

 sidered as giving at all accurate information as to the agricul- 

 tural value of the salts employed as manure. 



The general results of the experiment will be seen in the 

 following Table, which shows the whole weight of crop obtained 

 each year per rood : — 



Manure Used. 



1. Phosphate of Ammonia, 3 lbs. 



2. Sulphate of Soda, 3 lbs. . . 



3. Common Salt, 3 lbs. . , 



4. Muriate of Ammonia, 3 lbs. 



5. Phosphate of Lime, -lilbs. . 



6. Muriate of Potash, 3 lbs. 



7. No Manure 



8. Sulphate of Lime, 4i lbs. 



9. Sulphate of Ammonia, :i lbs. 



10. Sulphate of Magnesia, 3 lbs. 



1 1. Sulphate of Potash, 3 lbs. . 



12. Nitrate of Soda, 3 lbs. . . 



1843. 1844. 



lbs. oz. 

 49 

 33 13 

 46 11 



53 1 

 46 



51 9 

 35 7 



54 3 



52 3 



49 11 

 44 10 



50 12 



lbs. oz. 



34 10 



35 2 

 37 15 

 37 9 

 37 15 



35 



36 4 

 43 8 



1845. 



1846. 



lbs. oz. 

 30 11 

 30 3 

 40 11 

 39 12 

 28 11 



38 1 

 37 



30 11 

 36 4 



31 



39 10 

 26 8 



lbs. oz. 



41 1 

 36 10 

 32 8 

 46 12 

 32 13 

 30 



42 14 

 41 9 

 46 2 

 SI 12 

 39 8 

 41 



1847. 



lbs. oz. 



45 4 



43 



37 4 



46 

 25 3 

 35 14 



38 3 

 60 



44 4 

 37 8 



39 11 

 41 



It appears from this table that in the first year the production 

 of vegetable matter was increased by all the salts employed, 

 excepting only the sulphate of soda. This effect fell off more 

 and more in each succeeding year, for in 1844 sulphate and 

 nitrate of soda, muriate of potash, and phosphate of ammonia 

 gave less crops than the ground with no manure; in 1845 we 

 find sulphate and nitrate of soda, sulphate of magnesia, sulphate 

 of potash, sulphate and phosphate of ammonia, and sulphate of 

 lime apparently doing harm; and in 1846 the ground with no 

 manure gave a better crop than any of the others, excepting 

 those manured with muriate and sulphate of ammonia. The 

 fifth year, however, more nearly resembles the second, for in it 

 seven of the salts appeared to do good, viz., phosphate, sulphate, 

 and muriate of ammonia, sulphate of soda, lime and potash, and 

 nitrate of soda. 



On comparing together the total produce of each manure, 

 during the whole five years, it will be found that the entire 

 quantity of vegetable matter had been increased in every case, 

 excepting where phosphate of lime and sulphate of soda were 

 employed as manure. 



In the preceding Table the entire quantity of straw and grain 



c 2 



