Experiments upon Swedes. 1 79 



was uniform in its character, and also that gypsum had no effect 

 whatever on the turnip-crop. 



Plot XII. — Manured with 3 cwt. of home-made superphos- 

 phate : — 



Produce .. 10 tons 12 cwt. 21 lbs. 

 Increase .. 4 tons 1 cwt. 25 lbs. 



The superphosphate used in this experiment was made on our 

 farm from coprolites, fine bone-dust, sulphuric acid, and salt. 

 It yielded on analysis — • 



Water 22-83 



* Organic matter 4'88 



Bi-phosphate of lime 8-28 



Equal to bone-earth, rendered sohil)lc by acid .. (12"91 ) 



Insoluble phosphates 16'21 



Hydrated sulphate of lime 37'42 



Alkaline salts (common salt) 5'53 



Insoluble silicious matter (sand) 4'85 



100-00 



* Containing nitrocren '55 



Equal to ammonia "66 



It will be observed, that this superphosphate contains little 

 ammonia, and about 5|^ per cent, of salt besides soluble and 

 insoluble phosphate. In its effect upon the crop it was nearly 

 equal to the superphosphate used in Plot VII., which is a far 

 superior and more expensive fertilizer. 



Again, it will be observed, that it produced a better result than 

 the superphosphate made by dissolving fine dust in sulphuric 

 acid, and costing at least ?>0s. more per ton. 



Plot XIII. — ^kianured with Ig cut. of sulphate of ammonia : — 



Produce .. 5 tons 6 cwt. 21 lbs. 

 Decrease . . 1 ton 5 cwt. 2 qrs. 3 lbs. 



The sulphate of ammonia used in this experiment was found to 

 consist in 100 parts of: — 



Pure sulphate of ammonia .. 98-28 



Fixed salts -78 



Moisture -94 



100-00 



The roots on this plot came up much later, and throughout 

 the whole experimental period were in a backward condition, 

 when compared with the rest of the field. 



The plants looked decidedly worse than those on the unmanured 

 portion. I mention, especially, that the swedes, contrary to 

 what I expected, had a less luxuriant foliage than even on the 

 unmanured plot. 



X 2 



