288 EXPEPJMKXTS ON POTATOES WITH DIFFEEEXT MAXUEES. 



In column 2, Table II., the unaided phosphates are brought into 

 prominence. In column 3 the same phosphates, plus sulphate of 

 ammonia, are brought into prominence, and averaged. If we 

 compare the two, it is seen that the sulphate of ammonia has 

 increased the average crops by 1 ton 6 cwts. The addition of 

 kainit (see column 4) has lessened the crop by 10. cwts. per acre, 

 and the potashes (see column 5) has lessened it by 5 cwts. 



Table III. SJioivs the Value of the Crop per acre at £3 per Ton, 

 the Cost of each Mcmurial Apijliccttion, the 'vcdue of the Crop 

 after deducting this and the Profit produced over and above 

 the Value of Crop vnth no Manure. 



It is to be noticed that the three so-styled "unaided phosphates" 

 have produced nearly equal crops ; but, owing probably to the slower 

 assimilation of the undecomposed nitrogen in the bone super- 

 phosphates than of the 35 lbs. sulphate of ammonia added to the 

 coprolite superphosphates — to equalise the nitrogen — the former 

 produces rather the smaller crop. Wlien, however, 2 cwts. of 

 sulphate of ammonia are added to each, the bone superphosphates 



