Experiments upon Swedes. 

 Experiments upon Swedes made at Craigie House^ Ayr. 



19 



Plot. 



9 

 10 

 11 

 12 

 13 

 14 



15 



Manures applied per Imperial Acre. 



Cost 



of Manure 

 per Acre. 



No manure 



1^ cwt. of sulphate of ammonia 

 3 cwts. of sulphate of ammonia 



2 cwts. of sulphate of ammonia and 3 cwts. j 

 of superphosphate, made from bone-ash >! 

 and sulphuric acid (dissolved bone-ash) ) ! 



5 cwts. of dissolved bone-ash, the same as 

 that used in No. 4 



5 cwts of dissolved bone-dust 



7 cwts. of dissolved bone-ash, the same as 



in No. 4 



3 cwts. of dissolved bone-ash, the 

 sample used in No. 4 



10 cwts. of dissolved bone-ash 



6 cwts. of phospho- Peruvian guano . . 



No manure 



6 cwts. of Peruvian guano 



1 1 cwts. of dissolved bone-dust j 



30 tons of Dublin street-manure, including') j 



cartage / 



5 cwts. of Ritchie's dissolved bones .. 

 10 cwts. of Ritchie's dissolved bones 



1 4 



2 8 



320 



1 15 



1 17 



2 9 



1 1 



3 10 

 3 12 



3 18 



4 2 



300 



1 17 

 3 15 



Produce 



per Imperial 



Acre. 



tons. cwt. qrs. Ibs. 



17 







18 17 

 20 17 







16 

 2 



1 12 



26 15 1 12 

 24 17 - 14 

 24 19 1 4 



24 







24 10 

 30 6 



2 24 

 1 2 



16 

 31 10 20 

 30 8 2 8 



2 8 



1 20 



2 8 



A careful reader will not fail to notice some strange discre- 

 pancies in the preceding experimental results. Thus it will 

 strike him as peculiar that 3 cwts. of dissolved bone-ash yielded 

 24 tons of roots, whilst 7 cwts. of the same manure gave only 

 about 1 ton more, and 10 cwts. only 10^ cwts. more per acre. 

 5 cwts of dissolved bone-ash, on the other hand, gave 26 tons 

 15 cwts. 1 qr. 12 Ibs. 5 cwts. thus appear to have produced a 

 heavier crop than 10 cwts. of the same manure. 



I do not pretend to explain these discrepancies, but have no 

 doubt the experiments were carefully made, and can only say 

 that, for some reason or the other which often escapes our notice, 

 some strangely anomalous results are sometimes obtained in 

 field-experiments. The chief practical lessons which may be 

 derived from these experiments appear to me to be 



1. That sulphate of ammonia had little effect upon turnips, 

 even when applied to a light, sandy loam. 



2. That the addition of sulphate of ammonia to superphos- 

 phate seemed to have had no decidedly beneficial effect on the 

 crop. 



3. That 5 cwts. of good superphosphate appear to be a surfi- 



C 



