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EXPERIMENTAL STATION'S — UEPORT FOR 1879. 301 



ahead ol' the others. Fish [i,uano labours iiiider the same dis- 

 'advantaii;e as pots 5, 15, and IG; it contains a considerable 

 amount of i'atty matter which resists decomposition in tin; soil, 

 and retards the action of the manure. 



Of the snperphos])hatcs, that containing 10 per cent, soluble 

 phos]iliatc has done best, and the further increase of dissolved 

 phosphates has still further reduced the crop. 



The great advantage of heavy manuring to a poor soil is seen 

 in pots (h) of the next four nundjers. 



Tot M5 received nothing but sulphuric acid, \\liicli was well 

 incorporatetl with the upper half of the soil, and the amount 

 given was the same as that used for dissolving the phosphates in 

 plot 30. The result is seen to be a failure. Pot 36 is un- 

 manured soil in which light seed was sown. The miseraljle 

 result obtained shows the importance of selecting for seed only 

 the heaviest grain. Pot 37 is an odd one which contained rich 

 garden soil, and which was set down as a base for comparing the 

 fertility of the other pots ; only the heaviest nianurcd pots liave 

 been able to compete with it. 



Pot 27, which received no manure, has produced a crop better 

 tlian some of those which received partial manures. This is an 

 experience not unfroquently met with, and in this case I suppose 

 it must be the result of some superiority in the soil. The means 

 adopted for mixing the soil may not have been thorough enough, 

 iind more care will in future experiments be paid to that matter. 



An attempt was made to estimate the amount of root growth 

 made in the various pots, but it was not found possible to separ- 

 iite the fine rootlets from the earth without considerable loss. 

 So far as could be noticed, however, the amount of roots was in 

 general proportionate to the luxuriance of growth of the straw. 



The results of this carefully carried out series of experiments 

 has been to corroborate, in most particulars, those obtained with 

 the same' manures at Pumpherston station. 



For the success of this series of experiments I am much in- 

 debted to Mr Thomas Whyte, Liberton, who watched and tended 

 the pots with the utmost care. 



