88 Field Experiments of Crude German Potash-Salts 



powers of the field without manure, in order to form a correct 

 estimate of the value of the manures experimented on. 



The soil of the experimental field was a rather dark-coloured 

 sand, about 1 foot in depth, and resting on a raw yellow sand. 



A portion of the soil was submitted to analysis, and the 

 following results obtained : — 



Composition of Exjyeriinental Mangold Field at Talney Warren, Abingdon. 



Soil dried 

 at 212° Fabr. 



Organic matter 5*88 



Oxides of h'on and alumina 4'11 



Carbonate of lime '62 



Magnesia -22 



Potasli and soda •14 



Phosphoric acid '07 



Sulphuric acid '04 



Insoluble silicious matter (fine sand) and loss .. 88"92 



100-00 



This analysis shows that in this soil sand greatly preponderates, 

 that lime is deficient, and but very little potash and soda exist. 

 It appeared thus peculiarly well adapted for trials with potash- 

 salts. 



The land on which the mangolds were grown was uncultivated 

 until 1863, growing grasses of a rough, coarse kind, principally 

 the hassock-grass {^Aira ccespitosa). 



The surface was pared and burned early in 1863, and the 

 land drained. The greater part of the ashes were spread on 

 the land, and oats sown in March, In 1864 another crop of 

 oats was groAvn without manure. The land was then cultivated 

 in the autumn and afterwards ploughed and subsoiled. It was 

 then ridged up with farmyard dung and mangolds — long red, 

 drilled on the 27th April last Avith 3 cwts. superphosphate per 

 acre. The plants came up well ; and after they had been hoed 

 and singled, common salt and salts of potash were applied 

 separately in various quantities on the 1st July. 



On the 6th July there was a heavy fall of rain, and again 

 on the 13th another soaking rain, Avhich I considered would 

 Avash into the soil all the most soluble parts of the salts. 



The effect of the common salt was soon apparent. By the 

 first week in August the eye could clearly detect different shades 

 of colour in the leaves of the different plots, Avhich by the 

 middle of the month became still more marked. The leaves 

 of the mangolds dressed with salt had a decidedly lighter colour 

 than the rest; those dressed with potash-salts were somewhat 

 darker and less yellow in hue ; and where no top-dressing was 



