Soluble Constituents In Alluvial Soil. 41 



manure, probably becaaise of its solvent chemical action on the 

 mineral constituents of the soil. The superphosphate, slaked 

 lime, nitrate of soda and blood manure seemed to be ecjuivalent 

 as regards the sandy soil, but the two former were more effi- 

 cient in the clay soil. The star phosphate and bone-dust exer- 

 cised iii stronjjf action on the clay soil, but none on the sandy 

 soil, while the g;ypsum reduced the yield on both. The order of 

 value for the manures, in the proportions given, are as follows: — 

 For the sandy soil — (1) Quicklime ; (2) superphosphate, slaked 

 lime, nitrate of soda, blood manure ; (3) ammonium sulphate ; 

 (4) star phospha/te, bone dust, and no manure; (5) gypsum; 

 For the clay soil — (1) Slaked lime, star prosphaite ; (2) bone 

 dust, nitrate of soda, superphosphate ; (3) blood manure, sul- 

 phate of ammonia; (4) unmanured and gypsum : (5) quicklime. 



In such cases as these no analyses of the soil, of the crop, 

 or of the manure would enable the results of the application 

 of the latter to be predicted, hence it is essential that the 

 farmer should be guided by local tests rather than by general 

 principles, which are often misleading if improperly applied. 

 Herein lies one of the chief justifications for the existence of 

 experimental plots on farming land throughout the State. a.iid 

 one of the reasons for the avoidance of too much centralisation 

 of experimental field-work in one locality. 



A point of great interest is to compare the above data with 

 the fluctuations in the soluble water, and of the humus in the 

 soil. The soil saimples were taken from the surface and from 

 depths of 8 and 16 inches, weighed, dried, weighed again, and 

 soaked in 2 litres of distilled water per kilogram of soil. In 

 the first experiments, the clear filtered liquid was boiled down 

 to a small bulk at Burnley, and sent to the University for final 

 testing. Tiie escape of the dissolved carbon dioxide, and the 

 concentration caused, however, a considerable loss, so that all 

 the soil samples were sent to the University, there extracted 

 and fliteied. One-half of the liquid added to the soil was 

 evaporated in the same vessel in which the residues were 

 weighed. The total number of soil samples exceeded 400, and 

 the weight nearly hall a ton. 



Some idea as to the prevailing conditions in regard to mois- 

 ture and temperature is presented by the following data, giving 

 the percentage of water and the temperatures at dift'erenr depths 



