582 Summary of Agricultural Experiments, [oct., 



of such manures under a considerable variety of conditions. The 

 improvement in the pasture was measured by the increase in weight of 

 stock (mainly sheep) fed upon five plots at each of six centres. At 

 five centres the plots were each four acres in extent, while at the 

 remaining centre they were only three acres. The grazing seasons 

 for the sheep varied slightly, commencing in May and ending in 

 October. At each of the centres one plot was left untreated, while 

 three of the others were supplied respectively with 200 lb. phosphoric 

 acid per acre in the form of 10 cwt. of basic slag; 10 cwt. of basic 

 slag and 100 lb. of potash per acre in the form of 210 lb. of sulphate 

 of potash ; and 200 lb. phosphoric acid per acre in the form of 9 cwt. 

 of superphosphate, and, in addition, 10 cwt. of ground lime per acre. 

 The remaining plot was supplied with nitrogen by feeding the sheep 

 with a mixture of equal parts of decorticated and undecorticated cotton 

 cake, the cake used supplying about 50 lb. of nitrogen and 20 lb. of 

 phosphoric acid and potash per 1,000 lb. 



The soils on which the experiments were conducted were nearly 

 all of low quality, but were not deficient in nitrogen, potash, or 

 phosphate, and seemed to require physical improvement rather than 

 manuring. The manuring with cotton cake and phosphate, there- 

 fore, was not very profitable. Throughout these experiments an im- 

 provement was effected by all the manures, but only in the case of 

 basic slag was the improvement such as to make the application of 

 manure remunerative, ' the increase in weight of the sheep being valued 

 at 3<i. per lb. Even in the case of basic slag no great and rapid 

 improvement was effected such as took place during the well-known 

 experiments at Cockle Park, and on the average three or four years 

 had to elapse before sufficient return was obtained to pay for the 

 slag. On the other hand, the effect of the slag was not exhausted 

 after six years, the returns from the manure at the end of that time 

 being nearly as large as ever. Potash, in the form of sulphate o f 

 potash, applied along with basic slag, though it gave a small increase 

 in most of the experiments, did not give sufficient return to pay for 

 its cost. Superphosphate and lime, though in all cases giving a con- 

 siderable increase in mutton, did not in general give sufficient return 

 to be remunerative, and in no case gave so good a return 

 as the cheaper dressing of slag alone. In some of the experiments 

 the soil was covered with a very thick, coarse sod of grass of poor 

 quality. On such land clover plants have not room to develop, and 

 the effect of the manure was only shown very slowly. Sheep alone 

 are unable to eat down the grass sufficiently, and better results are 

 obtained when both sheep and cattle are grazed on the same plots. 

 At one centre, where the pasture was of better quality than at the 

 others, and where there was a considerable proportion of good grasses, 

 no satisfactory result was obtained from any treatment, and the con- 

 clusion drawn is that land of such quality requires to be improved 

 by quite different methods. 



It was noticeable at each centre that a much greater increase in 

 the weight of the sheep was made during the early part of the summer 

 than during the later months. Roughly speaking, the increase in the 

 first eight weeks of the grazing season was twice as great as in the 

 remaining twelve weeks. The influence of the weather was also 



