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pctash was so used, while, on the contrary. Director Giessmann, of 

 Massachusetts, when making experiments to compare the effects of 

 the two says that the yield of potatoes was in every instance larger 

 where sulphate of potash had furnished the potash of the fertiliser ;_ 

 and Director Scovell, of Kentucky, appears to be of the same opinion. 

 He adds that the potatoes contain the largest amount of dry matter, 

 and are, therefore, of the* best quality. Mr. W. P. Brooks, of Amherst 

 Station made eight experiments comparing muriate and sulphate 

 of potash, when the latter gave an average of 22.1 bushels more 

 of merchantable tubers, and the eating quality has generally been 

 better, as containing less water and more starch. Mr. T. M. White, 

 of New Brunswick, New Jersey, says that, averaging three experi- 

 ments, muriate and sulphate yield practically the same; but that- 

 potatoes grown with the latter are best when cooked, while muriate 

 is somewhat cheaper. The New Jersey Experimental Station, in 

 U.S. harvested on three farms also more tubers from muriate of 

 potash, but from sulphate of potash they contained slightly more 

 starch, viz., 16 Ib. per acre. Mr. Whittemore, of Colebrook, New Hamp- 

 shire, says for that State! the composition of manures should be 9 to 11 

 per cent, of phosphoric acid, 9 to 15 per cent, of potash, and 2 to 4 

 per cent of nitrogen. Phosphoric acid used alone at Storr's Station, 

 Connecticut, or in combination with nitrogen, brought but little 

 over nothing. Professor Wagner records the same result of a 

 sandy soil, and Director Scovell, of Kentucky, said that 200 Ib. of 

 sulphate of potash produced slightly more than 80 loads of stable 

 manure, and results showed decidedly that there was a profit in the 

 use of potash compounds. The money expended in sulphate of 

 ammonia and superphosphate was entirely lost. Mr. D. D. Johnson, 

 of West Virginia, obtained from 800 Ib. of kainit with phosphoric 

 acid (as 2 to 1) 161-J bushels per ,acre, or a net profit of 11/9/6 

 per acre, less the cost of digging the increased crop. The 

 careful experiments at the New York Experiment Station con- 

 cerning the relative effect of muriate and sulphate of potasli upon 

 the composition of the potash were inconclusive. 



Professor Dr. Maercker made experiments in largei vessels 

 filled with a light sandy soil, to which 2J per cent, of peat was 

 added for the purpose of ascertaining the results with different 

 potash salts. Each vessel received 2 g. of nitrogen in form of 

 sulphate of ammonia, 1 g. of soluble phosphoric acid, and 20 g. of 

 carbonate of lime. One-half of the vessels received also at he 

 rate of 97 Ib. of potash per acre, the other at the rate of 193 Ib. 

 The variety "Professor Maercker" potatt^s were planted on the 10th 

 day of April, 1896, and harvested in the drst days of October. Those 

 with less potash gave, where kainit WHS used, 141 g. ; with sul- 

 phate of potash, 159 g. ; and muriate of potash, 234 g. of tubers. 

 The double quantity of kainit gave 195 g., of sulphate of potash 

 298 g., and of muriate of potash 337 g. The starch was with fhe 

 smaller doses of potash almost equal : with the larger, muriate of 

 potash had a percentage of 16.67, and sulphate of potash of 17.30,, 

 but the larger crop of muriate gave 23 g. more of starch. 



