82 BOTANICAL GAZETTE [FEBRUARY 
potassium or both. This view is presented by Grirritus (25), 
VooRHEES (72), and HopKINs (32). BROWNE (13) and BRUCKNER 
(14) consider the beneficial effect of gypsum due, in part at least, 
to the nutrient effect of the sulphur; while VENDELMANS (70) and 
HitGarD (31) mention its beneficial effects, particularly on the 
legumes, without giving any explanation. 
In most fertilizer experiments sulphur has Hides added, together 
with phosphorus, in acid phosphate or basic slag, or with the 
potassium in potassium sulphate or kainit. When beneficial results 
have been obtained, the investigators have invariably ignored the 
possible effects of the sulphur. This may lead to erroneous con- 
clusions, as was pointed out by Liesic (37) in 1855. He said 
that the sulphur or the calcium in the acid phosphate, or both, 
might have had a beneficial effect on the turnips in the Rothamsted 
experiments, as well as the phosphorus. 
Hopkins, Mosier, Pettit, and READHIMER (33) found that 
kainit increased the yields of corn, wheat, and oats on the waste 
hill land of Johnson County, Illinois, when used with bonemeal, 
ground limestone, and crop residues, over similarly treated plots 
without kainit. On the plots receiving no kainit, as well as on 
those receiving the kainit, cowpeas were grown once every three 
years and turned under as part of the crop residues. STEWART 
(66) compared potassium chloride and potassium sulphate as 
fertilizers for apple orchards in Pennsylvania. He found no 
appreciable difference in the effect of these salts. SmrrH (65) 
found a greater yield of oat straw for potassium sulphate than 
potassium chloride in pots containing Hagerstown silt loam. 
Brooks (8) compared the effects of potassium sulphate and 
potassium chloride on alfalfa in field experiments at the Massachu- 
setts Agricultural Experiment Station. Both plots received 600 
pounds of bonemeal per annum, and both received 2 tons per 
acre of hydrated lime before planting the alfalfa. Both Grimm 
alfalfa and common alfalfa were used. Potassium sulphate gave 
increased yields of 0.50 tons of Grimm alfalfa and 0.75 tons of com- 
mon alfalfa over potassium chloride. In every case the alfalfa on the 
plots receiving potassium sulphate was a darker green than on the 
plots receiving potassium chloride. The same difference in color 
