FERTILIZERS. 735 



of the main causes of the variations in the action of the nitrog-en. 

 When the conditions in the preparation of the manure ai-e such as to 

 result in the removal of a large part of the nitrogen-free organic 

 matter, the transformation of the nitrogen into forms which are readily 

 assimilable by plants is almost entirely prevented. Neither ammonia 

 nor elementary nitrogen is formed, and even amids are formed from 

 proteid nitrogen to a very limited extent. An important after-effect 

 of the nitrogen of manure was noted. A part of the nitrate nitrogen, 

 in case of applications of manure, is fixed, and may result in a direct 

 increase in the utilization of nitrogen or may exert an after-effect in 

 increasing the yield of the succeeding crop. The theory of Gerlach 

 that there are certain kinds of manure which produce more nitrates 

 than they destroy, and thus do not cause a loss of the nitrogen of 

 nitrates used in connection with the manure, is not su])stantiated 

 by the authors' experiments. 



The fifth year's observations upon the effectiveness of nitrate 

 of potash, as compared -with like amounts of nitrogen and potash 

 in form of muriate of potash and nitrate of soda, H. J. Wheeler 

 and J. A. Tillinghast {Rhode Idand Sta. Iij>t. 1899, 2>P- 17Jf-176). — 

 The experiments of previous A'ears (E. S. R., 11, p. 91-1) on this subject 

 were continued during 1899. The results obtained are briefly sum- 

 marized in this article. 



"The data for the 5 years since this experiment was l:)egun show as yet no striking 

 differences between the results with nitrate of potash and those secured with Hke 

 quantities of nitrogen and potash as nitrate of soda and muriate of potash. It is evi- 

 dent, therefore, that with the amounts of nitrogen and potash employed neither the 

 chlorin nor the soda has as yet proved of positive advantage either as a direct or 

 indirect manure. Incidentally, the experiment has shown the inferiority of gypsum 

 (land plaster) as a source of lime for a sour soil, as compared with air-slaked lime." 



Observations upon the growth of plants on an acid upland soil, 

 limed and unlimed, H. J. AVheeler and J. iV. Tillingiiast {Rhode 

 LJand Sta. Bid. 69, jjj). 177-204; fiy^- 7). — This is an account of a 

 continuation during 1899 of observations which were begun in 1893 

 (E. S. R., 11, p. 915). During this period nearly 200 different kinds 

 of plants have been tested. Ko lime has been applied since 1894. 

 The kinds and amounts of other fertilizers used in 1899 were the same 

 as in the previous year. Data for grow^th and 3'ield of crops on the 

 different plats are reported in detail. The principal restilts may be 

 summarized as follows: 



Plants benefited hy J fining. — Orange quince, black Tartarian cherry, 

 early Richmond cherry, Burbank Japan plum, American linden, Amer- 

 ican elm, rhubarb, Australian saltbush, hemp, asparagus, red rasp- 

 berry (Cuthbert), red and white currants, barle}', oats, spring wheat, 

 mangel-wurzels, chicorv, onions, English turnips, sweet peas, balsams, 

 and poppy. 



