FERTILIZERS. 461 



It was found "that the yearly inaxiina and minima are reached at practically the 

 same time for the air and the iipjter few inclieH of soil, and that the annual wave of 

 temperature progresses somewhat regularly downward, although of course somewhat 

 distributed by temporary changes in the weather, requiring about a month to reach 

 tlie dejith (jf our lowest thermometer." 



The movement of the frost line and periodic changes in temperature are briefly 

 discussed. 



Uses of peat and its occurrence in New York, H. Ries {Aibamj: Univ. State of 

 Xeir York, pp. 36, iUus.). 



The study of soils and agronomic charts, H. Lagatu {L'ltude dcs terres et les 

 cartes agronoiniqncs. Mo)ttpeUer: Coulet tt Son, 1903, pp. 31). — This article discusses 

 the preparation and use of soil maps or agronomic charts and reports studies of the 

 (juarternary diluvium of Vendres and the blue tertiary marls of the Montady basin 

 with suggestions as to the fertilizer requirements anil management of these soils. 



The frontier of physiography, W. H. Hobbs {Science, n. ner., 18 {1903), No. 460, 

 pp. 538-540). — This article explains the province and importance of a study of 

 epeirogenic phijvoyrapliy, as distinguished frcnn orogenic ijhgsiographii, in its relation 

 to the architecture of the earth's surface, and refers to investigations made in south- 

 western New England which indicate "that for a large area the earth's physiognomy 

 is the outward expression of its internal structure." The results of this study in 

 detail are to appear in a monograph of the U. S. Geological Survey. 



FERTILIZERS. 



Experiments upon the use of potash as a fertilizer, H. J. Patterson {Mary- 

 land Sta. Bid. 89, pp. 165-196). — This bulletin gives a brief historical account of the 

 use of potash in agriculture; discusses the role of potash in plants, the quantity 

 removed from soils by plants, origin and condition of potash in soils, sources and 

 forms of potash fertilizers; and reports experiments begun in 1897 on tenth-acre plats, 

 of medium, stiff, clay loam having fairly good drainage, for the purpo.se of studying 

 "some of the underlying principles surrounding the use of potash fertilizers as to 

 their time and method of ai)i)lication, their relation to other plant foods and ingre- 

 dients which enter into the different sources of supply, and to make a general study 

 of the effect of potash on the quality of the crop. ' ' 



Kainit, muriate of potash, sulphate of potash, sulphate of potash and magnesia 

 (double manure salt) were applied (1) just before planting, (2) for spring crops in 

 the fall and fall crops in the spring. Other potash fertilizers used in the series of 

 tests were carbonate of potash and magnesia, wood ashes, cotton-hull ashes, and 

 silicate of potash. Lime at the rate of 800 lbs. per acre with muriate and sulphate 

 of potash, and muriate of potash, with and without lime, combined with sufficient 

 dissolved rock phosphate to furnish phosj)hqric acid equal to that in wood ashes 

 were also tested in the series. One plat received barnyard manure at the rate of 5 

 tons per acre and a number of check plats received no potash. 



The fertilizers were applied broadcast just before planting or 3 to 6 months before. 

 The results obtained with 6 crops — corn, late potatoes, cowpeas, wheat, hay, and 

 early potatoes — are reported and "with one exception, all favor applying fertilizers 

 which contain much chlorids, several months before planting the cro}), and those 

 having the ijotash as sulphate at the time of planting the crop. The croj) of cowpeas 

 gave results just the reverse. It is a matter of interest to note that the results obtained 

 give about the same figures favoring applying chlorids a considerable time before 

 planting crop, as was obtained favoring the application of sulphates at time of plant- 

 ing the crop; that is, by excluding the cowpea figures, there was in 5 crops 

 3,527 lbs. more product obtained by applying chlorin potash salts 3 to 6 months 



15293— ]^o. 5—04 4 



