116 EXPERIMENT STATION RECORD. 



alkali. The upper lands require more frequent and larger applications of irri- 

 gation water than the lower lands. The water supply is sufficient for all till- 

 able lands. The climate is equable during the greater part of the year but 

 variable in spring and fall, although there is no extreme weather and winter 

 grazing of stock is practicable. There is some danger from frost on the upper 

 lauds. Arid or dry farming will probably not be successful on account of the 

 very low precipitation, varying from 6 to 142 in. at different places in the 

 reservation for the whole year and from 1.23 to 2.95 in. for the 3 months June 

 to August. 



The changes in cultivated soils, A. Mercier (Bnl. Soc. Chim. Belg., 19 {1906), 

 No. S-9, J). 261 ; abs, in Rer. Gen. Arjron., n. ser., 1 {1906), No. 2, pp. 56, 57).— 

 The author concludes from his studies that digestion with hydrochloric acid of 

 1.18 sp. gr. does not furnish any information of practical value as to the fertility 

 of the soil. In comparative tests of normal and tenth-normal hydrochloric acid 

 for this purpose the conclusion was reached that the normal acid is the strongest 

 which should be used for studies of this kind. 



The author concludes that all of the fertilizing material assimilable by plants 

 is removed in the first half liter of solution with acid of this sti-ength when 250 

 gm. of soil is used for extraction. The material removed by further treatment 

 is merely an indication of the changes in the soil. The apparatus used in the 

 extraction with acid is described. 



The amount and composition of the drainage through unmanured and 

 uncropped land, Barnfield, Rothamsted, N. H. J. Miller {Jour. Agv. HcL, 1 

 {1906), No. J,, pp. 377-399, fir/s. 4)-— I" this article a brief account is given of 

 the Rothamsted drain gages and the results obtained with them since their 

 establishment in 1870 are summarized. There are 3 of these drain gages 0.001 

 acre in area, extending to depths of 20, 40, and GO in., respectively. 



The annual averages for the 35 years, 1870 to 1905, were as follows : Rainfall 

 28.97 in. ; drainage— 20-in. gage 13.84 in., 40-in. gage 14.61 in., GO-in. gage 13.65 

 in. ; drainage per cent of rain — 20-in. gage 47.8, 40-in. gage 50.4, 60-in. gage 

 47.1 ; evaporation — 20-in. gage 15.13 in.. 40-in. gage 14..36 in., 60-in. gage 15.32 in. 



" The rain supplies annually to the soil about 5 lbs. of nitrogen. Of this 

 amount about 4 lbs. represent nitrates and ammonia which would be rapidly 

 nitrified in the soil, and the rest, about 1 lb., represents organic compounds 

 which may be either more or less readily nitrified than the organic nitrogen of 

 the soil. In any case the total amount is very small as compared with the 

 amounts found in the drainage through the soil of the gages. 



" During the last 28 years the average loss of nitrogen in the gages has been 

 31.4 lbs. per acre per annum. The annual losses vary from year to year con- 

 siderably, partly owing to differences in the rainfall and partly to the distribu- 

 tion of the rain. There is. in addition ... a slight tendency for the nitrates 

 to decrease, but this only manifests itself when successive averages of several 

 J ears are compared. The yearly amounts of nitrogen in the drainage of the 

 60-in. gage have varied from 61 to 15 lbs. with the highest recorded rainfall in 

 1878-9 (41.05 in.) and the lowest rainfall in 1897-8 (19.51 in.). Both years 

 >i-ere preceded by years of high rainfall. In 1898-9 when the rainfall was, for 

 a second year, unusually low, the 60-in. gage lost nearly 31 lbs. of nitrogen ; 

 and in 1899-1900 nearly 38 lbs. The very low results of 1897-8 are partly due 

 to the complete washing out to which the gages were pubjected the year befoi'e, 

 when the 60-in. gage lost 41.4 lbs. of nitrogen. It is probable, however, that 

 the 19 years between the maximum and niininnim losses have helped to increase 

 the difference." 



The average annual amounts of chlorin found in the drainage water during 

 28 years of observation were as follows : In the drainage water of the 20-in. 



