428 EXPERIMENT STATION RECORD. 



oration l)y the plants as inflnenced by light, period of vegetation, hnuiidity of the 

 soil and air, etc. 



(4) In order to measure the accumulation, evajioration, and percolation of water 

 in the soil it is necessary to have recourse to lysimeters. If it is desirable, in addi- 

 tion, to trace the movement of the water under the influence of capillary forces, 

 difference of temperature, etc., from the higher to the lower layers, and vice versa, 

 there remains one of two ways open, either to construct a segmented lysimeter, con- 

 sisting of a series of cylinders (each capable of being weighed separately) filled with 

 the given soil and subsoil, or to determine the moisture by taking samples of the 

 whole depth of the layer under investigation. 



(6) The determination of the moisture of the arable soil layer at various stages of 

 culture is possible only by taking samples for the estimation of moisture, or, perhaps, 

 by measuring the electric conductivitj; of the soil as described in some recent inves- 

 tigations, for the determination of the moisture of the cultivated soil layer can not 

 be made with any degree of accuracy either by means of the evaporometer or by the 

 aid of a weighed lysimeter. — p. fireman. 



New evaporometer for the study of the evaporation from ^rass, and obser- 

 vations with it in the Constantine observatory in 1896, 'SI. Rikaciiev {Ahs. 

 in Zltur. Opuiin. Agron., 1 {1900), No. 1, pp. 115-117). — The apparatus is claimed to 

 be better adapted than others which have been proposed for the study of evapor- 

 ation from various cultivated plants and soils under the influence of different 

 meteorological, soil, and culture conditions. The evaporometer consists of three 

 rectangular zinc boxes, of which the outer one is placed in the ground, while the 

 other two, one above the other, are fitted tightly into the first one. The lower box 

 of the last two has an entire bottom and shoulders projecting inward, while the 

 upper one has a bottom with perforations 1 cm. in diameter, separated by distances 

 of 1.5 cm. The upper box rests on the shoulders of the lower one. The upper box 

 is 40 cm. long, 25 cm. wide, and 15 cm. deep. The length and width of the lower 

 one are the same, but the depth is only 10 cm. The area of the inclosed space is 

 about 1,000 sq. cm. In order to make observations with* the apparatus, water is 

 poured into the lower box until it forms a laver 5 cm. deep, and a thermometer 

 is placed in the apparatus on supports provided for it. The upper box receives on its 

 perforated bottom first a layer of coal 1 cm. thick and then a piece of sod cut to 

 closely fit the box. Experiment showed that a piece of sod retained its fresh appear- 

 ance during 3 months without the application of water. Into the sod a thermometer 

 is introduced so that its bulb is buried to a depth of 10 cm. The whole apparatus, 

 together with the Sfxl and water, weighs about 24 kg. When it rains the excess of 

 water percolates into the lower box. The presence of water here must, according 

 to the author, maintain a constant degree of humidity in the lower layer of the 

 upper vt^ssel. Observations were made 3 times every day, for which purpose both 

 inner boxes were taken out and weighed together, the temperature of the sod taken, 

 the upper box removed, and the temperature of the water taken. The decrease of 

 weight between two observations was taken as a measure of the evaporation from the 

 sod during that time. When the midday observation was made the lower ves.sel 

 was also weighed separately, and if an increase of water caused ])y a rain was noticed, 

 the excess was poured off, leaving a layer of water weighing 4,410 gm, (5 cm. deep). 



The evaporation from sod as measured by this apparatus exceeds that found by 

 Wild's evaporometer 2 to 3 times. — p. fiheman. 



Solution studies of salts occurring in alkali soils, F. K. Cameron, L. J. 

 • Briggs, and A. Seidell ( V. S. Depf. Agr., Division of Soils Bui. IS, pp. 89, figs. 10). — 

 This is a series of technical papers giving preliminary accomits of studies made dur- 

 ing the past year. Investigations are reported on the equilibrium between carbon- 

 ates and bicarbonates in aqueous solutions, in which it is shown that when in 

 equilibrium with the air aqueous solutions of sodium or potassium normal carbonate 



