150 



B. LATHAM. Percolation, Evaporatiorrand Condensation. (Quart. 

 J. Roy. Met. Soc., 35 (1909), No. 151, pp. 189-211, figs. 8). Abs. 

 E. S. R., XXII, Jan. 1910. 



This article gives the results* of observations with rain gages 

 and percolating gages on chalk soils. 



Each of the percolating gages was exactly one square yard 

 (0.836 m. 2 ) in area and contained i cub. yd. (0.7645 m 3 ) of material. 

 The edges of the gages stood about i x / 2 in. (38.10 mm.) above the 

 surface of the soil inside and outside of the gage. One ,u;age was 

 filled with chalk soil, the other with a gravel soil containing vege- 

 table remains. The observations recorded began in 1878 and have 

 been continued daily up to the present time. The amount and 

 composition of the percolating waters and the evaporation as mea- 

 sured by standard evaporators are reported. The results are sum- 

 marized in the following table. 



Monthly average Rainfall, Percolation, Evaporation and Conden- 

 sation at Croydon, Surrey, in England, for the 30 years 1879 

 to 1908. 



