1917] SOILS — FEBTILIZEES. 621 



year's observations at Rothamsted on the dissolved oxygen content of rainfall 

 are reported and discussed, with descriptions of the apparatus and methods 

 used. 



The results show that rain water is very nearly saturated with oxygen 

 when the temperature of collection Is below 15° C, but is always below satu- 

 ration, occasionally as much as 25 per cent, when the temperature is above 15*. 



The coeflficient of correlation, W. G. Reed {Quart. Puts. Amer. Statis. Assoc, 

 n. ser., IS {1917), No. 118, pp. 670-684, figs. 4).— The limitations and applica- 

 bility of the coefficient of correlation as a measure of relationships, as, for 

 example, between July rainfall and yield of corn in Ohio, are discussed. 



" The coefficient of correlation is obtained by applying the least square adjust- 

 ment to all the material and is, therefore, the straight line of closest fit If the 

 relationship is not that of a straight line, it is obvious that the straight line of 

 closest fit is not a good measure of the relationhip and that some other 

 measure (e. g., the correlation ratio) must be used. Therefore, the coefficient 

 of correlation should never be used to show relationship until after the 

 phenomena have been investigated, at least far enough to show whether a 

 straight line satisfies the relationship as well as any other curve." 



The method of procedure to be followed in applying the method is explained 

 in some detail, and a bibliography of the subject is given. 



SOUS— feethizeks. 



Soil survey of Barbour C!o\inty, Ala., H. C. Smith, N. E. Beli,, and J. P. 

 Stboud {U. 8. Dept. Agr., Adv. Sheets Field Oper. Bur. 8oil^, 1914, pp. 50, fig. 



1, map 1). — This survey, made in cooperation with the State of Alabama, deals 

 with the soils of an area of 579,840 acres in southeastern Alabama, the topog- 

 raphy of which ranges from hilly and broken to nearly level. The drainage is 

 well developed. 



The area Is Included in the coastal plain province, and the soils are classed 

 as upland, stream terrace, and bottom-land soils. Including meadow, 23 soil 

 types of 13 series are mapped, of which the Ruston sandy loam, Norfolk sand, 

 and Ruston gravelly sandy loam cover 21.3, 14.3, and 10 per cent of the area, 

 respectively. 



Soil survey of Chickasaw County, Miss., E. M. Jones, C. S. Waxdbop, and 

 H. H. Bennett {U. S. Dept. Agr., Adv. Sheets Field Oper. Bur. Soils, 1915, pp. 

 S8, fig. 1, map 1). — This survey, made in cooperation with the State of Missis- 

 sippi, deals with the soils of an area of 320,640 acres in northeastern Missis- 

 sippi, the topography of which ranges from level or undulating to rolling or 

 hilly. Except in the Flatwoods section the drainage system of the county is 

 wqW developed. 



The upland soils derived from coastal plain deposits cover over three-fourths 

 of the area. The alluvial soils of the overflowed stream bottoms consist mainly 

 of silt and clay. Including chalk and rough gullied land, 24 soil types of 14 

 saries are mapped, of which the Lufkin silt loam, Oktibbeha clay, Ruston fine 

 sandy loam, and Lufkin clay cover 9.6, 9, 8.6, and 8.1 per cent of the area, 

 respectively. 



Soil survey of Anson County, N. C, E. S. Vanatta and F. N. McDowell 

 (77. S. Dept. Agr., Adv. Sheets Field Oper. Bur. Soils, 1915, pp. 65, pis. 7, figs. 



2. map 1). — This survey, made in cooperation with the North Carolina Depart- 

 ment of Agriculture, deals with the soils of an area of 344,960 acres in central 

 southern North Carolina, which lies on the boundary between the Coastal Plain 

 and the- Piedmont Plateau provinces. The topography is undulating to hilly. 



