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The characteristics of this very peculiar soil, its prevailing weeds, 

 and most important Silva and Flora, its average depth, nature of 

 surface, effects upon it of rain and of drought, the form of its water- 

 courses, and general conditions affecting the cotton plant are carefully 

 described, and their bearings on the subject discussed. The exami- 

 nation of these soils was twofold physical or chemico-physical, 

 and purely chemical or analytical. The methods employed in each 

 are detailed ; and in the former, those of Schubler and of Schulze, 

 with modifications by the author, were principally employed, atten- 

 tion being also given to the methods and results of Liebig's recent 

 experiments, and those of others, on the power of withdrawal by soils 

 of saline and other substances from their solutions. The external 

 characters of the soils examined are then described ; the real or 

 true specific gravity, and the weight of a given volume in 

 known conditions of moisture and dry ness the contraction in volume 

 on drying from a determinate extreme of wetness the cohesion of 

 the soil, or adhesion of its particles (in known conditions as to 

 moisture) to each other, are all determined, the last by a method 

 believed new. The adhesion of these soils to the surfaces of iron 

 implements, as ploughshares, hoes, &c., was ascertained in the state 

 of "maximum moisture," as proposed by Schubler, of whose method, 

 however, the author expresses some disapproval. 



The next physical condition determined is the absorption of heat 

 from the sun's rays, with tabulated results, both for the absolute 

 maximum temperature attained ; and the rate at which the increment 

 takes place. The results indicate the importance of noting the latter, 

 and prove that the statements of Malaguti and Durocher, in opposi- 

 tion to Schiibler, that mineral composition has a more important 

 influence than colour upon the thermo-absorptive capacity, and that 

 of sand is greater than that of clay, must be accepted with consider- 

 able limitations. Conversely, the author has determined the relative 

 retentive powers of these soils for heat, having intimate relations 

 with the rate at which they lose heat after the sun has become ab- 

 sent, and tabulated his results, which differ considerably, as he 

 notices, from those of Schubler in analogous cases, the discrepan- 

 cies remaining after repetition, by the author, of his own experi- 

 ments. He points out some of the probable causes of this. 



He then proceeds to the power of absorption and retention of 



