28 EXPERIMENT STATION RECORD. 



Potassium sulphate at rates of 77.2 lbs. per acre, chlorid, 86.5 lbs., and nitrate 91.1 

 lbs., were each applied at the surface and at depths of 3, 6, and 9 in. to corn growing 

 in 3 ft. cylinders of marsh soil. From the results reported it appears that: 



"(1) The untreated soils have given yields only about one-half those from the 

 treated soils. 



"(2) While the yields on the untreated poorest soils are less in every case than 

 those from the better soil, the same amount of potash given to the poorer soil as that 

 given to the better has in nearly every case produced a larger mean yield than the 

 better soil did. 



"(3) The salts when applied at the surface have produced the least general 

 increase in yield, the 9 in. depth standing next, while the 3 in. depth has given the 

 largest general average. 



"(4) The data appear to indicate that the corn can not utilize the potash as well 

 for food when applied at the surface or 9 in. below as at intermediate depths, or else 

 that the salts exert an influence between 2 in. and 6 in. which is helpful in other 

 ways than as plant food." 



In experiments with potash salts on a variety of crops on marsh soils on 3 farms 

 in different parts of the State it was found that the potash salts were beneficial when 

 worked into the soils. 



On tlie absorption of monocalcium phosphate by arable soil and by humus, 

 J. DuMONT {Compt. Rend. Acad. Sci. Paris, 132 {1001), No. 7, pp. 435-437).— This 

 article reports tests of the absorptive power of different kinds of soil for monocalcium 

 phosphate by the following method: Fifty grams of the fine dry soil (passing a 

 1 mm. sieve) was shaken up with 350 cc. of a solution of monocalcium phosphate 

 containing 0.815 gm. of phosphoric anhydrid, and at intervals of from 2 hours to 15 

 days phosphoric acid was determined in 20 cc. of the solution. 



It was found that in humus soils containing variable amounts of lime, al:)Sorption 

 was greater than in ordinary soils and that removal of humus l)y incineration greatly 

 reduced the absorptive capacity. Apparently absorjition depends upon the relative 

 proportions of humus and lime, i. e., the greater the proportion of humus to lime, 

 the greater the absorption. 



The fixation of the phosphoric acid was not due exclusively to reversion, and an 

 abundance of humus reduced the amount of reversion. 



The chemical composition of Maryland soils, F. P. Veitch {Marijlund Sta. 

 Bid. 70, pp. 63-114). — This is a report on a chemical investigation of 60 samples of 

 soil rei:)resenting the typical soil formations of the State. The analyses were made 

 in the laboratory of the Division of Soils of this Department. The bulletin distrusses 

 the importance, object, and scope of soil work; the i)urpose and methods of chem- 

 ical examination of soils; describes the samples, and discusses their classification with 

 reference to geological formations, typical crops, and chemical and mechanical com- 

 position. In the chemical examination of the soils 3 methods were used, (1) fusion 

 method,' (2) concentrated (1.115 sp. gr. ) hydrochloric acid method,^ and (3) fifth- 

 normal hydrochloric acid method.^ The average results obtained with the different 

 classes of soils are given in the following table: 



1 Bui. U. S. Geol. Survey, 148. 



''U. S. Dept. Agr., Division of Chemistry Bui. 46, revised. 



