AGEICULTUEAL CHEMISTKY — AGROTECHNY. 611 



taiued from the soil has the properties of metaoxytoluic acid, with the car- 

 boiyl, hydroxyl, and methyl radicals in the 1. 3. 5. positions, respectively. 

 . . . Metaoxytoluic acid was made from sulphotoluic acid according to the 

 method of Jacobseu, and its properties were compared with the compond ob- 

 tained from the soil, the two agreeing in every res^)ect." Vanillin was isolated 

 and the amount present, as noted by the Folin and Denis method (E. S. R., 

 28, p. 807), was determined. "Sample No. 1 gave 0.001 per cent of vanillin, 

 or 10 parts per million, while sample No. 2 showed 0.00048 per cent, or 4.8 

 parts per million." 



In some previous work (E. S. R., 24, p. 524) it was shown that the methoxyl 

 radical was present in many soils and could be determined by the Zoi.sel method. 

 "A determination of the methoxyl in samples Nos. 1 and 2 by this method gave, 

 for sample No. 1, 0.0G5 per cent of methoxyl calculated to vanillin, and for 

 sample No. 2, 0.05 per cent." As the quantity of vanillin calculated was very 

 much in excess of that isolated from an alkaline extract or that indicated by 

 the Folin and Denis method it is probable that a considerable portion of it 

 originates from compounds other than vanillin. 



Of the three substances isolated, only benzoic acid and vanillin are naturally 

 occurring products. The three substances, however, may be derived from, or 

 transformed into one another. The preparation of metaoxytoluic acid in the 

 laboratory does not suggest any process by which it may be formed in the soil 

 from plant products or other compounds known to occur in soils. " Using the 

 maximum figures for quantities obtained in these investigations and calculat- 

 ing to the acre-foot of soil, the following approximate quantities are obtained : 

 Benzoic acid, 350 lbs. ; metaoxytoluic acid, 800 lbs. ; and vanillin, 40 lbs. to 

 the acre-foot. In the case of the two acids the method involved considerable loss 

 of material and the actual quantity present in the soil is undoubtedly in excess 

 of these figures. 



" The question as to the form In which these compounds exist in the soil is 

 one deserving some consideration, although one not easily answered satisfac- 

 torily. It is true of most organic compounds that have been obtained from 

 soils through extraction with dilute alkali that they are not readily obtained as 

 such by water extraction of the soil. In many soils this can be expained, in 

 part at least, by the fact that much of the organic matter in soils is of a 

 resinous nature wholly insoluble in water, and compounds which when sepa- 

 rated are easily soluble in water are so incased or protected by the resinous or 

 varnishlike coating effected by this resinous material that they are very slowly 

 dissolved, if at all, when the soil is leached. This effect is quite apart from 

 any absorptive effect and is quite marked in extreme types, such as the sands 

 of Florida and some peats, where either fine grinding or previous treatment 

 with alcohol will render soluble in water organic material that before this 

 treatment was so little soluble as to escape notice." 



The methods utilized in the study are given in detail and are discussed. 



The mineral elements contained in the casein of milk, L. Lindet {Orig. 

 Commun. 8. Internat. Cong. AppL Ghem. [Washington and New York], 19 

 {1912), Sect. Vllld, pp. 199-207; Compt. Rend. Acad. Sci. [Paris], 155 {1912), 

 A"o. 19, pp. 923, 924; abs. in ZentU. Biochem. u. Biophys., 14 {1913), No. 17-18, 

 p. 615). — In this paper it is shown that only about half of the i>hosphorus 

 contained in casein and obtained by precipitation with rennet is present as a 

 calcium phosphate (probably a tricalcium phosphate), and that the remainder 

 is present as a phosphoric acid compound of casein which is easily hydrolyzed 

 with an alkali. Three-fifths of the calcium is bound to the phosphoric acid 

 and the remaining two-fifths to the casein. 



