SOILS FERTILIZERS. 531 



SOILS FERTILIZERS. 



AgricultuVal charts at the Congress of Applied Chemistry, Rome, 1906 

 {Rev. Gen. Aiiroii.. n. xcr.. I (1!)06), A o. H-l. p/i. 2o'i-2.')6). — This is ii review of 

 a discussion of tiiis subject by Troosf. 



Tlie relation of plnnts to the composition of tlie soil .-iiid the nssocintion of 

 certiiiu plnnts with a particular kind of soil under natural conditions are dis- 

 cussed with reference to the utilization of such knowledse in the preparation 

 of agricultural charts. A permanent committee of si)ecialists in various lines 

 was appointed to take this subject under consideration and to comi)ile materials 

 for the preparation of such charts. 



On the relation between soils and the rocks from which they are derived, 

 L. Milch {Mitt. Landic. Inst. Brcslaii. .i (HlOi;). Xo. 3. pp. 867-897). — The 

 studies here reported of soils produce<l under natural conditions at different 

 stages of weathering from rocks of various kinds led to the i-onclusion that from 

 the standpoint of soil foi'matiou the mineralogical constitution is the most im- 

 portant characteristic of the soil-forming rocks; that sinnlar rocks may often 

 in the course of weathering yield very dissimilar soils and vice versa, for ex- 

 ami)le. such petrogenetically dissimilar rocks as granite and metamorphosed 

 gneiss may at certain stages of decomposition yield like soils, and that the 

 tendency is iu all eases toward final uniformity of decomposition products and 

 similar soils even when the original rocks were of very different character. 



Oxidation in soils and its relation to productiveness, F. V. Darbishire and 

 E. J. Russell {Chem. News, DJf {1906), No. 2Ji-'f3, p. 137).— \ brief abstract of 

 a paper read before the 1906 meeting of the British Association at York (see 

 also E. S. R., 17, p. 536). 



The phospho-humic compounds of the soil, J. Dumont (Compt. Rend. Acad. 

 Nr/. \l'(iris\. l',.i (191)6). Xo. 3. pp. 186-1S9: nhs. in Jour. Chem. Soe. [London]. 

 9U {191)6). No. .')27, II, p. 626). — The author briefly reports the results of experi- 

 ments in precipitating alkaline humate in the presence of solutions of i)hos- 

 phoric acid and phosphates and deternnning the composition of the precipitate. 



He concludes from the results obtained that well-defined phospho-humic com- 

 pounds are formed partly by the absorbent action of hunms on the soluble plios- 

 I'hates in the soil solutions and ])artly by the reaction of these phosphates on 

 the alkalint' humates naturally iiroduced by chemical action in cultivated 

 soils. 



Potassium iium;ite absorbed (>.l jier cent of jihosidioric acid when treated with 

 a solution of this sul)stance and larger anumnts when treated with a solution of 

 monocalcium phosphate. Ilumus precipitated in ])resence of dipotassium phos- 

 phate by a number of different acids contained about the same amount of phos- 

 phoric acid in each case and the percentage of this substance remained con- 

 stant whatever the excess of ])hosphate added. 



Studies on the soils of the northern portion of the great jjlains region. 

 The second steppe, V. J. Alway (.\)n<r. Cliein. Jour.. 36 {1906), No. 6. pj). 

 ■')S0-.')9.'t). — The region referred to in this article " includes the whole eastern 

 portion of the great plains, properly so-called, of Canada," of which I1h> aver- 

 age elevation is 1,(500 ft. 



Analyses of samples of each foot of the soil down to a dei)th of <> ft., taken at 

 the Indian Head experimental farm, are rei)orted. and while these analyses 

 show the soil to be fertile, it is stated that there is nothing in the analytical 

 results to explain the remarkable yields of wheat, oats, barley, peas, and 

 potatoes which have been obtained. 



