SOILS FERTTTJZERS. 21 



In fTononil it is held tlinl " liiis ('.Npcriniciit slinws that tiiis soil is very 

 (li'ficieiit in av.-iihiiiU' iilidsplioric acid, and that as soon as this deficiency is 

 sniijilictl tiien tliere is a lacic of nitrogen and to a loss extent of i>otash also. 

 Wlicn conniicrcial fertilizers ;;i-(' relied n|Kiii entirely lo maintain a hi.t,di degree 

 of crop production a fertilizer containing' ail three constituents— niti'oj,'en. pot- 

 ash, and iiliosplioric acid — will .i,'ive hetter results than a fertilizer containint; 

 only one or two of these constituents. . . . 



" If le,i,'unnnons ci-ops .are raised and eithei' plowed under or f<Ml on the farm 

 .".nd the resultini; manure carefully saved and api)lied to the soil it is very 

 prohahle that in practice it will lie necessary to purchase only ])hosi)horic acid 

 in order to increase the productiveness of soils of this ty|)e and to maintain 

 them in a condition of hijih fertility. 



" Stable manure has demonstrated a.i;ain its .^reat \alue as .a restorer of fer- 

 tility to a poor worn-tmt soil." 



Results of cooperative experiments with fertilizers on swamp soils, 

 K. llAKcorirr (.1;/^'. h'lit. Onlaiio Aur. (iiid U.iiit. i'uhm. .il {1903). iip. 33-35). — 

 The results of 11 cooperative experiments with oats and 7 with corn on swamp 

 soil in different parts of Ontario are briefly reported. Potash (muriate) ])ro- 

 duced an increase in yield in every ease and Thomas slag gaA'e an increase in 

 every case except two, the increase being in every case sufficient to make the 

 use of fertilizers ])rotitable. 



Comparative tests of Peruvian guano and ammoniated superphosphate 9:9, 

 A. AuxsTADT (Itciil. L<iii(lir. /';r.s-.sc, JJ iJUdU). Xo. II), pii. J.')l>-I(il). — Experi- 

 ments of previous years (E. S. R., IG, p. 75S) were continued with oats and 

 fodder beets. The results for .3 years are partly summarized, showing a high 

 fertilizing value for the reru\ian guano as comi>ari'd with the annnonium 

 superphosiihate. 



The action of ammoniacal nitrogen as a fertilizer, T. Pfeiffer {Fuhlinfj's 

 Laiidir. Zt;/.. 'i.') ( HxiH), A o. .). //p. I.j3-1')'.) ) . — Various causes for the frequently 

 (tbserved inferioi'ity of annnoniacal nitrogen to nitrate nitrogen as a fertilizer 

 ;ii'e discussed. It is claimed that there are so many unknown factors causing 

 wide variations in the efficiency of ammoniacal nitrogen that the only safe plan 

 is for the farmer to make field exi)eriments to test the matter for himself. 



On the use of commercial nitrogen in connection with barnyard manure, 

 I'.ACiiMA.NX {Filhlimf.s Ldiiilir. Ztg., 5'> (JOOG), .Ao. ,'>. pit. 180-183). — The con- 

 ditions under which it is advisable to supplement farm manures with the more 

 active cummercial forms of nitrogen are discussed. 



The use of waste organic substances as manures, E. J. Russell (■/our. Bd. 

 .I,'//-. [ Lojiihiii]. 13 (inoii). \<K ,.-', jip. t;.',-ii2). — This article deals briefly with the 

 use as fertilizer of dried blood, feathers and feather waste, greaves (refuse 

 from making tallow or soap grease), hair, hoofs and horns, rabbit flick (rabbit 

 waste, consisting of ears. Xeet. tail, etc), slaughterhouse refuse, waste fish, 

 damaged oil cake, shoddy, refuse from tanneries, destructor refuse, night soil 

 and iiondrettc, and sewage sludge^-. 



Action of phosphoric acid on higher plants a.id a new nutritive solution, 

 C. voN DER Croxe (Iiiaii</. Diss. Bonn, lHo'i: \iiliinr. h'liml.'ichan. IDO.J, p. 2(>Ji ; 

 abft. in Ccnthl. Af/r. Clirin.. 3', (190G). A o. /. p/i. 30-33: .Jour. Chem. Soc. 

 \ Lotiihiii]. nil [lunr,]. \o. .'I'L II. lip. nil. /.''.'I.- W.iter cidture experiments 

 with diffi'rcid jiLants are reported which showed that when phasi)horic acid 

 was absent the I'oot (le\-eloi)ment was retarded and the roots wci-e yellow when 

 iron (as suli)hate) was i)res(>nt. The addition of phosphate precipitated the 

 iron and i)revenled its injurious action, but in this case the plants suffered 

 from chlorosis. (Jood results were obtained when ferrous phosphate and trical- 

 cium phosphate were added to the solution. When dicalcium phosphate was 



