RECENT WORK IX A(;RIC11LTURAL SCIENCE. 



AGRICULTURAL CHEMISTRY. 



The rusting of iron, W. A. Tii.den (Jour. Cliem. 8oc. [London]. 93 (1908), 

 No. 549, pp. 1356-136',. flfj. 1; abft. in 8ci. Ahft., 8ect. A—Phyfi.. 11 (I90H), No. 

 131, p. 6^8). ^-Experimental evidence is presented to supiwrt the following con- 

 clusions : " ConmuTcial iron, liquid water, and oxygen are together suflicicnt 

 for the production of rust. Carbon dioxid is not necessary, but when i)r('S(Mit 

 hastens the action. Conunercial iron is attacked by pure water in the absence 

 of oxygen and carbon dioxid, the product being, not rust, but ferrous hydroxid. 

 Iron rust always contains ferrous oxid. The process of rusting is due initially 

 to electrolytic action resulting in the production of ferrous hydroxid or car- 

 bonate. This may be explained by the presence in all ordinary iron of various 

 components which afford surfaces at different potentials in the presence of 

 water, aqueous carbonic acid, or other electrolyte." 



Rusting of iron, J. N. Friend (Jour. Iron and Steel Inst., 77 (1908), pp. 5-32; 

 libs, in Sri. Ah.-i., Sect. A—Phys., 11 (190S), No. 131. pp. 6J,8, 6//,9).— The elec- 

 trolytic theory of corrosion of iron is held to be untenable. General rusting is 

 held to be primarily acid attack due to the presence of carbon dioxid with 

 moisture and oxygen. Cast iron only is attacked by pure cold or boiling water. 

 The purer forms of iron are not attacked by pure water and air or steam and 

 air at 100° C. The. corrosive action of rust is dependent upon its hygroscopic 

 nature, resulting in the absorption of moisture and carbon dioxid from the air 

 which continue the corrosion. 



Corrosion of iron, C. F. Burgess (Trans. Amer. Elcctrochcni. Soc, 13 (1908), 

 pp. 11-51,; (lbs. in Set. Abs., Sect. A—Phys., 11 (1908), No. 131, p. 6".J.S).— 

 Strained parts of mild steel corrode more rapidly than unstrained. Anneal- 

 ing at 900° C. removes this difference. Oxygen in boiler water promotes corro- 

 sion more than carbon dioxid. 



The principles and results of plant chemistry, I, H. Euler (Grundlagen 

 vnd Ergcbnissc drr Pflanzenchcmie. Brunsirick, 1908, pp. IX+238, dgm. 1). — 

 In this text-book, which it is stated is revised from the Swedish edition, present 

 knowledge regarding plant chemistry is summarized and digested. The princi- 

 pal subdivisions are nitrogen-free aliphatic compounds, nitrogen-free cyclic 

 compounds, and nitrogenous compounds. Full indexes add to the usefulness 

 of the volume. 



Concerning the value and synthesis of protein, F. Hofmeister (Arch. Expt. 

 Path. V. Pharmakol., 1908, Sup., pp. 273-281). — A digest of data on tlje structure 

 of the protein molecule. 



Milk proteins, G. A. Olson (Jour. Biol. Chcm., 5 (1908), No. 2-3, pp. 

 261-281). — Recent investigations on milk euzyms and proteolytic bacteria are 

 reviewed. The author foiuid in milk, cream, and butter a new protein, which 

 contains 18.93 per cent of nitrogen, gives a biuret reaction, and is dissolved in 

 weak sodium hydroxid solutions. It was first found in the filtrate of sepai'ator 

 slime after the casein and albumin had been removed, and can be isolated by 

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