818 EXPERIMENT STATION RECORD. 



when i)reseut in soluble form they prevented the l);ifterial decomposition of tho 

 phosi»boric acid. 



The successive stei)s in the solution or decomposition of the phosphoric acid 

 in bacterial cultures were as follows: (1) Generation of acids, (2) secondary 

 reactions in the solution, and (3) production of a soluble phosphorus-containing 

 organic substance. The first two of these are the results of the activity of 

 the bacteria on the phosphoric acid, and the last is due to the metabolic 

 assimilation of the micro-organisms. 



Bacterial activity as a corrosive influence in the soil, R. H. Gaines {Jour. 

 Indus, uitd Eitgiii. Clicm., 2 {I'JW), \o. -'/, pi). 12H-IS0). — From an examination 

 of samples of rust collected from pits in the outside and tubercles on the inside 

 of steel conduits in different parts of the country, the conclusion is reached 

 "that the corrosion of underground iron and steel structures is in part due to 

 bacterial activity: (1) Directly, or by the attack of a specific microbe; (2) 

 indirectly, or by creating acid conditions in the soil. Certain bacteria present, 

 owing to peculiar modes of absorption and elimination of sulphur and its com- 

 pounds, convert harmless substances into corrosive acids. 



"The remedies proposed are: (1) Free drainage, quiclvly carrying off the 

 acid solutions formed, should arrest or prevent destructive action; (2) in 

 localities or situations where drainage is impracticable, slack lime should be 

 packed about the metal, to neutralize acids formed as a result of bacterial 

 activity." 



Legume bacteria, S. F. Edwards {Ann. Rpt. Ontario Agr. Col. and Expt. 

 Farm, 35 {1909), pp. 131, i32).— About 2,000 cultures of legume bacteria were 

 distributed to farmers during 1909, and of 372 reports received giving the 

 results of their experiments, 56.7 per cent stated that benefit had been derived 

 from the use of the cultures. 



Methods of legume inoculation, K. F. Kellerman {U. S. Dept. Agr., Bur. 

 Plant Indus. Circ. 63, pp. 5). — This circular briefly points out the futility of 

 inoculating nonleguminous crops and gives directions for the soil transfer and 

 pure-culture methods of legume inoculation. 



A contribution to our knowledge of the nitrogen problem under dry- 

 farming, F. J. Axway and R. S. Trumbull {Jour. Indus, and Engin. Chan., 2 

 {1910), A'o. //. i)p. 135-138). — See an article previously noted ( E. S. R., 22, p. 

 221). 



The fertilizing influence of sunlight, E. J. Russell {Nature [London], 83 

 {1910), Ao. 2113, p. 2.^.9).— Referring to a previous note by Fletcher (E. S. R., 

 23, p. 222), the author questions whether the results obtained in experiments 

 on partial sterilization can be explained on the basis of the occurrence of toxic 

 substances in the soil as suggested by Fletcher. 



Soils and their fertility, J. H. Pettit {Successful Farming, 9 {1910), Nos. 

 3, pp. //6', .',7, flg. 1; Ji, pp. 3Jt-31, figs. 2; 6, pp. 26, 3Jf, figs. 2). — A general popular 

 discussion of the subject. 



In what does the fertility or sterility of the soil consist? J. Massart et 

 al. {Bui. 8oc. Cent. Forest. Belg., 16 {1909). No. 8, pp. Ji53-'i65, pis. 6).— 

 This is a discussion of the theory of soil fertility of the Bureau of Soils of this 

 Department. 



The principles of maintaining soil fertility, M. F. Miller {Missouri Sta. 

 Circ. 38, pp. n-.'i8. figs. 6). — This discussion, which applies particularly to 

 Missouri soils, deals with composition, deterioration, and improvement of soils, 

 and more particularly witli the use of various rotations and systems of cropping, 

 live stock, manures, and fertilizers in maintaining soil fertility. A system of 

 cropping for average soils in Missouri is suggested. 



