266 



SCIENCE 



[N. S. Vol. XXXII. No. 817 



production of available nitrogen com- 

 pounds, and therefore the fertility. The 

 conclusion reached by Mr. Hall is that no 

 one factor can be found which determines 

 fertility; it must be taken as the resultant 

 of many and often conflicting actions. 



As is the case with so many other sec- 

 tions this year, joint meetings with the 

 representatives of other branches of sci- 

 ence form a prominent feature in the pro- 

 gram of the agriculturists. The object is 

 to obtain outside suggestions and criticisms 

 on questions that are now assuming con- 

 siderable importance in agricultural re- 

 search. Thus the question of magnitude of 

 error in an agricultural experiment will be 

 discussed in conjunction with Section F 

 (economic science and statistics), papers 

 being contributed by Messrs H. B. Arm- 

 strong, T. B. Wood, A. B. Bruce, R. W. 

 Berry, S. H. Collins, A. D. Hall and E. J. 

 Russell ; the question of soil surveys in con- 

 junction with Section C (geology), papers 

 being promised from the Rothamsted, Bris- 

 tol and Cambridge laboratories ; and the 

 question of the effect of organisms other 

 than bacteria on soil fertility in conjunc- 

 tion with Section D (zoology), papers by 

 Dr. E. J. Russell and Mr. W. B. Hutchin- 

 son. Probably the most popular subject 

 for discussion will be the growth of sugar 

 beet in England, on which papers have 

 been promised by Mr. G. L. Courthope and 

 Mr. Sigmund Stein. Some recent phases 

 of the problem of nitrogen fixation by bac- 

 teria will be discussed by Professor Bot- 

 tomley and Mr. John Golding. Among 

 individual papers, as distinct from contri- 

 butions to general discussions, may be men- 

 tioned "Scientific Breeding of Live 

 Stock," by Mr. K. J. J. -Mackenzie, of 

 Cambridge; "Effect of Town Atmosphere 

 on Vegetation, ' ' by Dr. Crowther, of Leeds ; 

 "A Bacterial Disease of Potatoes," by Mr. 

 A. Howe, of Armstrong College, Newcastle- 



on-Tyne ; and ' ' Costs of Danish Farming, ' ' 

 by Mr. Christopher Tumour. 



The program of Section C (geology) has 

 been arranged in some detail. Four papers 

 are announced for Thursday, September 1, 

 before the delivery of Dr. A. P. Coleman's 

 presidential address. These are "The 

 Yordale Series and its Equivalents Else- 

 where, ' ' by Mr. Cosmo Johns ; ' ' The Paleo- 

 zoic Rocks of Cantley (Sedbergh)," by 

 Dr. J. E. Marr, F.R.S., and Mr. W. G. 

 Pearnsides; "The Graptolitic Zones of the 

 Salopian Rocks of the Cantley Area (Sed- 

 bergh)," by Miss G. R. Watney and Miss 

 E. G. "Welch; and "Pleochroie Halos," by 

 Professor J. Joly, F.R.S. After the presi- 

 dential address papers will be read bj' Dr. 

 C. H. Lees, P.R.S., on "Mountain Temper- 

 atures and Radium"; Mr. F. D. Falconer, 

 "Outlines of the Geology of Northern 

 Nigeria"; Mr. W. Parkinson, "Notes on 

 the Geology of the Gold Coast"; and Mr. 

 Cosmo Johns, ' ' The Geological Significance 

 of the Nickel-Iron Meteorites." Friday's 

 proceedings will be devoted to joint discus- 

 sions with Section E (geography) on vari- 

 ous subjects of local interest. There will 

 first be a discussion on the geography and 

 geology of the Sheffield district, to which 

 contributions have been promised by Mr. 

 Cosmo Johns ("The Local Geology"), Mr. 

 H. Culpin ("The j\Iarine Bands in the 

 Coal Measures of South Yorkshire"), and 

 Mr. W. H. Dyson ("The Maltby Deep 

 Boring"). This will be followed by a dis- 

 cussion on the economic products of Shef- 

 field as affected by the structure of the dis- 

 trict. In this connection Professor A. 

 Mc William is expected to read a paper on 

 "The Metallurgical Industries in Relation 

 to the Rocks of the District." The re- 

 mainder of the day's proceedings will be 

 devoted to the consideration of regional 

 surveys. Papers have been promised by 

 Mr. T. Sheppard, on "The Humber during 



