Reviews — Geology and Agriculture. 377 



of Gloucester, Hereford, Shropshire, Worcester, and Warwick, remain 

 in the ' fictitious ' condition. 



In the First Report, before mentioned, it was stated that " The 

 geological map of the country furnishes the only possible basis for 

 a classification and survey of its soils, at any rate, as far as the 

 preliminary work goes ". In the present work Mr. Hall observes 

 (p. iv), " It will be seen that we have taken the geological formations 

 as the basis of our work, and have assumed that each formation 

 represented in the district will give rise to a soil-type which can be 

 characterised both by its mechanical analysis and by special features 

 in the farming which prevails over its outcrop. The justification for 

 these cardinal assumptions was obtained in the early stages of the 

 work by following the dividing line representing the outcrop of two 

 formations, and finding (1) that the dividing line held for the soils as 

 well as for the under! ying formations ; (2) that the soils from any 

 formation (with one or two exceptions) did show on analysis certain 

 common features which marked them off from other soils. These 

 conclusions have been strengthened as our work proceeded ; all our 

 experience in the field goes to show that each formation in the area 

 under consideration gives rise to a distinct soil-type, the characteristic 

 composition of which can further be recognised by making up an 

 average from the mechanical analyses of the samples taken from that 

 formation." 



Allowances, of course, have to be made in all cases for wind-drifted 

 or other adventitious material in the soil, and for downwash on slopes. 

 The above quotation, however, shows the importance of a careful 

 detailed geological (or subsoil) survey. 



The Geological Survey has indeed done more for the district than 

 Mr. Hall appears to know, as new series 1 inch Drift maps, K"os. 317 

 (Chichester and Midlmrst), 332 (Bognor, Selsey, and Littlehampton), 

 333 ( Worthing and llottingdean), and 334 (JNewhaven and Eastbourne), 

 have been published, and manuscript copies of 6 inch maps of the 

 areas have been deposited for public reference in the Library of the 

 Museum of Practical Geology. 



It is therefore all the more remarkable that the results obtained by 

 careful soil-investigation over areas represented for the most part by 

 the older Drift maps of the Geological Survey have led to conclusions 

 which we are justified in considering as far-reaching. 



Similar results were notified in the Vale of Belvoir and bordering 

 tracts by Mr. G. W. Lamplugh, 1 who had the advantage of some 

 discussion on the ground with Mr. Hall and Professor T. H. Middleton. 

 There it was found that "The geological boundaries conform fairly 

 well to the varied character of the soils and subsoils, though the 

 margins of the superficial deposits are rarely so sharply defined as the 

 lines necessarily drawn for their delimitation on the map might seem 

 to imply ". We have dwelt at length on these matters because it may 

 now be considered as demonstrated that a careful detailed geological 

 map of all the exposed formations (Drift and Solid) is of essential 

 service to the agriculturist. 



1 Geology of the Melton Moivbray District, etc. (Mem. Geol. Surv., 1909), p. 99. 



