426 Progress in Science. [July, 



Agricultural Geology and Geological Maps. — The relation between Agricul- 

 ture and Geology is a significant fact, and has been brought prominently into 

 notice in the description of many parts of Great Britain, in the " Journal of 

 the Royal Agricultural Society," and in the " Bath and West of England 

 Agricultural Society." Mr. Topley, F.G.S., has communicated to the first- 

 mentioned Society a paper on the " Comparative Agriculture of England and 

 Wales," in which he gives a table showing the percentage of each crop to the 

 total acreage of each county, and then traces out the relations of geological 

 structure and contour to Agriculture. Classifying the English counties ac- 

 cording to their leading features, he remarks that the western part of the 

 country contains the largest portion of high land, and that this higher western 

 land is occupied by the older geological formations. The greatest rain-fall is 

 over this area, and, speaking generally, over other districts the fall is in pro- 

 portion to the height of the ground. Summer temperature is of great 

 importance ; this is highest over the eastern central district. Considered 

 agriculturally, the western counties are characterised by their large acreage of 

 grazing land, whilst in the eastern there is a high percentage of corn land. 

 There is thus a general coincidence between geological structure, contour, 

 climate, and agricultural products. These four classes are stated by Mr. 

 Topley to be of importance in the order here given ; each is controlled by the 

 one that precedes it. Agriculture depends mainly on climate, climate mainly 

 on contour, and contour mainly on geological structure. 



Agriculture is of course closely related to Geology, in regard to soils, which 

 depend so much upon the underlying rocks ; but whilst such extensive systems 

 of draining and manuring are now carried on, the character of the crops is not 

 so dependent upon the natural soil as it used to be. Nevertheless, maps 

 showing the superficial deposits, the gravels, drift clays, and loams, will be of 

 great service to the agriculturist, and it can be little estimated — when glancing 

 at our ordinary geological maps, where these deposits are omitted — what a 

 vast difference their insertion makes. The publication of maps showing the 

 superficial deposits has been commenced by the Geological Survey, in parts of 

 Buckinghamshire, Hertfordshire, Middlesex, and Essex, included in their 

 Sheets Nos. 1 to 7. These drifts or superficial deposits comprise the Boulder 

 clay, and various gravels and brick-earths of different ages, also the clay-with- 

 flints of the chalk districts. 



Mr. Topley has given a sketch of the Agricultural Geology of the Weald in 

 the last volume of the " Journal of the Royal Agricultural Society." His 

 paper is accompanied by a coloured map showing the geology of the tract and 

 the prevailing soils. 



One of the recently-published maps of the Geological Survey of England is 

 Sheet 64, which includes the county of Rutland and parts of Leicester- and 

 Northampton-shires, and displays, in its geological structure, the Lias, the 

 Lower and Middle Oolitic rocks, and a portion of the Fenland. This area has 

 been surveyed by Mr. J. W. Judd, F.G.S., and until he gave his attention to 

 the elucidation of the Lower Oolitic rocks of this much-neglected country 

 much confusion existed about their classification. The conclusions at which 

 he has arrived have been confirmed by Mr. Sharp, whose papers were referred 

 to in our last report of Geological Progress. 



Geological Diagrams. — Two Tables of British Strata, by Mr. H. W. Bris- 

 tow, F.R.S., Director of the Geological Survey of England and Wales, have 

 lately been published. The one is a classificatory table, showing the subdivi- 

 sion of the rocks and their local modifications : it contains also an account of 

 the geological distribution of the different groups of life, by Mr. R. Etheridge, 

 F.R.S. The other table is a coloured one, showing the relative thickness of 

 the different geological systems, formations, and the minor subdivisions — a 

 feature of great importance in a lecture- or school-diagram. 



Mr. Topley, F.G.S., and Mr. J. B. Jordan have been constructing a series of 

 geological models of England and Wales, on the scale of 4 miles to 1 inch 

 horizontal, and 2000 feet to 1 inch vertical. There will be eighteen blocks, 

 each about 25 inches by 17 inches in size, and they will show clearly the phy- 

 sical features and the geology of the country, which will be of great service 



