On the Agricultural Geology of England and Wales. 451 



tlie questions so interesting- in tlieoretical geolojry, and on which the 

 study of organic remains has thrown so much light respecting 

 the ancient changes of the earth and its inhabitants. Tiie in- 

 formation, therefore, which agriculture requires of geology is pre- 

 cisely that of which geological maps, as at present constructed, 

 and the present prevalent course of geological inquiry furnish 

 the least. 



Rise and Progress of Agricultural Geology — prohahle Cause of 

 this Defect. — During the half-century which has elapsed since 

 geology has risen to the rank of a science of observation and in- 

 duction, from being a mere mass of crude speculations, little pro- 

 gress has been made in its practical application to agriculture, 

 chiefly because farmers have not been geologists, and geologists 

 in general have been ignorant of agriculture. Whenever a step 

 has been gained, it has been by the union of the two kinds of 

 knowledge in one individual. The yeoman and land-surveyor of 

 Oxfordshire who ranks as the father of English geology was also 

 the first to apply it to agricultural questions. 



Professor Sedgwick has observed of him, that he furnishes an 

 instance of the manner in which things inconsiderable in them- 

 selves act on certain minds so as to influence the whole tenor of 

 afterlife. Born in an oolitic district rich in fossils, which were 

 the playthings of his childhood, he was led by them, while em- 

 ployed as a land-surveyor on the outcrop of the strata in central 

 and southern England, to habits of observation, which terirnnated 

 in his three great discoveries — that strata have an invariable 

 order of succession ; that each has been successively, and for a 

 long time, the bed of the sea ; and that each possesses a peculiar 

 group of organic remains, by which, in the absence of other evi- 

 dence, its place in the series may be determined. To the con- 

 templation of his favourite oolites, on which he was born and 

 lived, and on which he wished to be buried, we may trace a sliirht 

 oolitic hue both in his geology and in its application to r^^ricui- 

 ture. The oolites of the south of England are more subdivided 

 than elsewhere, and some of the subdivisions are characterised by 

 peculiar species. It was natural, therefore, that his studies should 

 receive a local impress, and that a local truth should be some- 

 what over-generalised by him. As observations multiplied and 

 the science advanced, it was found that these minute distinctions 

 could not be relied on, be3^ond certain limits, and that in the 

 identification of strata we must look to broad features, to groups 

 of fossils, as characterising groups of rocks. While the organic 

 group, as a group, is constant under variations of mineral com- 

 position, mineral characters modify the distribution of its compo- 

 nent parts, just as deposits now forming beneath the sea exhibit 

 collectively the general assemblajye of organic bodies now in 



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