408 SUMMARY OF WORK. 



crops of the several seams of coal were traced, and 

 the positions and effects of all the principal disloca- 

 tions were represented. The structure of the ground 

 was further displayed in a series of horizontal and 

 vertical sections, while additional details were given 

 in an excellent descriptive memoir, combining a com- 

 plete account of the stratigraphy and palaeontology 

 of the district. The lists of fossils, together with 

 plates of new species, form an important feature in 

 this publication. Not only were the organic remains 

 of the several formations discriminated, but even the 

 characteristic forms of successive horizons were dis- 

 tinguished, and the bearing of the palseontological 

 evidence on the geological conditions of deposit were 

 luminously discussed. This Coalbrookdale monograph 

 must be regarded as one of the classics of English 

 geology, marking a notable advance in the progress 

 of stratigraphy, and serving as a model for the sub- 

 sequent investigation of the geological structure of 

 our coal-fields. It appeared before the then recently 

 organised Geological Survey had mapped any of those 

 parts of the country, and it is remarkable how closely 

 the mapping of the Survey in subsequent years fol- 

 lowed the lines which he had laid down. 



But, unquestionably, the most important of Sir 

 Joseph's original contributions to science are to be 

 found in the series of papers which he wrote on 

 the older Tertiary formations of the south - east of 

 England, and on the younger deposits containing the 

 earliest traces of man. This brilliant work was begun, 

 carried on, and completed during the scanty intervals 

 of leisure which he could snatch from a busy mer- 

 cantile life. Properly to understand its scope and 

 value, we must go back to the earlier decades of this 



