356 SUMMARY OF CAREER CHAP, xi 



to-day, coming with all the appliances of modern 

 petrography, may be able to improve the nomen- 

 clature followed by Ramsay, and to show that he had 

 been mistaken in some of his determinations, as 

 where, for instance, he may have classed lavas as tuffs, 

 or tuffs as lavas. The surprise ought rather to be 

 that a man with only field-evidence and his geological 

 instinct to guide him, should have succeeded in un- 

 ravelling so admirably the complications of so difficult 

 a region. 



British geology lies under a deep obligation to 

 Ramsay for the skill and insight with which he 

 deciphered the relics of the older Palaeozoic volcanoes. 

 Without attempting to enter into the minutiae of the 

 mineralogical and chemical constitution of the rocks, 

 he seized upon the salient features that illustrated 

 ancient volcanic action, and he supplied, in the Survey 

 Memoirs and in the Descriptive Catalogue of the 

 Jermyn Street Museum, the first detailed and con- 

 nected description of the different epochs of volcanic 

 activity in the Silurian period in Britain. 



On the maps and sections of the Geological 

 Survey he expressed most of his results in structural 

 geology, and it may be fearlessly asserted that at the 

 time of their appearance these publications were un- 

 surpassed for clearness, beauty, and accuracy. Even 

 where the mapping was mainly the work of his col- 

 leagues, it usually had the benefit of help from his 

 skilful hand and sound judgment. His Geological 

 Map of England and Wales, reduced from the Survey 

 sheets and other sources of information, is still the 

 most useful small map of the kingdom, and his 

 general Geological Map of the British Isles is a con- 

 venient compendium of British geology. 



