350 P. W. Stuart- Menteath — On the Pyrenees. 



and ophite, and that his supposed proofs of the Jurassic age of the 

 latter are the illusions which Pyrenean geologists have long main- 

 tained them to be. The traditions of Pyrenean exploration since 

 1819, which are more important than any published work that 

 M. Lacroix has utilized, have as usual ended by removing the 

 illusion of first impressions in his case. 



M. Carez, who conducted the excursion of more strictly geological 

 interest, similarly admits the contrary of what he has previously 

 maintained during many years, but unfortunately he had not time 

 to apply his conversion to the details of the extensive ground with 

 which he deals. A confused and contradictory impression was 

 hence inevitable regarding the most accessible, most typical, and 

 best exposed mountain chain in Europe. Had Pyrenean geologists 

 taken any part in the work of the Congress, this confusion would 

 have been removed by the pointing out of decisive facts which have 

 been ignored in attempts to controvert their results and to supersede 

 their traditions. Practice, as opposed to theory, would have been 

 confirmed in a fashion detrimental to the present attempt in Paris to 

 substitute the theories of Suess for those of Elie de Beaumont and 

 D'Orbigny, which during thirty years enabled Parisian geologists 

 to dictate the results admissible from every local observer. The 

 earlier theories perished through the death of their influential 

 supporters, and because their mathematically definite outlines placed 

 them in sharp opposition to observed facts. The latter disadvantage 

 has been obviated in the more ingenious conceptions of theorists who 

 are usually successful in avoiding any appeal to decisive facts. 



The detailed map and sections presented by M. Carez in the 

 Livret Guide are slightly modified reproductions of the work of 

 Pyrenean' geologists, selected at those points which have been most 

 completely described and figured by them in print; but these 

 documents were produced many years ago, and are not completed 

 by even the additional facts of observation which were known to 

 their authors in 1866, when I commenced the natural development 

 of their work with their assistance and co-operation. Thus, at Salies 

 du Salat the detailed map presented is arranged to produce the 

 belief that no granite exists in the Cretaceous and that the salt 

 deposits belong to the Trias formation, in accordance with theories 

 which M. Carez has opposed to nearly all the authors of serious 

 mapping in the Pyrenees. Yet for many years past I have several 

 outcrops of granite marked on my working maps, and these have 

 been described by Leymerie, Garrigou, Bleicher, and Pouech. 

 Immediately in front of the bridge by which the excursion left 

 the town of Salies the granite is visible to right and left for over 

 200 metres between Bout du Pont and the Salt Factory; and to 

 the east, between Betchat and Jourdin, it forms bosses of 50 metres 

 in diameter, well exposed on the left bank of the Lens stream. 

 If any foreign geologist will visit these points he will understand 

 the character of the assertions by which M. Carez has nullified the 

 work of all Pyrenean geologists during the last twenty years. 

 M. Eoussel has recently admitted the presence of the intrusive 



