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THE 



QUARTERLY JOURNAL 



GEOLOGICAL SOCIETY OF LONDON. 



EDITED BY 



THE ASSISTANT-SECEETAEY OP THE GEOLOGICAL SOCIETr. 



Quod si cui mortalium cordi et curse sit non tantum inventis haerere, atque iis uti, sed ad ulteriora 

 penetrare ; atque non disputando adversarium, sed opere naturam vincere ; denique non belle et probabiliter 

 opinari, sed certo et ostensive scire; tales, tanquam veri scientiarum filii, nobis (si videbitur) seadjungant. 

 —Novum Organum, Prcefatio. 



VOLUME THE FORTY-SECOND, 



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MDCCCLXXXVr. 



