508 Geological Society. 



3rd, In reviewing the nature of the peculiar glandular ap- 

 pendages that surround the large vascular canals of the 

 nautihis, I deem it an unfair inference to suppose that 

 they are the organs that secrete the fluid which circu- 

 lates in the siphuncular apparatus, seeing that the same 

 modifications of glandular structure exist in the dibran- 

 chiate cephalopods which are destitute of a siphoni- 

 ferous shell: the true function of these follicular bodies 

 is a physiological problem that yet remains to be 

 solved. 

 Nuneham House, Cheltenham, May 8th, 1838. 



LXXIX. Proceedings of Learned Societies. 



GEOLOGICAL SOCIETY. 



Anniversary Address of the Rev. W. Whewell, M. A., Y.W.'^., President. 



[Continued from p. 440.] 

 TN attempting a rapid survey of the contributions to geological 

 •*• knowledge which have come under our notice during the past 

 year, I may perhaps be allowed to advert to a distinction of the sub- 

 ject into Descriptive Geology and Geological Dynamics ; the former 

 science having for its object the description of the strata and other 

 features of the earth's surface as they now exist ; and the latter sci- 

 ence being employed in examining and reducing to law the causes 

 which may have produced such phsenomena. We appear to be directed 

 to such a separation of our subject by the present condition of our 

 geological studies, in which we and our predecessors have accumu- 

 lated a vast store of facts of observation, and have laboured with in- 

 tense curiosity, but hitherto with very imperfect success, to extract 

 from these facts a clear and connected knowledge of the history of the 

 earth's changes. Nearly the same was the condition of astronomy at 

 the time of Kepler, when the accumulated observations of twenty cen- 

 turies resisted all the attempts of that ingenious man and his contem- 

 poraries to construct a science of physical astronomy. But though 

 checked by such failures, they were not far from success ; and when for 

 the next succeeding century philosophers had employed themselves 

 in creating a distinct science of Dynamics, the science of physical 

 astronomy, full and complete, made its appearance, as if it were a 

 matter of course ; and thus showed the wisdom of separately cultiva- 

 ting the study of causes, and the classification of facts. 



DESCRIPTIVE GEOLOGY. 



If we begin with geological facts, our attention is first drawn to 

 that district on the earth's surface within which the facts have been 

 subjected to a satisfactory comparison and classification, which may 

 be considered, in a general way, as including England, France, Italy, 

 Germany, and Scandinavia. The language which the rocks of these 

 various countries speak has been, in a great measure, reduced to the 

 same geological alphabet. The questions of the determination of 



