24 AUTOBIOGRAPHY. [Ch. II. 



the commencement of 1831 ; and Henslow then persuaded me 

 to begin the study of geology. Therefore on my return to 

 Shropshire I examined sections, and coloured a map of parts 

 round Shrewsbury. Professor Sedgwick intended to visit 

 North Wales in the beginning of August to pursue his famous 

 geological investigations amongst the older rocks, and Henslow 

 asked him to allow me to accompany him.* Accordingly he 

 came and slept at my father's house. 



A short conversation with him during this evening produced 

 a strong impression on my mind. Whilst examining an old 

 gravel-pit near Shrewsbury, a labourer told me that he had found 

 in it a large worn tropical Volute shell, such as may be seen 

 on chimney-pieces of cottages ; and as he would not sell the 

 shell, I was convinced that he had really found it in the pit. I 

 told Sedgwick of the fact, and he at once said (no doubt truly) 

 that it must have been thrown away by some one into the pit ; 

 but then added, if really embedded thore it would be the 

 greatest misfortune to geology, as it would overthrow all that 

 we know about the superficial deposits of the Midland Counties. 

 These gravel-beds belong in fact to the glacial period, and in 

 after years I found in them broken arctic shells. But I was 

 then utterly astonished at Sedgwick not being delighted at so 

 wonderful a fact as a tropical shell being found near the surface 

 in the middle of England. Nothing before had ever made me 

 thoroughly realise, though I had read various scientific books, 

 that science consists in grouping facts so that general laws or 

 conclusions may be drawn from them. 



Next morning we started for Llangollen, Conway, Bangor, and 

 Capel Curig. This tour was of decided use in teaching me a 

 little how to make out the geology of a country. Sedgwick 

 often sent me on a line parallel to his, telling me to bring back 

 specimens of the rocks and to mark the stratification on a map. 

 I have little doubt that he did this for my good, as I was too 

 ignorant to have aided him. On this tour I had a striking 

 instance how easy it is to overlook phenomena, however con- 

 spicious, before they have been observed by any one. We 

 spent many hours in Cwm Idwal, examining all the rocks with 

 extreme care, as Sedgwick was anxious to find fossils in them ; 



* In connection with this tour my father used to tell a story about 

 Sedgwick : they had started from their inn one morning, and had walked 

 a mile or two, when Sedgwick suddenly stopped, and vowed that he would 

 return, being certain " that damned scoundrel " (the waiter) had not given 

 the chambermaid the sixpence intrusted to him for the purpose. He was 

 ultimately persuaded to give up the project, seeing that there was no 

 reason for suspecting the waiter of perfidy. — F. D. 



