INTRODUCTION- 



IX 



an 



ical 

 sin 



Ing- 



med 

 me; 

 litic 

 con- 

 ales, 



lard 

 larl, 

 and 

 and 

 and 

 the 



iles; 

 ecu- 

 ding 



ocks 



aens 



i. 



Hus- 

 ring 



the 



In the other cases in the galleries of the Museum 

 devoted to the collection of fossils the student will 

 frequently find illustrative specimens of rocks. The 

 specimens containing fossils of themselves give a good 

 idea of the nature of the different formations, and 

 may be regarded as a kind of stratigraphical collec- 

 tion of rocks. In these cases, and the catalogue which 

 explains them, he will also find a description of the 

 fossils and of the order of their succession in all the 

 British formations. 



The collections of ores and other minerals in the 

 principal floor show the economic substances pro- 

 duced by the rocks. Together, they form a kind of 

 hand-book to British geology, which will be more 

 complete if space is ever afforded for the arrangement 

 of a strictly stratigraphical collection. 



In the description of the Cornish specimens much 

 valuable assistance was derived from a MS. left by the 

 late Sir Henry de la Beche. 



The arrangement of the rocks described in this 

 catalogue was planned, partly executed, and the whole 

 superintended by myself. A very large part is the 

 work of Mr. Bristow. The case of Yesuvian specimens 

 was arranged by Mr. Bauerman, who also assisted in 

 cataloguing the igneous rocks of Wales. 



ANDREW C. RAMSAY. 



Museum of Practical Geology, 



Nov. 2, 1857. 



