24 



INTRODUCTORY. 



Geologist that he no longer relies entirely on the Mineralogist 

 in the study of rocks,* but is able to determine the age and 

 position of any particular stratified rock by a careful examina- 

 tion of its fossils. Thus Mineralogy has of late become almost 

 a separate science, which treats of the chemical composition, 

 optical and other properties of rocks, minerals, metals and 

 precious stones ; whilst Geology investigates the origin, re- 

 lation, and distribution of the strata, — especially the sedimen - 

 tary formations, — the changes which our earth has undergone 

 in past times, as regards the distribution of land and sea, and 

 the vicissitudes of climate, evidenced by the old faunas and 

 floras of the globe which have successively lived, flourished, 

 and died on old land-surfaces, or in the lakes, rivers, and seas 

 of the past, the fossil remains of which fill the cases in our 

 Geological Galleries. 



Palaeontology has thus largely replaced Mineralogy as " the 

 handmaid of Geology y and, although the microscopic study of 

 rocks (in which the sister science Mineralogy comes to the aid 

 of the Geologist) has of late attracted a large share of atten- 

 tion and elicited much valuable information, yet, without 

 doubt, the investigation of the organic remains, which the 

 sedimentary rocks have revealed to us, will always prove more 

 attractive to the great majority of students. Just as the 

 Antiquary, who rescues some old mosaic pavement whose 

 myriad tessera have become ruptured and displaced by long 

 interment in the earth, strives to unite its precious fragments 

 and restore its pristine design for our admiration, so also the 

 Palaeontologist seeks from the fragmentary remains of a former 

 world to rehabilitate the old animals, and show us, by the aid 

 of comparative anatomy, what were the beings that once 

 peopled our earth in past ages before Man had left any record 

 of his existence. 



So many good books on Geology have been published that 

 it is not necessary to give in a Guide-book like the present 

 a treatise on the science, but merely to explain that the speci- 

 mens in the Geological Galleries are arranged according to 



* We must still depend on the Mineralogist and Chemist for the correct deter- 

 mination of the igneous and metamorphie rocks," in which no traces of fossil organ- 

 isms occur. 



