506 HISTORY OF GEOLOGY. 



Mineralogy or Botany : and will be found to exhibit some of the fea 

 tures of that class of sciences. 



Since, then, our History of Descriptive Geology is to include only 

 systematic and scientific descriptions of the earth or portions of it, we 

 pass over, at once, all the casual and insulated statements of facts, 

 though they may be geological facts, which occur in early writers ; 

 such, for instance, as the remark of Herodotus, 8 that there are shell? 

 in the mountains of Egypt ; or the general statements which Ovid put- 

 in the mouth of Pythagoras : 3 



Vidi ego quod fuerat solidissima tellus, 

 Esse fretum ; vidi factas ex sequore terras, 

 Et procul a pelago conchse jacuere marinte. 



We may remark here already how generally there are mingled with 

 descriptive notices of such geological facts, speculations concerning 

 their causes. Herodotus refers to the circumstance just quoted, for the 

 purpose of showing that Egypt was formerly a gulf of the sea ; and 

 the passage of the Roman poet is part of a series of exemplifications 

 which he gives of the philosophical tenet, that nothing perishes but 

 everything changes. It will be only by constant attention that we 

 shall be able to keep our provinces of geology distinct. 



Sect. 2. Early Descriptions and Collections of Fossils. 



IF we look, as we have proposed to do, for systematic and exact know- 

 ledge of geological facts, we find nothing which we can properly 

 adduce till we come to modern times. But when facts such as those 

 already mentioned, (that sea-shells and other marine objects are found 

 imbedded in rocks,) and other circumstances in the structure of the 

 earth, had attracted considerable attention, the exact examination, col- 

 lection, and record of these circumstances began to be attempted. 

 Among such steps in Descriptive Geology, we may notice descriptions 

 and pictures of fossils, descriptions of veins and mines, collections of 

 organic and inorganic fossils, maps of the mineral structure of coun- 

 tries, and finally, the discoveries concerning the superposition of strata, 

 the constancy of their organic contents, their correspondence in differ- 

 ent countries, and such great general relations of the materials and 

 features of the earth as have been discovered up to the present time. 



ii. 12. ' Met. xv. 262. 



