28 HISTORY OF GEOLOGY AND PAL/EONTOLOGY. 



which accomplished the separation of light from darkness, or, 

 as he also expressed it, the separation of the more active 

 elements of the universe from the more passive. A further dif- 

 ferentiation of the inactive elements, according to their stability 

 and degree of resistance, determined the dry land and the 

 oceans. The escape of heated material from the interior of 

 the earth produced slaggy spots on the earth's surface, and as 

 these increased a glassy crust was formed. Thus the earth 

 was gradually converted from the condition of a radiant sun 

 to a dark planet. The cosmical theories of Leibnitz suffered 

 in the original from a want of clearness in the diction, and are 

 strained on account of the author's conscientious effort to pre- 

 sent a historical account of the earth's surface that should be 

 in harmony with the Mosaic genesis. 



That part of the Protogcea which deals with mineralogy is 

 much more practical. His official position at the Court of 

 Hanover enabled Leibnitz to become acquainted with the 

 mines and the natural products of the Harz mountains, and he 

 gave an account of the mode of occurrence of the metals and 

 minerals. He also supplied a detailed description, with illus- 

 trations, of a number of fossils occurring in Hanover and 

 Brunswick in the copper schists. 



If Leibnitz was careful to make his theory of the earth con- 

 form with the Mosaic account of Creation, this feeling was far 

 more strongly expressed in England. 



Dr. Thomas Burnet, in his Sacred Theory of the Earth, pub- 



(lished 1 68 1, thinks that in the beginning our earth was a 

 chaotic mixture of earth, water, oil, and air, which gradually 

 consolidated into a spherical form. The various rock-ingre- 

 dients separated out from the primitive chaos according to 

 their weight, the heaviest "material accumulating round the 

 earth's centre; this in its turn was surrounded by water, on 

 whose surface the oily material floated, and the atmosphere 

 enveloped the whole. Gradually, the finer particles that had 

 been held in suspension in the atmosphere settled upon the 

 oil and formed a fatty superficial layer that afforded nourish- 

 ment for the first plants, animals, and human beings. 

 \ The earth was oval, and its axis stood upright, in the same 

 Iplane as the earth's path, hence there were no alternating 

 Reasons, no mountains, no seas, no rivers, no storms. It 

 'rained only at the poles, but the water filtered at once into the 

 earth's interior. This state of earthly paradise lasted 1600 



