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GEOLOGY. 



his labours by forming a theory, which he afterwards 

 endeavoured to support by twisting nature to agree 

 with his own preconceived views of the organisation 

 of the earth thus beginning where he should have 

 ended. Now, however, a better directed philosophy 

 teaches us first to investigate the laws of nature and 

 attend to her phenomena ; and then, and not till 

 then, seek to combine the facts which actually pre- 

 sent themselves into one intelligible whole. So that 

 we first interrogate nature by the light of science, 

 and then from the answers that are obtained, we 

 conclude what must have been the probable chain 

 of events which led to the complete formation of the 

 vast system of wonders that we now behold. 



Foreign travel, and an intimate acquaintance with 

 every part of the globe, is commonly considered ne- 

 cessary for the progress of the geological student ; 

 such, however, is not the fact, as our own island will 

 furnish all that is necessary for illustrating the funda- 

 mental parts of this science. Within a few days' 

 journey of the metropolis may be seen vast temples 

 reared by the hand of nature, and admirably fitted 

 for illustrating some of her geological mysteries, 

 which far excel all the dreams of Arabian fiction. 

 One of these extraordinary natural structures has 

 already been described in the article BASALT, where 

 our readers will also find a description of the gigantic 

 causeway, which is supposed at one period to have 

 united Britain to the sister kingdom. But the geo- 

 logical wonders which may be thus traced rising from 

 the bed of the ocean, are equalled, if not surpassed, 

 by the submerged forests that are still traced with 

 their earth-bound vestments in the very heart of our 

 island, and where successive kingdoms of ocean and 

 dry land have been depositing their varied produce 

 of inhabitants for countless ages. Traces of animals 

 and vegetables that are now the exclusive property 

 of another hemisphere, are frequently laid bare in 

 every part of Great Britain ; and many that have left 

 no other records of their existence, save those that 

 the labours of the geologist have brought to light. 

 We may take the formation of coal as an example of 

 the extraordinary changes that have gone on in the 

 immediate neighbourhood of the earth's surface. The 

 black, glossy, and compact mass which we call coal, 

 is now pretty generally admitted to be of vegetable 

 origin. It is altogether unlike wood in its general 

 character, and yet, from the abundance of vegetable 

 bodies with which it is associated in some districts, 

 and the gradual transition that is occasionally found 

 between bodies perfectly analogous in their character, 

 there can be but little doubt of the fact. One school 

 of geologists supposing it to be formed by the power 

 of heat, acting on vegetable bodies under great pres- 

 sure : and another supposing it to be produced by 

 the mere effects of time and chemical change. But 

 we must now examine somewhat in detail the various 

 hypotheses that have been offered by the most emi- 

 nent writers for explaining and illustrating the struc- 

 ture of the earth. 



The first theory of geology which deserves to be 

 noticed is that of the Rev. Dr. Thomas Burnet. 

 This celebrated author was a man of considerable 

 genius, and his work, entitled Tellurius Theoria Sacra, 

 though it cannot command the assent of the philoso- 

 phic mind, will be found to display much learning 

 and a very romantic imagination. According to 

 Dr. Burnet, the earth was first a fluid heterogeneous 

 mass. The heaviest parts descended and formed a 



solid body. The waters took their station round this 

 body, and all lighter fluids rose above the water. 

 Thus, between the coat of the air and that of the 

 water, a coat of oily matter was interposed. But as 

 the air was then full of impurities, and contained 

 great quantities of earthy particles, these gradually 

 subsided and rested upon the stratum of oil, and 

 composed a crust of earth mixed with oleaginous 

 matter. This crust was the first habitable part of the 

 world, and was level and uniform, without mountains, 

 seas, or other inequalities. In this state it remained 

 about sixteen centuries, when the heat of the sun, 

 gradually drying the crust, produced at first super- 

 ficial fissures or cracks ; but, in process of time, these 

 fissures became deeper, and increased so much that 

 at last they entirely penetrated the crust. Immedi- 

 ately the whole split in pieces, and fell into the abyss 

 of waters which it had formerly enveloped. This 

 wonderful event, according to Dr. Burnet, was the 

 universal deluge. These masses of indurated earthy 

 matter, in falling into the abyss, carried along with 

 them vast quantities of air, by the force of which 

 they dashed against each other, accumulated, and 

 divided in so irregular a manner, that great cavities, 

 filled with air, were left between them. The waters 

 gradually opened passages into these cavities, and in 

 proportion as the cavities were filled with water, 

 parts of the crust began to discover themselves in 

 the most elevated places. At last the waters ap- 

 peared nowhere but in those extensive valleys which 

 contained the ocean. Thus, according to this theory, 

 our ocean is a part of the ancient abyss, and the rest 

 of it remains in the internal cavities, with which the 

 sea has still a communication. Islands and rocks 

 are the small fragments, and continents the large 

 masses, of the antediluvian crust ; and as the rupture 

 and fall of the mass was sudden and confused, the 

 present surface of the earth is full of corresponding 

 confusion and irregularity. 



The following passage from Burnet's work has 

 been highly eulogised by Steele, and certainly it 

 merits praise ; it is a funeral oration over the globe : 

 " Let us now," says he, " reflect on the transient 

 glory of the earth ; how, by the force of one element 

 breaking loose on the rest, all the beauties of nature, 

 each work of art, and every labour of man, aro re- 

 duced to nothing ; all that once seemed admirable is 

 now obliterated ; all that was great and magnificent 

 has vanished ; and another form and face of things, 

 plain, simple, and uniform, overspreads the earth. 

 Where are now the empires of the world ? where the 

 imperial cities, the pillars, trophies, and monuments 

 of glory ? what remains, what impressions or distinc- 

 tions do you now behold ? what is become of Rome, 

 the great city ; of eternal Rome, the empress of the 

 world, whose foundations were so deep, whose palaces 

 were so sumptuous ? her hour is come ; she is wiped 

 from the face of the earth, and buried in everlasting 

 oblivion. But not the cities only, and the works of 

 men's hands, but the hills and mountains and rocks 

 of the earth are melted as wax before the sun, and 

 their place is nowhere found ; all have vanished and 

 dropped away, like the snow that rested on their 

 summits." 



The " elegant romance " of Burnet was succeeded 

 by the work of his countryman, Mr. Woodward, who 

 in 1695 published " Essays towards a Natural History 

 of the Earth, and Terrestrial Bodies." Though he 

 possessed a much better acquaintance with minerals 



