104 Things not generally Known. 



ffieologg antr 



IDENTITY OF ASTKONOMY AND GEOLOGY. 



WHILE the Astronomer is studying the form and condition and 

 structure of the planets, in so far as the eye and the telescope 

 can aid him, the Geologist is investigating the form and con- 

 dition and structure of the planet to which he belongs ; and it 

 is from the analogy of the earth's structure, as thus ascertained, 

 that the astronomer is enabled to form any rational conjecture 

 respecting the nature and constitution of the other planetary bo- 

 dies. Astronomy and Geology, therefore, constitute the same 

 science the science of material or inorganic nature. 



When the astronomer first surveys the concavity of the ce- 

 lestial vault, he finds it studded with luminous bodies differing 

 in magnitude and lustre, some moving to the east and others 

 to the west ; while by far the greater number seem fixed in 

 space ; and it is the business of astronomers to assign to each 

 of them its proper place and sphere, to determine their true 

 distance from the earth, and to arrange them in systems 

 throughout the regions of sidereal space. 



In like manner, when the geologist surveys the convexity of 

 his own globe, he finds its solid covering composed of rocks 

 and beds of all shapes and kinds, lying at every possible angle, 

 occupying every possible position, and all of them, generally 

 speaking, at the same distance from the earth's centre. Every 

 where we see what was deep brought into visible relation with 

 what was superficial what is old with what is new what 

 preceded life with what followed it. 



Thus displayed on the surface of his globe, it becomes the 

 business of the geologist to ascertain how these rocks came 

 into their present places, to determine their different ages, 

 and to fix the positions which they originally occupied, and 

 consequently their different distances from the centre or the 

 circumference of the earth. Raised from their original bed, 

 the geologist must study the internal forces by which they 

 were upheaved, and the agencies by which they were indurated; 

 and when he finds that strata of every kind, from the primitive 

 granite to the recent tertiary marine mud, have been thus 

 brought within his reach, and prepared for his analysis, he 

 reads their respective ages in the organic remains which they 

 entomb ; he studies the Banner iu which they have perished, 



