164 



at length man has been called into being, to fulfil his ap- 

 pointed time. " All is change ! all is variable ! save the 

 laws by which they are governed, and He who framed 

 them." 



The aqueous or stratified rocks are due to the action 

 of water, and we must not suppose that this action has 

 ceased to be ; fire and water are in action still, the rocks 

 continue to grow as of oldj, mountains are formed, 

 islands rise out of the sea, and in its turn the sea claims 

 possession of the land. The plutonic rocks formed 

 deep in the bowels of the earth, become crystalized and 

 cooled, and then by elastic force of internal heat forced 

 upwards. Granite rocks are likewise fused deep within 

 the earth, and are not forced upwards until they are 

 cooled. We are indebted to fire for basaltic rocks, our 

 greenstone, porphyry, and serpentine. 



The aqueous rocks are the particles washed by the 

 rain into the rivers and carried into the sea, thence to 

 become solid, and lo be raised by subterraneous forces 

 In the lower Silurean epoch occurs as fossil the Trilo- 

 bite, stone lily and extinct fish. In the uj^per Silurean 

 uidLiiy sea shells, corals, fish, and marine algce. At this 

 period the world was considered to have been of a 

 similar heat throughout its breadth. The northern 

 hemisphere was avast sea, yet land occurred in Noitb 

 America. Towards the close of this epoch earthquakes 

 and volcanoes were very active. 



In the old red sand-stone or Devonian epoch, fossils 

 again occur. A warm and tranquil atmosphere pre- 

 vailed throughout the world, and the land of thenorthern 

 hemisphere teemed with tropical vegitation, These 

 grand forests were eventually submerged, blending with 

 clay and sand consolidated to produce our coal. In the 

 magnesian limestone animal remains are found, above 

 occur the mountain limestone, and uppermost the new 

 red sand-stone, dispersed with salt and gypsum, &c. 



