144 MECHANICAL CONDITION OF ROCKS. 



close proximity of a granitic district on our right cuts 

 them off abruptly, and has probably changed very much 

 their physical and mechanical characters. 



Nothing more clearly shows the importance of the 

 physical and mechanical characters of a rock on the 

 kind of soils it is capable of producing, than the different 

 aspect and capability of two adjoining districts, over 

 which the rocks are the same in kind and in general 

 chemical composition, but in one of which they occur, 

 if stratified, in their natural unchanged condition, in the 

 other in what is called a metarn orpine or hardened 

 state a condition they have been made to assume by 

 the agency of heat. Tracts of rich wheat and hard 

 wood land may extend in the former district, alongside 

 of poor, stony, inhospitable stunted pine-lands on the 

 latter. A knowledge of the ultimate chemical composi 

 tion of its rocks or soils is not of greater importance, in 

 reality, than that of the mechanical condition of the 

 rocks of a country, or of the fragments that form its soils. 



Cedar-swamps, alternating with naked rocky hills and 

 rarer banks and slopes of better soil, accompanied us to 

 Macgowan s, half-way to St Andrews, when dark night 

 overtook us. We were still, however, five miles from 

 Macadavic, where we were to quarter for the night, 

 when daylight forsook us, and upon the low black 

 swamps, with dark pine-forests closing us in on either 

 side, we very soon began to find it dinicult to pick our 

 way. While the country was level, we crawled along 

 without much apprehension ; but on approaching a long 

 steep descent with a ravine on the right, we were happy 

 to avail ourselves of the pilotage of a native, whom we 

 picked up at a house on the wayside. The darkness 

 was as impenetrable as a London fog, with the additional 

 discomfort of intense blackness ; but two hours of 

 alternate walking and driving brought us in safety 

 through the Pennfield Settlement, which we could not 



