BUCKMAN — SEARCH FOR COAL. 



131 



same fact applies to the rock above, the roof of the coal. This, in 

 proper order, will be the Kew Red Sandstone ; and though this rock 

 may be absent, and newer deposits take its place, still the true coal 

 deposits are not found above the New E-ed Sandstone ; so that in 

 reality the table of strata, as now understood, represents rocks of dif- 

 ferent ages, each having its own established and relative position. 



Erom these considerations, then, it will be seen that it is often 

 easier to decide where coal is not than where it is — for as rocks of all 

 ages rise to the surface, or ''crop out," as the miner terms it, we may, 

 in such case, readily determine, even in a coal country, at least a limii; 

 to our search in one direction. 



W. Section 1. E. 



1. Siluriiin. 2. Old Red Sandstone. 3. Mountain Limestone. 4. Coal. 5. New Red Sandstone. 



6. Lias. 7. Oolites. 



Here we see that, as older beds crop out to the west, from beneath 

 the coal measures, it would be in vain to seek for coal in that direc- 

 tion ; so, in like manner, any well-done geological map of a district or 

 a country would give us distinct information on this point — for 

 wherever beds older than coal form the substratum it would be utter 

 folly to mine in them with the hope of finding coal. It was precisely 

 upon these principles that the geological surveyors of the state of 

 JS'ew York, I^'orth America, decided that this large State was without 

 coal, and thus put a stop to the wildest speculations, both theoretical 

 and practical, upon the subject, which had been the causes of so many 

 miserable failures. 



In our own country how many trials have been made for coal in 

 rocks older than that deposit? In that magnificent work, ''The 

 Silurian System," by Sir E,. I. Murchison, accounts are given of no 

 less than eight attempts to reach coal from Silurian rocks — sanguine 

 speculators being deceived by dark-coloured shales, a slight deposit of 

 carburet of iron, plumbago, or, as in one instance, a little real 

 anthracite. One of these is worth quoting : — 



*- Of coarse we are aware of coal deposits in tlie Oolitic and even in the Ter- 

 tiary rocks, but these are usually unproductive. 



