126 Dr Lauder Lindsay on the Place and Power of 
such an infallible, or at all events comparatively accurate, index ; 
for the mere mineral characters are often utterly insufficient. For 
instance, there is a red sandstone above and another below the 
Coal Measures, the one called the New Red and the other the Old 
Red Sandstone, in reference to their comparative ages,—alike in 
regard to mineral characters, that 1s as to colour, composition, 
and texture. The novice cannot tell the one from the other; but 
the paleeontologist—the expert who is conversant with the fossils 
which characterise the earth’s strata—can at once say which 
is which, Knowing that the geological position of the Coal 
Measures is between these two series of rocks, the man of science 
would never be so stupid, nor so rash, as to be at the trouble and 
expense of sinking coal-pits through the Old Red Sandstone in the 
hope of finding coal; while he would do so through the New Red 
with every probability of success. But, look at the position of 
the landowner or coal speculator ignorant of these elementary 
facts in geology. He may ruin himself by sinking shafts through 
the Old Red Sandstone, for a mineral which cannot be found below 
it; or he may lose a fortune should he mistake the New Red for 
the Old Red Sandstone, by refraining from digging where coal may 
with every probability be found. This is no hypothetical case ; 
I have known landowners ruining and stultifying themselves by 
boring or sinking shafts for coal through the Old Red Sandstone 
on the Perthshire base of the Ochils in Scotland. I have already 
quoted the familiar adage—“ All is not gold that glitters.” Neither, 
may it be equally truly added, is every rock that is black coal! 
There is no lack of black rocks in the earth’s crust; many shales 
are sufficiently black and carbonaceous: they contain more or less 
vegetable matter, yet are they not coal, nor do they belong to the 
Carboniferous system. ‘The Silurian slates, for example, are fre- 
quently very black and carbonaceous, quite as much so as many 
shales of the true coal measures; they are so where I have ex- 
amined them in the neighbourhood of Dumfries. Now the Silurian 
system is inferior in the geological scale to the Old Red Sandstone ; 
and if no coal is to be found below the latter, still less will it be 
found belowthe former. Led astray, however, by the coal-like aspect 
of such shales—having confidence in their own judgment and cun- ~ 
ning, ignorant altogether of geology, too parsimonious to spend a 
few guineas on a survey and report from a mining geologist—I 
have heard of Dumfriesshire lairds ruining themselves by expensive 
borings through these same Silurian slates. The late Mr Rose, con- 
sulting geologist, Edinburgh, I have heard tell many stories of the 
same kind; sufficiently numerous instances occur, indeed, in the 
experience of all practical geologists.* Such cases, indeed, are the 
* Let me here cite the testimony of what is at once the most recent and 
(according to the “ Edinburgh New Philosophical Journal” for Oct. 1862, p. 
