GARFOETH: FIRE-DAMP DETECTOR. 
403 
reduce the cause of sudden outbursts to a minimum ; at the same 
time prevent accumulations of gas, and form good roadways without 
leakage for the ventilation. 
An eminent writer asks, " May it not be said that the experi- 
ments of science are the answers made by nature, to the questions 
put to her by man." This remark ma^' for many reasons be con- 
sidered specially applicable to mining. If the laws of nature are 
scientifically and properly studied, it will be found that the difficulties 
of deep mining are far less than at present apprehended ; and though 
we may for a time be perplexed, yet in the long run it will be proved 
in mining, as in other things, that the fault does not rest with nature, 
whose wonderful laws appear grander and more marvellous the 
better they are understood. 
ON A NEW SPECIES OF HETEROLEPIDOTUS FROM THE LIAS. 
BY JAMES W. DAVIS, F.G.S., &C. (PLATE XXIl). 
Genus Heterolepidotus, Egerton. 
Head large ; snout obstusely conical ; maxillary and mandibular 
bones straight ; teeth of various sizes, the larger ones strong and 
bluntly pointed ; the smaller ones sharp and numerous ; gape wide ; 
pectoral and ventral fins large ; dorsal fin remote ; scales large, 
thick, and lustrous, more or less serrated on the posterior margins ; 
abdominal scales small and elongated; tail broad, the upper lobe 
ridged with strong fulcral scales. {Egerton.) 
Heterolepidotus minor, Davis. 
The specimen which forms the subject of the following 
description has been in my cabinet for some years awaiting the 
discovery of others which would exhibit more perfectly the characters 
lacking in this one. The body of the fish represented by the 
accompanying plate is slightly distorted so that the abdominal region 
is brought prominently forward, and both the right and left pectoral 
and ventral fins are exhibited in a more or less perfect condition. 
The scales are displaced ; the head is imperfect ; the whole of the 
