CRITICAL NOTICES OF NEW PUBLICATIONS. 421 



Chap. I. — Mr. William Smith was the first to discover the principle — 

 that every stratum has its own peculiar fossil ; and, in this chapter, we 

 find Mr. M. pronouncing an honourable acknowledgment of its accuracy, 

 with the extent of its confirmation by his experience. Having well 

 considered the history of Mr. Smith's discovery, most thoroughly satis- 

 fied are we — that, as a scientific proposition, it constitutes a portion of 

 demonstrable truth. Wherefore, under this persuasion, we say further — 

 let it be tested generally, and, beyond all question, its applicability will 

 prove to be universal, and thus establish a pathetic claim upon the 

 legitimate patrons of science for the honour and rewards due to the 

 author of an inestimable improvement. 



Chap. II. — In this, Mr. M. explains the appearances which accompany 

 and indicate the evolution of carburetted hydrogen gas ; and, with his 

 usual perspicuity, he describes the processes by which its deleterious 

 influences may be contrasted or shunned. His communications on this 

 subject are particularly instructive. He admits the general usefulness 

 of the ** Davy-lamp," but has found that this valuable instrument is not 

 always a preventive of accidents ; and hence, by disappointments in 

 this way, he has been led to inquire whether some composition might 

 not be invented, by means of which the pressure of inflammable air 

 might be detected. This suggestion might become the source of vast 

 and diversified results, if it should be adopted and applied by those 

 chemical inquirers who make a study of the constitution and capa- 

 bilities of elementary agents. At p. 39, Mr. M. observes, "how far it 

 might be practicable to render this gas useful in mines, was perhaps 

 never thought of ; but the time may come when it will be made ap- 

 plicable to the general purposes of mining." He illustrates the feasibility 

 of this scheme by an experiment which was attended with complete 

 success. 



Chap. III. — This commences with an account of the quantity of water 

 in the Ashby mines, and a description of the processes by which it is 

 removed. Along with all this, are details of operations approved by 

 much practical experience, and here generously made available by 

 persons engaged in the management of similar works. These details 

 are succeeded by an analysis of the mineral waters used at the Ivanhoe 

 Baths of Ashby-de-la-Zouch ; then come a sketch of the appearances 

 of the saline water in the strata from which it issues, and an inquiry 

 concerning its origin and medicinal properties, with remarks on the 

 efilects attributed to the powerful agency of bromine. 



We condense Mr. M.'s details. " Generally/' he states on p. 36, the 

 saline water " makes its appearance in any adit in the coal, as soon as 

 driving commences : in some places it is more abundant than others ; 

 and, in a few, none of it appears. The coal is said to bleed; because, 

 for the most part, the water soon ceases to flow. This never spirts, nor 

 comes out with force, upon the pressure being removed ; but, it rather 

 oozes, and is accompanied with a gentle hissing noise, as if air were 

 escaping at the same time. It issues from small crevices, and seems to 

 be charged with inflammable air, which escapes as the water trickles 

 down. Sometimes, this air is so abundant that it may be fired ; and, 

 when ignited, it resembles a stream of burning alcohol. In driving an 

 adit in the solid coal, not so much as a drop of water is found at any 

 one point, and very little oozes from the roof or floor of the opening ; 

 but, what is very remarkable, on a lump of coal being detached, water 

 soon afterwards begins to be extilled from the crevices of the seam. 

 Immediately over the coal-measures from which the saline water exudes, 

 is a stratum of exceedingly fine fire-clay, about eighteen inches thick* 



NO. VI. 3 K 



