424 CRITICAL NOTICES OF NEW PUBLICATIONS. 



glomerate measures, have generally a contrary inclination. This chapter 

 comprises facts indicative of the author's intense and varied observation. 



Chap. VII. — Here, we have an exhibition of the facts which prove, 

 that faults are the result of a general law, rather than of earthquakes ; 

 and, according to our author's views, this is induration, the processes of 

 which are quiet, uniform, and natural. He reasons thus on p. 59 : ** if 

 it should be found that the slips or faults in coal-strata, in limestone 

 rocks, in sandstone, slate, and almost all rocks, are universally of the 

 same nature ; and, if proper allowance be made for the composition of 

 the substances, for its declination as to the bed, and for its other local 

 relations, must not the origin of faults be referred to some general law 

 of nature? Cannot induration alone account for it? Volcanos and 

 earthquakes are not proved to be so uniform in their action as to produce 

 the effect. If the process of desiccation, compression, and induration, 

 be strictly investigated, in its natural bearings, its results will explain 

 the phenomena of faults, throughout the Ashby coal-field, in all their 

 modifications." Hypothetical geognosophists might derive some avail- 

 able instruction from a careful study of these propositions and their 

 applications. 



Chap. VIII. — Coal seams preserve their thickness, quality, indicative 

 characters, and relative distances, to a surprising extent in this field ; 

 and the evidences which confirm this position are numerous and certain. 

 Mr. M. has selected two seams for a detailed description ; because, he 

 says, they may be readily recognised in any part of the field hitherto 

 proved : these are — the seam called the main coal, and that named the 

 five-feet coal, lying seventy yards above the former ; and the characters 

 he ascribes to each of them have been proved by the workings extending 

 over eight or ten square miles, from the southern, eastern, and western 

 bassetings of the measures to the depth of one thousand feet on the 

 northern side. The arrangement of the beds of these two seams, par- 

 ticularly that of the main coal, is so uniform as to shew it, Mr. M. 

 thinks, to be the result of some fixed law operating during a quiescent 

 state of the original mass. 



Chap. IX. — This consists of observations *'on the fossils and their 

 use in mining ;*' and these observations merit the most profound atten- 

 tion : we make a long extract. ** Fossils in this coal-field may be 

 regarded," says Mr. M. at p. 64, "with very few exceptions, as apper- 

 taining to the vegetable world ; but, whether they can all be considered 

 as the production of land or fresh- water plants, remains to be proved. 

 Two shafts are each more than one thousand feet deep, and abound 

 throughout almost every stratum, with vegetable fossils : a few beds 

 only contain small shells, myce ovalis, and these are confined to a 

 layer of about two inches in thickness. In general, the shells are filled 

 with the bituminous shale in which they are imbedded ; occasionally 

 they are broken or crushed together ; but, for the most part, they 

 seem to have been filled under slight pressure and thus consolidated. 

 The study of these fossils is as interesting, in a geological view, as it is 

 important for practical purposes. The fossils depicted in the accom- 

 panying plates, appear to belong to vegetable classes produced in a 

 climate much hotter than that of England; and, in character, they 

 greatly resemble plants now found within the tropics. Two self-evident 

 propositions result from observation of their structure and abundance. 

 first, that their period must have been very remote, and vast denudations 

 have since taken place, by which the overlying masses known to be 

 formations over the coal, now border the coal-district. Secondly, that 

 the present theories, so laboriously constructed, are totally inadequate 



