Reviews—Penning’s Field Geology. 177 
of measures above the Barnsley Coal, though many are sunk to the 
Sukstone at places below the outcrop of the Barnsley. This results 
in a concentration of coal-pits towards the western margin of the 
coal-field, and the existence of a large area of unproved ground 
towards the escarpment of the Magnesian Limestone, which is the 
more difficult to make out in detail from a greater variability in the 
sandstones coinciding with this dearth of colliery information. Among 
the uppermost of the Coal-measure beds, the most interesting is the 
Red Rock of Rotherham, which the labours of the Geological Survey 
have shown to lie unconformably on the beds below it. And on the 
other hand its Carboniferous age is shown by the presence above it, 
on the Midland Railway a mile south of Masborough, of beds of the 
ordinary Coal-measure type. No igneous rocks are found anywhere 
in the Ooal-field. 
The third great chapter occupies 270 pages of the book, and is 
divided into 88 sections. It deals with the present position and lie 
of the rocks. The country is divided into districts, each of which is 
treated by itself. The boundaries of these districts are either natural 
features, such as river-valleys or great escarpments ; or geological 
lines, such as coal-crops or lines of fault. As in this chapter is 
given a detailed account of the geological and physical structure of 
the whole district, it is impossible to do more than simply mention it. 
Chapter the fourth is concerned with glacial and river deposits, 
and occupies only 25 pages. There is an appendix consisting of a 
list furnished by Mr. W. Whitaker, F.G.S., of the books, papers and 
maps relating to the geology of the Yorkshire Coal-field and its 
neighbourhood, arranged chronologically: also a good index, the 
work of Mr. W. H. Dalton. 
In conclusion, it must be remarked that it is a great pity that 
works such as the above should, from their advent not being suffi- 
ciently heralded by advertisements, and from neglect in sending 
copies for review, remain almost or quite unknown to many to whom 
they would be of the highest benefit. Government publications are 
no better protected than other literary productions from “ wasting 
their sweetness on the desert air,” in the absence of the proper 
means for making their existence known.—JZ, 
IL—A Text-Boox or Firtp Gronocy. By W. Henry Pennine, 
F.G.S. With a section on Paleontology, by A. J. Juxes- 
Brownz, B.A., F.G.S. Second Edition. 8vo. pp. 3819, 
Geological Map, and twenty-nine Woodcuts. (London: 
Balliére, Tindall, and Cox, 1879.) 
N the Gsonocican Maaazine for October, 1876, we called the 
attention of our readers to the “ Field Geology” by Myr. 
Penning, then just published. We have now much pleasure in 
noticing the second edition of the work, which, with nearly one 
hundred additional pages, has become a good-sized volume. The 
new matter. comprises further notes on the process of mapping, on 
levelling, and on the characters of the rocks to be observed in the 
DECADE II.—VOL, VII.—NO. IV. 12 
