Reviews—Geological Survey of Pennsylvania. B75 
Ohio. By J.C. Wurre. With Geological Map and 134 Vertical 
Sections. 
3. Second Report of the Progress of the Laboratory at Harrisburg. 
By A. 8. McCreatu. (Harrisburg, 1879.) 
4, Atlas to the Coal Flora of Pennsylvania and of the Carboniferous 
Formation throughout the United States. By Lo Lusquereux. 
Eighty-seven Plates with Explanations. (Harrisburg, 1879.) 
5. The Permian or Upper Carboniferous Flora; or West Virginia 
and 8.W. Pennsylvania. By W. M. Fonratnn, M.A., and J. C. 
Wurrr, A.M. With thirty-eight Plates. (Harrisburg, 1880.) 
ee volumes form a continuation of a series of reports and 
papers (now about thirty in number) published by the Board 
of Commissioners of the Second Geological Survey of Pennsylvania, 
under the direction of J. P. Lesley (State Geologist) and an efficient 
staff of assistant geologists. 
No. 1. This volume contains the results of certain special geolo- 
gical surveys made by Mr. Chance while acting as assistant to Mr. 
Carll, in the Baltic County Oil Region in 1876, and also of the more 
systematic survey of the fifteen northern townships which he after- 
wards made in 1878. The first six chapters are devoted to the 
general geology of the district, which chiefly consists! of the 
Carboniferous Series, including the Lower Barren-measures, and the 
Lower Productive Coal-measures, and the Beaver River or Conglome- 
rate Series; the surface features being modified by anticlinal and 
synclinal folds as well as by the effects of pre-glacial and glacial 
action. Chapters 6—10 give the detailed geology of the different 
townships, and of the Oil-fields of Butler County. 
No. 2. In this report Prof. White describes the geology of 
‘Lawrence County, the rocks of which belong exclusively to the 
Coal-measure and sub-Carboniferous formations, of which detailed 
descriptions are given in chapters 2 and 35. The surface features 
have been moulded by glacial action, but unlike Butler County there 
is an absence of folds, for the forces which uplifted the strata to the 
south-east along the Alleghanies seem to have expended their 
activity before reaching Lawrence. Prof. White attributes the 
marked difference in the contour of the northern and southern halves 
of the county with the distribution of the drift. During the Glacial’ 
epoch the ice-sheet moved southwards, ploughing down all the 
northern part pretty much to the same level, forming wide level 
areas on the summits of the hills, while south of the glacial area 
no such planing down of the pre-glacial hills took place, and thus 
this part of the county is much more broken and rugged than the 
Northern. 
Appended is a special report on the correlation of the Coal-, 
measures of Western Pennsylvania and Eastern Ohio. ‘This and the 
preceding report are illustrated with geological maps and numerous 
vertical sections, and are supplemented with a series of indexes 
giving an exhaustive summary of the contents of the reports. 
No. 8. The Laboratory report, by Mr. A. 8. McCreath, contains a 
series of analyses classified to some extent both geologically as well 
