208 NATURAL SCIENCE [September 



The Skeleton of Maryland 



Maryland Geological Survey. Volume One. By "Win. Bullock Clark, State 

 Geologist, E. B. Matthews, and L. A. Bauer. 8vo, 540 pp. and 17 plates. 



With its first volume of Eeports, the Geological Survey of Maryland 

 makes an imposing, attractive, and generally successful start. This 

 Survey has the benefit, inestimable in America, of being removed 

 from the immediate control of politicians, since it is under the direc- 

 tion of a commission " composed of the Governor, the Comptroller, the 

 President of the Johns Hopkins University, and the President of the 

 Maryland Agricultural College." We may therefore expect the ful- 

 filment of the promise that other volumes will follow, dealing with 

 the mining, geology, palaeontology, mineralogy, forestry, agricultural 

 physics, and so forth. 



The present volume opens with an Introduction by Professor 

 Clark, who relates the history of the establishment of the Survey, 

 describes its plan of operations, and then gives an account of the pro- 

 gress of investigation concerning the physical features and natural 

 resources of Maryland. This is followed by an outline of present 

 knowledge of the physical features of the State, embracing an account 

 of the physiography, geology, and mineral resources. This also is 

 from the pen of Mr Clark ; it occupies 87 pages, and is illustrated by 

 a hypsometric and a geological map and several photographic plates 

 of scenery. A useful appendix to this is a bibliography and carto- 

 graphy of Maryland, with special reference to its geology, by Dr E. B. 

 Matthews, who was assisted in the compilation by all the members 

 of the Survey. The volume concludes with the First Report upon 

 Magnetic work in Maryland, by Dr L. A. Bauer, who has been con- 

 ducting this division of the work of the Survey. 



The State of Maryland forms part of the eastern border region 

 which stretches from the Atlantic coast to the crest of the Alle- 

 ghanies, and from its central situation affords, perhaps, the most 

 characteristic section of this broad belt. In Maryland, as elsewhere, 

 this part of the continent is divided into three physiographic areas : 

 the Coastal Plain, the Piedmont Plateau, and the Appalachian Eegion. 

 The Coastal Plain includes rather over one half the land area of the 

 State (nearly 5000 square miles), and attains in places a width of 100 

 miles. By the great Chesapeake Bay, running north and south, it is 

 divided into the very low-lying Eastern Maryland, and a higher 

 western trait usually called Southern Maryland. The Piedmont 

 Plateau occupies somewhat over one quarter of the land area of 

 the State, being about 65 miles wide in the north, and gradually 

 narrowing to 40 miles in the south. It is divided by Parr's Ridge 

 into an eastern and western division. The former has a diversified 

 topography due to varied crystalline rocks with complicated structure ; 

 in it are broad, fertile limestone valleys running in various directions. 

 The western division includes the broad limestone valley of the Mono- 

 cacy, on which is the town of Frederick, and near the mouth of which 

 is Sugarloaf Mountain rising rapidly to a height of 1250 feet. The 

 Appalachian Region extends from the Piedmont Plateau to the 

 western limits of the State ; it comprises about 2000 square miles, and 

 attains a maximum width of 115 miles in the northern part of Mary- 



