Reviews 



Report on the Buildi?ig and Decorative Sto?ies of Maryland. By 

 George P. Merrill and Edward B. Mathews. Part II, 

 Vol. II, Geol. Survey of Maryland. 



The first 75 pages of the Building Stone Report of the Maryland 

 Geological Survey are written by George P. Merrill, and comprise a 

 discussion of the physical, chemical, and economic properties of build- 

 ing stones. The following 116 pages are written by Edward B. Mathews, 

 and are an account of the character and distribution of Maryland build- 

 ing stone. 



In the first part Merrill classifies the rocks of Maryland, which are 

 available for constructive and ornamental purposes, into (1) granites 

 and gneisses; (2) common limestones and dolomites; (3) the marbles 

 (crystalline limestones and dolomites); (4) sandstones and conglomer- 

 ates; and (5) the argyllites and slates. The three great classes of 

 rocks, eruptive, clastic sedimentary, and metamorphic ; the diversity 

 of the geological resources of Maryland; the method of formation, 

 present position, and the conditions under which the sedimentary and 

 igneous rocks formed ; and the way in which mountain-building 

 forces have since modified them, are successively discussed. 



The author explains how several grades, and often kinds, of sedi- 

 mentary rocks may occur in a single quarry. The effect which the 

 position of the strata, horizontal or tilted, has upon the cost of quar- 

 rying ; the size and shape of the blocks resulting from jointing and 

 bedding ; the manner in which river erosion, weathering, and glaciers 

 influence the accessibility of the stone in the quarry ; and the mis- 

 leading nature of dry seams and superficial induration, are clearly 

 explained. 



Following a discussion of the general distribution of Maryland 

 building stones in reference to the physiographic regions of the state, 

 Merrill considers the methods of quarrying and the more important 

 kinds of machinery now employed. The important part which com- 

 petition plays in the development of the stone industry has led to a 



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