Clapp, Frederick G.  1879-1944. <br/><br/>
Economic geology of the Amity quadrangle, eastern Washington County, Pennsylvania / 
by Frederick G. Clapp. 
 - Washington,  Govt. Print. Off.,  1907. 
 - 145, vi p. :  ill., viii pl. (partly fold., incl. maps) diagrs. ;  24 cm. 
 - U.S. Geological survey. Buletin  no. 300 .
 - Geological Survey (U.S.).  Bulletin ;  no. 300. .
<br/><br/> Subject series: A, Economic geology, 86; B, Descriptive geology, 105.  Issued also as House doc. no. 53, 59th Cong., 2d sess.  Includes index. 
<br/><br/>Bibliography: p. 140. 
<br/><br/><label>LCCN: </label>gs 07000794  
<br/><br/><label>Subjects--Topical Terms: </label><br/>Mines and mineral resources--Pennsylvania--Washington County.<br/>Geology--Pennsylvania--Washington County.
<br/><br/><label>LC Class. No.: </label>QE75  / .B9 no. 300