268 Clara Gould Mark 



by Charles Briggs, Jr., in the First Annual Report of the Geolog- 

 ical Survey of Ohio, published in 1838. In the Second A7inual 

 Report, published later in the same year. Col, J. W. Foster de- 

 scribed exposures of the Mercer limestone in Muskingum and Lick- 

 ing counties. Neither Mr. Briggs nor Col. Foster gave any name 

 to the limestone, but referred to it merely as ''blue limestone." 



In the Report of Progress in 1869 published in 1870, Professor 

 E. B. Andrews described the occurrence of the Mercer limestone 

 in Muskingum, Licking, Perry and Hocking counties, but owing to 

 an unfortunate mistake in identification by one of his assistants, 

 he called it, with but one exception, the "Putnam Hill limestone." 

 This one exception is in the description of the section at Putnam 

 Hill where the limestone in the bed of the Muskingum is said to 

 be possibly the same as the Maxville (p. 84). In the Report of 

 Progress in 1870 published in 1871, Professor Andrews contin- 

 ued tracing the line of the Mercer limestone from Hocking County 

 through Vinton, Jackson and Scioto counties to the Ohio River, 

 still calling it the ''Putnam Hill limestone" though at times 

 referring to it as the "Blue limestone." In the same volume is 

 an account by Dr. Newberry of exposures of the Mercer limestone 

 and Coal No. 3 which underlies it, in various localities from 

 Coshocton County east to the Pennsylvania line. 



Professor Andrews in volume i of the Geological Survey of Ohio 

 (1873, p. 317) calls attention to the mistaken use of the name 

 "Putnam Hill" for the Mercer limestone, and gives the correct 

 stratigraphical position of the Maxville, Mercer, and Putnam 

 Hill limestones in Muskingum County. He does not give any 

 name to the Mercer limestone, but describes it as a limestone 

 intermediate in position between the Maxville and Putnam Hill. 

 In volume ii of the Geological Survey of Ohio, 1874, pp. 81-180, Dr. 

 Newberry refers to the Mercer limestone a number of times as the 

 "Zoar limestone," but does not give any detailed description of 

 it. Dr. Orton was the first to give a careful description of it under 

 this name (vol. iii, 1878, p. 891). In this account he saj's that 

 the "Zoar limestone" is the best marked stratum in the Lower 

 Coal Measures of the State, and that it may be followed from the 

 Pennsylvania line across Ohio to the Ohio River. In the Report 



