30 NEW YORK STATE MUSEUM 



very gradually as a rule. The volume of ore contained by a given 

 area can thus be ascertained with reasonable accuracy from observa- 

 tions taken at wide intervals, even of several miles under favorable 

 circumstances. 



The present exploratory work was performed entirely with a 

 diamond core drill. By this means a core, i inch in diameter, rep- 

 resenting a section of the rocks and ore penetrated was secured. 

 The cost of drilling has been somewhat greater than if the holes had 

 been put down without attempting to obtain a core, but the increased 

 expense may be considered to be counterbalanced by greater accu- 

 racy and detail in the results.^ 



With the meager information to be had from outcrops, the drill 

 cores have served also to clear up many doubtful points regarding 

 Clinton stratigraphy. The succession of rocks has now been estab- 

 lished with satisfactory completeness throughout the belt. 



The holes to the number of 8 in all were put down between Wall- 

 ington, Wayne co., and Verona Station, Oneida co. The average 

 interval between successive holes may be stated at about lo miles. 

 Most of the sites were selected with a view to striking the ore at 

 depths between lOO and 200 feet, a convenient depth for the drill 

 as well as one that permits estimation of a large volume of the 

 deposits. Under normal conditions of dip and surface topography 

 the holes would be from i to 3 miles from the outcrop, and their 

 results can thus be accepted with a degree of safety as an average 

 for about twice that width across the dip. 



The detailed sections for each drill hole are shown in the tabula- 

 tions that follow. From their consideration, together with the facts 

 , hitherto ascertained, it has been possible to prepare a general survey 

 of the ore distribution throughout the belt. 



Wallington, Wayne co. The site of the drill hole is on the 

 farm of Isaac Du Bois about ^ mile west of the trolley station 

 at Wallington, on the west side of Salmon creek and approximately 

 5 rods north of the highway leading from Wallington to Sodus 

 village. The locality lies i^ miles north of the outcropping edge of 

 the Lockport dolomite, which is shown in the vicinity of Sodus 

 Center, and 2^ miles directly south of the site of the old Sodus iron 

 furnace on Salmon creek, near which the Clinton strata with a thiii 

 seam of ore are exposed. 



^ It may be mentioned that the diamond drill proved to be well adapted for the work. 

 Owing to the frequent alternations of hard and soft strata characteristic of the forma- 

 tion, It was thought some difficulty might be 'encountered in removing a core, but in 

 every case a nearly complete section was obtained. The occasional loss of a part 

 of the core due to grinding of the harder material in the " core barrel " entailed 

 no serious discrepancies in measurements, since a constant check was maintained by 

 observations of the lengths of the drill rods in use and the character of the rock 

 material washed up from below. 



