520 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



of sand and gravel about 65 feet from the surface. This well was on 

 lower ground than the one south of it in section 7, which strikes rock at 

 less than half the depth. The rock surface in this neighborhood has a range 

 in altitude of not less than 90 feet, while the drift surface varies scarcely 

 40 feet. 



Wells along the pike east of Portland for about 4 miles strike rock at 

 45 or 50 feet. In some of these the upper portion of the drift is sand, in 

 others a j^ellow till. The blue till is entered at 15 to 30 feet. In ditching 

 or tile draining there are found to be abrupt changes from sand and gravel 

 to till. 



Borings for natural gas in the vicinity of Portland show considerable 

 variation in the altitude of the rock surface, and consequently of the thick- 

 ness of the drift, since the region is nearly plane. Notes concerning at least 

 20 borings were obtained, and in these the drift ranges from 40 to 160 feet 

 in thickness. About 2 miles southwest of Portland, in sec. 30, T. 23, E. 14 

 E., there are rock outcrops in the valley of the Salamonie River at a level 

 but 25 to 30 feet below that at the railway station at Portland. 



Near the sharp gravel knolls which constitute the strongly morainic 

 tract in western Jay County a well at Emery Gray's, in the NE. corner 

 of sec. 30, T. 24, R. 13 PI, penetrated the following strata: 



Section of Gray's well, near Camden^ Ind. 



Feet. 



Yellow till 18 



Blue till - 128 



Sand 9 



Total 155 



This well is just south of the valley in which the knolls lie, and is 

 apparently in the line of the deep buried channel which, as above noted, 

 Bownocker has traced from Rockford, Ohio, to Blackford County, Ind. A 

 well at Mr. Branson's, north of the valley, and so near as to overlook it, is 

 125 feet in depth and is almost entirely through till. A well overlooking 

 the water parting in the valley from the south side (in south part of sec. 19, 

 T. 24, R. 13 E.) penetrated 74 feet of till before entering assorted material. 



At Camden the first gas boring penetrated 41 feet of drift, as follows: 



Drift in gas horing at Camden, Ind. 



Feet. 



Bluish till. 18 



Gravel 22 



Clay 1-2 



