64 ROCHESTER ACADEMV OF SCIENCE. [Jan. II, 



we might expect indications of the Wolf creek conglomerate in the 

 samples from near 350'. But the drillings show a quartz sandstone 

 from 96' to 116' and possibly at 135', which is lithologically nearer 

 what would be expected for the Wolf creek conglomerate than the 

 lower sandstones. At 174' is a grayish-buff sandstone (?) and from 

 212' to 251' a mixture of shale and gray to greenish-gray sandstone (?), 

 then from 251' to 406' nearly bluish, argillaceous shale. 



2d. If the mouth of the well is 2300' A. T. and near the horizon 

 of the Olean conglomerate, and if the top of the Richburgh oil sand 

 was reached at 1415', or 1420' according to the last well, then the 

 distance from the base of the Olean conglomerate to the top of the 

 Richburgh oil sand is only about 1420' instead of 1729' as stated by 

 Ashburner, (') a difference of about 300.' Or, if Ashburner were cor- 

 rect as to the distance, then the bottom of this well would be about 

 300' above the top of the Richburgh oil sand. However, Mr. Hatch 

 is confident that the well reached the oil sand and wrote me October 

 16, 1891, as follows: '* I am certain that wells No. 90 and 91 are 

 through the Richburgh oil and gas level. The bottom of the well 

 No. 90 is 1499' ; below the regular gas sand nothing was found except 

 slate." 



3d. Data given by Professor Williams are both for and against 

 the opinion that wells No. 90 and 91 reached the horizon of the Rich- 

 burgh oil sand. Against it is the fact that fragments of fossils were 

 noted from the brownish-gray sandstone as low as 1382', which is stated 

 by Mr. Hatch to be the bottom of the gas sand, and good specimens 

 of fossils were sent from the gas sand of well No. 90. Professor 

 ^\'illiams stated that in the oil sand of Varney & Co. 's well No. 11 

 at Bolivar, "no traces of fossils were seen." And the Professor con- 

 cluded : "It is probable that this sandstone [Richburgh oil sand] 

 is represented at the surface farther north by the Portage sand- 

 stones at Portageville." (^) Also, when describing the outcrop at 

 Portageville, the Professor said : " The petroleum odor associated with 

 all these gray sandstones following the black shales of the Portage 

 group, gives strong reason for the opinion that they are the sandstones 

 which occur farther south, and there, covered by thick masses of over- 

 lying strata, contain the oils reached by drilling." ('') 



(i.) Trans. Am. Inst. Min. Eng., vol. xvi, pp. 928, 929. There is a slight discrepancy in 

 Ashburner's account of the Cranston Wells, Nos. i and 2, on lot 29, Genesee township, from 

 which this distance was obtained. On page 928 it is stated that the top of the Richburgh oil sand was 

 struck in well No. i at a depth of 1704' and in the table on p. 932 it is given as 1632', a difference of 

 72'. On p. 928 well No. 2 reached the Richburgh sand at 1709' and on p. 932 at 1655', a difference 

 of 54'. 



(2.) Bull. U. S. Geol. Surv., No. 41, p. 90. 



(3.) /iid., p. 52. 



