Bishop— Geology of Erie County. 



387 



Surface Gas. 



Small quantities of gas escape from crevices in the rocks in many places 

 within the county. The most abundant supply comes from the Portage rocks 

 in the horizon of the lowest sandstones along a line connecting roughly 

 Wales Centre, East Aurora, North Boston and North Collins, and extending 

 eight or ten miles southeasterly. The lower Portage shales also furnish 

 supplies from rock crevices and water wells, and the Hamilton and Marcellus 

 some from similar sources. 



A few of the points at which gas has been noticed are at Eighteen-Mile 

 creek, near the lake ; between Wales Centre and East Aurora, where the 

 town-line road crosses a brook; near Holland; in Cazenovia creek, between 

 East Aurora and Griffin's Mills ; on Pipe creek, near West Falls ; in many 

 places in the town of Boston ; in the ravine between Shirley and North 

 Collins and near Lawton's station. 



Gas Horizons. 



In the wells which have penetrated the Trenton limestone in Erie 

 county, no gas has been found. The Bradshaw well, No. 2, in Niagara 

 county, however, furnished a little in that rock. The Depew well, No. 2, 

 struck a paying streak of gas in the red shale, a little less than 1,700 feet 

 below the top of the Corniferons limestone. Nearly all the gas obtained 

 within the limits of Erie county comes from the "white Medina" sandstone, 

 although some is found in the higher "red Medina," and occasionally in the 

 Clinton. The gas obtained from these sources is comparatively free from 

 sulphur and makes excellent fuel and a fair illuminant. 



The upper part of the Niagara group furnishes a variable amount of gas 

 in nian\' of the wells throughout the held. The most characteristic con- 

 stituent of this gas is sulphuretted hydrogen (H 2 S), commonly known 

 as "sulphur gas." Water in contact with the gas dissolves out the H 2 S, 

 becoming " sulphur water." Hence sulphur gas and sulphur water may occur 

 either together or separately, and the presence of either in the same formation 

 may determine the gas horizon. In ten wells it was found at depths varying 

 from 25 to 172 feet below the top of the Niagara, two having it at about 

 fifty feet and three at 130 feet. In six wells the average distance was 130 

 feet, which may be assumed as the horizon where we would be most likely to 

 find it. 



Wells No. 1, No. 2 and No. 3, at the Buffalo Cement Works, struck gas 

 at 450 to 460 feet, or about 400 to 410 feet below the Water-lime. Allowing 



