SECTIONS OF ARTESIAN WELLS. 529 



Section of well at Devils Lake. 



Feet. 



Gkicia] drift, till iis on tlie surface 25 



Dark shale, nearly alike tlirougli its whole thickness, including the Fort Fierre 



and Fort Benton formations, with no noticeable calcareous beds at the 



intermediate Niobrara horizon 1, 403 



Gravel, of granitic pebbles up to a lialf inch in diameter, firmly cemented with 



nodular pyrite 3 



Dakota sandstone, or rather a bed of loose sand, very tine, white, or light gray, 



the base of which was not reached .... 80 



Total 1,511 



From the sandstone, at the depth of 1,470 feet, brackish artesian 

 water came np with a rush, but sand soon filled the pipe so that the supply 

 became small. It is from this level that the present flow comes, through 

 narrow slits cut in 'the pipe. The boring was continued 40 feet deeper, 

 but no such strong flow was obtained below. In July, 1889, when the 

 well was completed, it supplied 1,800 barrels of water in twenty-four 

 hours, or about 40 gallons per minute, the diameter of the pipe being 8 

 inches, reduced to 3. J in the lower jiortion. The stream flowing away was 

 then turbid with the exceedingly fine particles of sand brought up from 

 the bottom. 



The Jamestown well, bored in the winter of 1886-87, about 8 feet 

 below the depot, or 1,400 feet above the sea, went tlnough a similar sec- 

 tion of about 1,400 feet of shales, with no distinctly difl"erent portion to 

 indicate the place of the Niobrara formation. 



At Deloraine, in Manitoba, 1,644 feet above the sea, situated close 

 northwest of the Turtle Mountain and about 100 miles northwest from the 

 city of Devils Lake, an unsuccessful boring for an artesian well has found, 

 under a thickness of 94 feet of ghicial drift, a somewhat uniform section of 

 shales, largely calcareous in their lower half, extending to the total depth 

 of 1,800 feet, according to Mr. J. B. Tyrrell, of the Geological Survey of 

 Canada.' At that depth, which was bored during the years 1888 to 1890, 

 the top of the Dakota sandstone liad not been reached, so that it is known 

 to be at least nearly 200 feet lower than at Devils Lake and more than 

 156 feet below the sea-level. 



' Trans., Roy. Soc. Canada, Vol. IX, Sec. IV, 1891, pp. 91-97. 

 MON XXV 34 



