68 LOWER PENINSULA. 



At Ann Arbor the drill hole sunk in the Court-House Square 

 struck the black shales at a depth of 525 feet below the surface, 

 their thickness there being 85 feet. In the south part of Washtenaw 

 County, and in the northwestern corner of Monroe County, in well 

 borings, the black shales are found usually not more than about 

 100 feet below the surface. Frequently a stream of hydrocarbu- 

 retted gas escapes from the drill holes after the black shales have 

 been reached. 



On the farm of Mr. Kinear, on Saline River, near Milan Village, 

 a well was bored with an auger through 106 feet of drift deposits, 

 partly clay, partly gravel. When the auger came upon the black 

 shales, suddenly, with a sort of explosion, hydrocarburetted gas 

 escaped from the opening, carrying with it mud and water to a 

 height of 30 feet above the surface. I visited the spot three 

 weeks after, and found the gas still escaping in a continuous stream, 

 which, at the opening of an inch iron pipe, burned with a bright, 

 illuminating flame 8 inches high. On several other farms in the 

 vicinity, similar gas wells were accidentally found while boring for 

 water. 



