GYPSUM QUARRIES 75 



worked by steam. His gypsum sells for $3 per ton to phos- 

 phate companies and $4 per ton to the retail trade. 



At Port Gibson, which is about 4 miles from Mr Miller's 

 quarry and mill at Phelps, and to the north on the border 

 between Ontario and Wayne Cos., Mr Ezra Grinnell has a 

 quarry of plaster and a mill worked by water. Mr Grinnell 

 has not worked any this year. The characteristic of this 

 rock is that it is disseminated with crystals of gypsum or 

 " isinglass " as it is locally called. The plaster is found in 

 the bed of a stream near Mr Grinnell's residence. The 

 greatest thickness he has worked is 18 ft. The stream is 

 diverted for the use of a mill leaving the bed in condition, 

 to work with some pumping. Large blasts are put in and 

 a large amount of rock is loosened at a blast. 



The next locality west where plaster is quarried is in 

 Garbuttsville in Monroe Co. where Mr Samuel W. Weeks 

 and Mr J. W. Garbutt are operating. The quarries here are 

 all underground, and the product is known commercially as 

 Caledonia White Land Plaster. Mr Weeks is at present 

 operating only one pit but two have been worked this year. 

 The pit now working was dug last spring and the shaft is 

 53 ft. deep. The thickness of the plaster rock varies be- 

 tween 4 and 8 ft. averaging perhaps 6 or 7 ft. The material 

 is a gray plaster. Mr Weeks does a business of about 2000 

 tons per year. FF black powder is used for blasting and 

 wheelbarrows are used for handling the product under- 

 ground. The rock above the plaster is a kind of water lime 

 and the rock under is a lime stone. A few feet below a 

 second plaster bed is known to exist. These beds are known 

 in places but they are run out in places to two, one or none. 

 Short drills are used. The product is drawn to the mill in 

 wagons. The gypsum is harder towards the bottom layer 

 and is sometimes difficult to loosen from the associated rock. 

 The bottom layer of gypsum or " hard plaster" will average 

 from 18 ft. to 20 ft., then comes a bed from 14 ft. to 18 ft. 

 thick, both of these are more or less whitish in appearance. 



