44 NEW YORK STATE MUSEUM 



hight. The rock is a light gray to brown gypsum with thin fibrous 

 gypsum veins running through it. The lower 2 feet are liarder and 

 od pooi'er quality. The mine has a good limestone roof, separated 

 from the gypsum by a thin parting of shaly rock known as rotten 

 roick. The second " bottom " or layer of gypsum is 12 to 15 feet 

 below the first and is separated from it by limestones. It appears 

 to be of a grade equail to the upper rock. The mining operations 

 have been conducted systematically, with pillars left every 21 feet. 

 The mine workings now extend about 2500 feet into the hill. Mine 

 no. I, or that nearest the trestle, is about worked out. The mines 

 are equipped with electric lights. Drilling is done with new auger 

 coal drills and blasting with low grade dynamite. The w:hole face 

 of gypsum is utilized, with noi sorting, but care is taken tO' sO' ar- 

 range the cars that the poor and good grades alternate at the mill. 

 At present tbe ore is hauled in steel cars b}^ mules tO' the scale 

 house, and then strings of cars are hauled across a wooden trestle 

 to the mill by a horse. At the time of our visit in August, tun- 

 nel no. 3 was being opened out at its mouth so as to permit of a 

 straight-away switch being laid, and tliey were preparing to in- 

 stal a system of electric haulage, to abandon mine no. i and haul 

 the product of nos. 2 and 3 out of no. 3. Aline no. 3 is 'less 

 troubled with water and contains tlie best quality of gy|:>sum. The 

 electric system will necessitate a new trestle over the creek to the 

 mill. Waste rock in the mine is utilized in banking up tbe sides 

 of the gangways and very little needs to be removed from the 

 mine. In mine no. i a shaft has been sunk through the lime- 

 stones to the lower layer, and enough of the gypsum removed 

 to prove that it is of good quality. By lowering the floor of the 

 no. I tunnel an incline could be built anrl the lower la3^er easily 

 worked. Some such plan is under consideration at present. After 

 crossing the trestle, the cars are drawn up an incline by oable to 

 the second floor of the mill and automatically dumped. The rock 

 passes through a Butterworth & Lowe cracker and nipper, there 

 being two of each, and is thus ground to 3^ inch. It is then ele- 

 vated and fed by a screw feed into two Cummer kilns equiipped 

 with American automatic stokers and with a Bristol recording 

 thermometer, which records on a paper in red ink tlie time and 

 temperature. The dust is separated in the furnaces by an air blast, 

 and is said to make a high grade of land plaster. From the kilns 

 the steaming gypsum is carried by screw conveyors to the large 

 bricked-in coding bins where it is allowed to finish cooking for 

 24 hours or so. The kilns can each calcine about 11 tons an hour. 



