■50 NEW YORK STATE MUSEUM 



crackers and again elevated to the bins over tihe calciners. From 

 the bins it passes into two large Cummer rotary calciners each with 

 a capacity of 15 tons per hour. The dust from the calciners is 

 collected in overhead bins and with the finished product from the 

 calciners is elevated and passes into the brick-inaliosed cooling bins. 

 After remaining in these bins 24 hours the material is groimd in 

 four Sturtevant rock emery mills. It is then elevated and car- 

 ried to the mixing room in the west end of the building. This is 

 equipped with two three-compartment Broughton mixers, a large 

 stucco bin, a fiber machine and a hair picker. Power for the mill 

 is furnished by a 300-horsepower Allis-Chalmers motor. The mill 

 and mine are operated day and night w.ith a capacity of 500 tou's 

 for each 24 hours. 



Additional occurrences in Genesee county. West of Indian 

 Falls and 8 miles west of Oakfield, gypsum outcrops along the 

 banks of Tonawanda creek. The stream cuts down through the 

 escarpment and exposes the limestones and the underlying gypsum 

 beds. A 6-foot layer of gypsum is exposed along the creek from 

 I to 2 miles west of Indian Falls and about 30 feet above the 

 creek, while above it lies an 8-foot layer of a more impure and 

 harder gypsum. 



The deposits are included within the Indian Reservation ; in 

 1901 the Standard Plaster Co. secured the m'ineral right to the 

 whole tract and began mining operations. Tunnels were driven 

 into the 6-foot layer, using Howell's twist drills and black pow- 

 der. The rock mined was loaded on flat mine cars and pushed 

 by 'hand to the tunnel entrance where the good gypsum was loaded 

 on cars and the waste rock thrown on the dump. From the mines 

 the rock was carried by a railroad switch to the main line of the 

 West Shore near Alabama, the switch being 3 or 4 miles long. 

 The rock was then sent to Black Rock where thie company had a 

 mill equipped with a gyratory crusher and screen, one Cummer cai- 

 ciner, one cooling bin and five Sturtevant emery mills. The power 

 was electric. The mines are now completely abandoned. Under- 

 ground water and the presence of mud pockets are said to have 

 been the main difficulties in the way of success. Similar trouble 

 is encountered in nearly all gypsum workings, and it seems plausible 

 that the conditions in the latter respect at least would have im- 

 proved with the extension of the tunnels for 'some distance under 

 the hill. The beds could also be worked through sbafts. 



The known gypsum beds of the Akron district begin 2 miles 

 west of this locality. These will be discussed under Erie county. 



