GRIMSLEY. | Technology of Gypsum. 103 
tities. Weir-Pittsburg coal and coals from Colorado and Arkan- 
sas are the favorite fuels in the Kansas gypsum fields. 
The great objection to the present kettle system of calcining 
gypsum is the great amount of heat required to calcine the mass 
of cold gypsum thrown into a kettle with thick steel bottom. 
Much heat is wasted by radiation from the kettle. Another 
objection is the large horse-power required to stir this mass of 
gypsum, and so’‘keep it from overburning at the bottom. The 
great heat required tends to warp and burn out the kettle bot- 
toms, which are heavy and expensive to replace. The methods 
of calcining gypsum have not improved much recently, and it 
would appear that there is room for improvement. The im- 
provements made are looked upon with distrust. Kettles have 
been invented in the last few years for continuous calcining, 
and the product made was of good quality ; but when the method 
of burning was discovered, the dealers made claims for rebate 
on the plaster, claiming it was not satisfactory. Tests on these 
plasters are said to have shown they were of good quality. It 
is to be hoped that these prejudices will be removed, and that 
plaster machinery will improve as machinery in other lines 
has improved. 
THE MULVANE PLANT. 
The Mulvane plant is the most recently constructed one in 
the state, having begun operations about January 1, 1899. In 
some respects, also, it is the most nearly an ideal type of a plant 
known in the West, as it combines to a high degree the latest 
devices for labor saving and for conveniences in handling the 
raw material and the finished product. 
The plant, of two kettle capacity, is located immediately at 
the mines, with a switch from the Augusta branch of the Atchi- 
son, Topeka & Santa Fe railway passing alongside the build- 
ings. A little stream cuts through the gypsum deposit, leaving 
the larger and better material on the south bank, with a con- 
siderable amount on the north. The buildings, three in num- 
ber, are located on the north side of the stream; and are the 
calcining building, the power house, and the warehouse, to the 
former of which is attached a coal shed on the east (12 by 48 
