eckel.] NEW YORK. 257 
In the fall of 1890 operations were commeneed at Montezuma, N. Y. 
The company owned 1,700 acres of land, underlain by a deposit of 
marl and clay, which varied in thickness from •! to 20 feet. The 
deposit lay below the level of Cayuga River and near its shores. It 
was overlain by several feet of muck, which was first dredged off and 
used for filling and grading for a railroad. The marl and clay had a 
rather uniform composition, and it was therefore found practicable 
to excavate both materials by machinery. The bucket of the steam 
dredger employed brought up a ton every three minutes. Cars were 
run on the track under the bucket of the dredge to receive the material, 
and the loaded cars were then run on platform scales and weighed. 
The marl, containing about 50 per cent water, was drawn by a steam 
hoist up an ineline into the second story of the works and above the 
upper end of a mixing machine, into which the load was dumped 
without drying or any other preliminary treatment. At the same 
time a weighed and ground portion of clay was added to standard- 
ize the mixture. The materials mixed as they gravitated toward the 
lower end of the machine. The entire process was practically con- 
tinuous, a fresh charge being added at the upper end of the mixer 
every ten minutes, while an equal amount was being gradually drawn 
off from the lower end in the same space of time. The mixture then 
passed to a stone mill that completed the mixing and ground any coarse 
materials. From the mill the mixture was introduced directly by a 
screw conveyer into the rotary kiln, oil being used as fuel. This was 
unique not only in its length, 75 feet, but in having opposite its lower 
end a gas retort or combustion chamber. This chamber was heated 
by a coal tire and vaporized the oil as it was sprayed into it. The air 
blast also passed into this chamber, coming from a rotan r fan blower. 
In the first volume of Mineral Industry Mr. W. A. Smith gives the 
following interesting contemporary account of this kiln: 
Duryee's revolving furnace consists of a sheet-iron cylinder, 75 feet long, inclined 
• toward the firing end § inch to 1 foot. The lower hot end is 6 feet in diameter for a 
length of 20 feet, and is lined 9 inches thick with a mixture of ground fire brick 
and molasses. The remainder of the cylinder, 55 feet long, has a diameter of 5 feet, 
and is lined with 8-inch fire brick. Only the lining at the hot end requires renewal, 
and this can be replaced in ten hours, at a cost of $25. The cylinder revolves on 
cast-iron rollers three times a minute. The power required is 5 horsepower. 
At the lower end a small coal fire is kept up on a grate, but the chief fuel is crude 
petroleum, introduced in a jet which meets the hot-air blast. The consumption of 
oil is 8 gallons per barrel of cement clinker produced. Fifteen barrels of oil are 
required to heat the furnace ready for burning cement. 
The clay and marl are mixed wet and run in as a slurry at the upper end. The 
mixture in drying forms a sand, which moves slowly downward with the turning of 
the cylinder, and is finally discharged at the lower end as cement clinker of the size 
of small gravel. It takes two hours to run the particles through. The operation is 
continuous, and the product is 250 barrels per day. It is claimed that all the mix- 
ture is burned to Portland clinker. 
Bull. 243— 05 17 
