refractory clay

This reflector terminates above in a dome, in whose center is placed a refractory clay box.

From Scientific American Supplement, No. 417, December 29, 1883 by Various

A refractory clay sleeve, 41, protects the lower part of the cylinder, 15, from the fire, and diminishes the smoke passages at 42.

From Scientific American Supplement, No. 483, April 4, 1885 by Various

Generators.—The generator consists of a retort made of refractory clay, vertically mounted, and cylindrical or conical in form.

From Gas-Engines and Producer-Gas Plants A Practice Treatise Setting Forth the Principles of Gas-Engines and Producer Design, the Selection and Installation of an Engine, Conditions of Perfect Operation, Producer-Gas Engines and Their Possibilities, the Care of Gas-Engines and Producer-Gas Plants, with a Chapter on Volatile Hydrocarbon and Oil Engines by R. E. Mathot

The hot air stove should be well lined with refractory clay, in order to prevent the iron from getting red hot, and the grate should be of relatively wide surface.

From Scientific American Supplement, No. 514, November 7, 1885 by Various

The reliefs, so finely modelled by Flaxman, were fired, and from them moulds of a very refractory clay were made, called pitcher moulds.

From Pottery, for Artists Craftsmen & Teachers by George J. Cox