pug mill

a mill for grinding and mixing materials, as clay or the ingredients of cement, to a desired condition.

Origin of pug mill

First recorded in 1815–25

puffery, puffin, puffin crossing, puffy, pug, pug mill, pug nose, pugachov, pugaree, pugdog, puget

In some cases it has been found necessary to mix the ingredients in a pug-mill, as in mixing clay, &c. for bricks.

A Dictionary of Arts, Manufactures and Mines |Andrew Ure
It is then strained and finally passed through a pug-mill, and is ready for use.

The Ceramic Art |Jennie J. Young
These two processes are now generally performed by one machine, consisting of pug-mill and brick press combined.

Encyclopaedia Britannica, 11th Edition, Volume 4, Part 3 |Various
It then passes into a pug-mill into which superheated steam is admitted, and by this means is converted into a plastic paste.

Scientific American Supplement No. 360, November 25, 1882 |Various