Important for every bookbinder and bookbinder's spouse that wants to spare the other aggravation!
New [Wilhelm] Leo's Paste Clump Eliminator
Solid construction, won't rust, easy to use.
Turn the handle with knob and all the paste clumps will be eliminated and your paste will become beautifully smooth. Tested and recommended by professionals. No workshop should be without.
From the Allgemeiner Anzeiger für Buchbindereien, 1900.
Can't find one, get an applesauce mill.