A vat used for bleaching cotton, dyeing cloth or yarn, or processing paper pulp.
Sometimes called a keeve, but 'keeve' is a wider-ranging term (it can also mean a brewing tub for mash, or a vat for dressing ores).
Kiers can be spherical (neat!) or cylindrical, and are still in use today.
Etymology: From the Old Norse ker, vessel or vat.
"Hitherto it has been customary when employing round kiers for the bleaching process, to fill the boiling kier by hand, and after the boil was complete, to remove the cloth from the boiling kier into the chemical and acid tank again by hand, which method necessitated the employment of a number of skilled piling boys, a considerable loss of time in filling the kiers, faulty bleaching, and repeated handling by the operatives of the whole of the pieces attached together....The improved plan for carrying out said method includes a round iron kier, a round wood kier, an expander, a white mangle and a folding device arranged in a row, in combination with an automatic piler arranged over each kier..."
- from Color Trade Journal and Textile Chemist: Devoted to the Interests of the Manufacturers and Users of American Dyestuffs and Processors of Textile Fibers and Fabrics, vols 11-12; 1922.