B02—CRUSHING, PULVERISING, OR DISINTEGRATING; PREPARATORY TREATMENT OF GRAIN FOR MILLING
B02C—CRUSHING, PULVERISING, OR DISINTEGRATING IN GENERAL; MILLING GRAIN
B02C4/00—Crushing or disintegrating by roller mills
B02C4/10—Crushing or disintegrating by roller mills with a roller co-operating with a stationary member
B02C4/18—Crushing or disintegrating by roller mills with a roller co-operating with a stationary member in the form of a bar
B02C4/22—Crushing or disintegrating by roller mills with a roller co-operating with a stationary member in the form of a bar specially adapted for milling paste-like material, e.g. paint, chocolate, colloids
George Byron Gordon: The Hieroglyphic Stairway. Ruins of Copan. Report on Explorations by the [Peabody] Museum [Memoirs of the «Peabody Museum» of American Archaeology and Ethnology