US775600A Rotary cementkiln. Google Patents
US775600A USA USA US775600A US 775600 A US775600 A US 775600A US A US A US A US A US A US A US 775600 A US775600 A US 775600A Authority US United States Prior art keywords kiln gun rotary valve aggregates Prior art date Legal status (The legal status is an assumption and is not a .