The grinding motion of the machine is supplied to the lower member while the upper member remains stationary. In the patent letter, Scott says that the objectives for his dental grinder are to reproduce the measurements that were taken from the patient and to obtain a balanced occlusion in both protrusive and lateral movements without interferences. Therefore, the grinder is provided with adjustable condylar controls with curved pathways to reproduce the condylar inclination of the patient. Furthermore, the mandibular cast positioned in the grinder “from measurements taken from the mandible of the patient”. (He does not elaborate on this.) For some reason, he ignored the incisal guidance feature. During the grinding procedure, tension is maintained between the denture teeth by a spring or rubber band located in the position where the incisal pin would be. The grinding action is reciprocal through the condylar controls and produces a somewhat elliptical pattern The original patent describes a plaster less mounting of the casts with screws
Dr. Edgar N. Starcke's articles in the Journal of Prosthodontics have more information on the history of articulators.