Close-up of one of the gear motors, both being identical. Bristol Motors has been superceded by Cramer Co. The motors have been futher identified as standard clock drive motors used by the Cave Optical Co; and futher supports the belief that the mounting is by Cave. The motors are 115 Volt 60 cycle 4 Watt units running at only 1 rpm. Since this image has been taken we have located several replacements and will soon be installed.