ACCESSORY: TOLLES-TYPE CAMERA LUCIDA as supplied with a C.X. Dalton Microscope

The camera lucida supplied with the Dalton Student microscope was designed by Robert Tolles, and reflects an interesting variation in the design of the camera lucida. It makes use of a truncated cone as its optical unit. The device is used with the microscope in a horizontal configuration. The sides of the cone are blackened. In use, the observer orients the smaller flat face of the cone at a 45 degree angle from the paper, with the larger face on the side of the eyepiece angled also at 45 degrees. The image from the microscope is reflected off the larger end, while the image on the paper passes at an angle through the botttom, and is directed to the observer's eye.