Imaging through the Oberhaeuser Drum Microscope
The diatom slide as imaged through the low magnification lens.
Diatoms as imaged by the higher magnification objectives and eyepiece. The highest magnification eyepiece includes a reticle. The scale in this image is the reticle.
Image of a micrometer scale (A) and the reticle (B). Magnification is approximately 100x.