Field Pocket Microscope With Slides. This is a small antique brass microscope with its original lacquer. It is composed of a X40 ocular lens, X10 condenser lens and spring held slide stage. Glass slides with the object of research are inserted through a lateral slit and held constant by the pressure of the spring held slide stage. Rotating the ocular eyepiece makes focal length adjustments. Included are 8 slides of biological and other materials.