Fleaglass microscope & Telescope Compendium, 18th C

Fleaglass microscope & Telescope Compendium, 18th C. An European, 18th Century Compendium, constructed from bone, comprising 3 sections with each piece has a Lens to make a small low powered telescope, a loop type magnifier and a fleaglass magnifier, with 2 screw on end caps.The first section of the body has a convex lens with a mounted fleaglass, which also acts as a diaphragm fleaglass. The small, high-power lens in the bone ring has a specimen pin at the correct focal distance. This section also has a magnifier function the second section has a concave lens and the last section has a convec lens. The bone and the lenses are in good condition, with only two very fine hairline crack. Length 13 cm