Description

Standing 14 inches tall (16 inches fully racked), this instrument was intended to be an easy to use petrographic model for the student or professional. Made to the specifications dictated by George H. Williams, professor of minerology and inorganic chemistry at John Hopkins Hospital/University, it exhibits a few innovations of the time. c.1890.

Bearing patent dates of 1876 and 1885, it is a pleasing combination of black enamel and bright, golden lacquer (99% intact).

Three leg design (chips to feet), double trunnion, substage racked double polariser (one tooth of rack worn), fully rotatable round stage, engine divided into 360 degrees (as is the polarizer-all signed), it has an unusual mechanical stage operated by two knurled knobs near the curved  arm. Coarse and fine adjustment are flawless. Double sided, swinging 2 inch mirror (80% to concave side) and a body tube with sliding  polarizer and analyzer (Nicol prism) with two spaces for Bertrand and wave? plates (absent). Double rotating nosepiece with  1/6 and 1/8 inch objectives (may have a 2-3 inch as well), all signed in canisters with early script signatures, rather than 20th C. block style lettering. One eyepiece in brass, the microscope gives good images (dusty).

This FLD 6 model, according to the 1896 B&L catalogue pp.46-47 had a base price of $25 USD and with accessories, $45. No case. Dr. Williams wrote an article in the American Journal of Science in Feb. 1888 pp. 114-117 as to the use and attributes of this compound monocular microscope. I believe this is one of their earliest examples as it is NOT serialised.