Authentic Antique Kelvin, Bottomley and Baird Ltd. Marine Sextant

Description

MARINE SEXTANT BY KELVIN BOTTOMLEY & BAIRD Beautiful antique sextant made by Kelvin Bottomley & Baird Ltd. With some limited research on this company, I've learned they made some of the finest nautical tool and equipment ever. I believe this piece dates to the early 1900's. Marked " KELVIN BOTTOMLEY & BAIRD LTD. GLASGOW No. 9338". Comes in original mahogany wood box . Much of body is made of brass, also has mahagany base. All attached lenses and parts are present. None are broken or cracked. Optics appear to be clear and in good shape. Also comes with 3a eyepieces. Box has  Certificate of examination label still on inside of top dated June, 1920. Large arm moves freely and stop screws work. Truly a rare collectable, everything appears original. Please ask any questions as I am not an expert on these device, but have tried to give honest, accurate description. Same type sold at auction at Christies without the box for over ,500.00.
Box measures 11.5 inches by 12 inches by 5 inches
BRIEF HISTORY OF INVENTOR: William Thomson (1824-1907), Lord Kelvin of Largs
William Thomson was a mathematical physicist, engineer in the physical sciences of the 19th century. He did work in the mathematical analysis of electricity and thermodynamics, and did much to unify the emerging discipline of physics in its modern form. He is widely known for developing the Kelvin scale of absolute temperature measurement. In 1892, the title Baron Kelvin was given in honour of his achievements, and named after the River Kelvin, which flowed past his university in Glasgow, Scotland.
He also enjoyed a second career as a telegraph engineer and inventor, a career that propelled him into the public eye and ensured his wealth, and, fame and is widely known in the marine industry for his work.