Quintant marked "Adams London", circa 1840

quintant and case

Quintant; frame brass marked "Adams London", dated ca 1840?; scale silver graduated -2 deg. to 149 deg. by 1 deg. subdivided to 20'; index arm w/swinging magnifier; vernier reading to 15'; tangent screw; index mirror with 3 shades; adjustable horizon glass with 2 shades; adjustable sight vane for telescope; 3 screw on brass legs; screw on wooden handle. Measuring to 136°.