Brass framed sounding quintant.

Sounding quintant with 6-inch radius limb, diamond-pattern anodized brass frame and silver inlaid scale marked -5° to 195° (169° range), 30 arc-min. divisions' with silver vernier scales to 1 arc-min. with wooden handle and Mahogany keystone box containing in the lid a label for Henry Porter (successor to William Cary), made by (William) Cary, London, 1855-1865. Fitted with tangent and clamping screws at back of the index arm; no shades; index-glass and horizon glass with screw and capstan screws adjustment; Detached telescope, (78 mm large objective) erect image with bracket without adjustment. Accessories include Screw-on diaphragm for the telescope; adjusting key; adjusting pin and magnifying glass (missing).