Bracket with a double-tailed mermaid at each end. Slot in bracket bordered by 2 scales of equal parts, 0-12 subdivided into 12ths. Clamps for grasping round objects slide in the slot. Locking screws to secure clamps also serve as feet of instrument; covered with rows of overlaid leaves and little feet in relief. A mascaron at base of each clamp's bracket. Each pincer pierced with a stylized dolphin and scrolling leaves. Tightening nuts and bolts for pincers designed as leaves and flowers. Perhaps used as an optical bench.