Augsburg, beg. of 18th cent. Octogonal gilt brass case partly engraved. Centre with compass surrounded by a silver dial with 3 circles of arabic resp. roman numbers. At the rim labeled "Horizontale Sol & Luna". Underside sign. "Johann Martin in Augsburg" and engraved pole height of several European towns. In original leather case. 6,5 x 6,5 cm. - J.M. also known as Johannes Martinus, since 1669 in Augsburg self-employed watch maker esp. known for his astronomic watches. Exhibits in the Dennison Collection, in Mus. Beyer of Zürich as well as in the National Mus. of München (Comp. Baillie, S. 211).