BLAGRAVE, John. The Mathematical Jewel, shewing the making, and most excellent use of a singular instrument so called ..., London: Walter Venge, [1585]. Small 2°, title with a large woodcut of an armillary sphere by Blagrave, numerous woodcut illustrations and diagrams, many by Blagrave, woodcut initials (lacking leaf with large cut of a jewel on each side and folding plate of fixed stars, margins of title cut down and mounted, final leaf re-margined with dark paper, closed tear to A4, lightly browned throughout), modern goatskin (spine label chipped). FIRST EDITION. STC 3119.