Astronomy.- Marius (Simon) Mundus Iovialis Anno M. DC.IX detectus Operspicilli Belgici, woodcut arms within typographic border to verso of title, woodcut diagrams, head- and tail-pieces and decorative initials, final f. blank, lacking )( )( )(^1&2 (includes the portrait), some staining, mostly at start, later binding using a medieval manuscript, short split to upper joint, small 4to, Nuremberg, Johann Laur, 1614.

⁂ First edition of this work reporting the discovery of the satellites of Jupiter, which Marius made two months before Galileo Galilei. In the preface Marius gives an account of the acquisition of his telescope from a Dutch seller at the Frankfurt Fair of 1608. Galilei had constructed his telescope in 1609 from descriptions of Dutch instruments passed on to him. Rare at auction, with the last copy we can trace offered in 1977.