Two casts, obverse and reverse, of a commemorative medal. Obverse: Inscribed: 'AO : CHR : M . DC . LXXXXI . REGNANTE REGNUM OPTIMO . CHRISTIANO QVINTO . VIRTUTE ET INDUSTRIA HENRICI SPAN INVENTA EST NAVALIS MACHINA CUIUS OPE VETUSTAE ET LONGO USU FRACTAE NAVES NON SINE MAGNO TEMPORIS ET SUMTUUS COMPENDIO RESARCIRI, ET QVASI IN INTEGRUM RESTITUI QVEANT . ADEO QVOD NATURA NEGAVERAT COMMODUM ARTE PARATUM EST.' (In the year of Christ, 1691, in the reign of the excellent King Christian the Fifth, by the virtuous industry of Henrik Span, the naval machine was invented, by the means of which ships old and damaged by long use can be repaired and restored almost as new, with great economy in time and expense; and so the convenience which Nature refused has been provided by art.) Reverse: the dry dock with a warship in it. Exergue: 'HAC MATRE RENASCOR' (from this mother I am born anew). The opening of first Danish dry dock.