8vo (164 x 104 mm). Woodcut device on title-page, woodcut printer's device at end; text in Greek and Latin; woodcut diagrams throughout. (Some minor browning or spotting, inkburn to the upper margin of a few leaves.) Contemporary vellum, yapp edges, hand-lettered on spine (lacking ties, soiled); quarter morocco folding case. Provenance: extensive early mostly marginal ink notes and diagrams. 
 
Reprint of the first Gracilis edition of 1557 incorporating the corrections from that edition. The woodblock vignette on the title-page and the printer's device at end depict the coat-of-arms of Jerome of Marnef. Adams E-1001.