[Guidonian Hand] Mano per il Canto Fermo - Original Drawing, ca. 1700A fascinating and unusual drawing. Laid paper, no discernible watermark (just the tip of something, not identifiable), but certainly late 17th to early 18th century. 3. 5 x 5. 2 inches. 9 x 13 cm. The drawing is reminiscent of diagrams found in Italian books of the seventeenth and eighteenth centuries, though this particular one does not appear to be based on a known printed exemplar. Though it is in some senses a standard Guidonian hand, it only