1841. Two works in one volume, 8vo; pp. 40, with woodcut title-page vignette and three folding engraved plates depicting 11 figures, plate III signed by the author at the tail, lower folds of plates all a little dust-soiled with minor repairs to folds; pp. 16; both works a little foxed, more prominent on first and last leaf of pamphlet, with lower corners nicked throughout; authorial presentation inscription at the of second title-page; in later blue wrappers. Bound together, presentation copies of two short optical treatises on vision. Of Fenomeni della visione, Becker notes: ‘The volume consists of a letter by Luigi Brenta, an optician in Milan, to an unnamed physicist, followed by the description of Brenta’s optical experiments and observations. His investigations concern electromagnetic force in the eye, divergency of light-beams, and images on the retina. This copy of the book is bound in its original printed wrapper and was signed by the author on the bottom of the third plate’ (Becker Collection in Ophthalmology, 60.3 online catalogue).