Abstract

Few accounts have survived detailing the techniques employed for the production of optical glass for astronomical and microscopical instruments during the seventeenth century in Italy; the period during which the art was being developed in the shops of Eustachio Divini and Giuseppe Campani, and other optical instrument-makers. Indeed, few of the tools of the lens-makers have been described in any detail, and few if any have survived. Consequently, the discovery of a hitherto apparently unknown Italian treatise, or what appears to have been notes for a shop manual of the period, is a contribution to present knowledge of lens-making technology even though the identity and region of the author remain unknown