<P> Robert Grosseteste's treatise De iride ("On the Rainbow"), written between 1220 and 1235, mentions using optics to "read the smallest letters at incredible distances". A few years later in 1262, Roger Bacon is also known to have written on the magnifying properties of lenses . The development of the first eyeglasses took place in Northern Italy in the second half of the 13th century . </P> <P> Independently of the development of optical lenses, some cultures developed "sunglasses" for eye protection, without any corrective properties . Thus, flat panes of smoky quartz, were used in 12th - century China . Similarly, the Inuit have used snow goggles for eye protection . </P> <P> The first eyeglasses were made in Northern Italy, most likely in Pisa, by about 1290: In a sermon delivered on 23 February 1306, the Dominican friar Giordano da Pisa (ca . 1255--1311) wrote "It is not yet twenty years since there was found the art of making eyeglasses, which make for good vision...And it is so short a time that this new art, never before extant, was discovered...I saw the one who first discovered and practiced it, and I talked to him ." </P> <P> Giordano's colleague Friar Alessandro della Spina of Pisa (d . 1313) was soon making eyeglasses . The Ancient Chronicle of the Dominican Monastery of St. Catherine in Pisa records: "Eyeglasses, having first been made by someone else, who was unwilling to share them, he (Spina) made them and shared them with everyone with a cheerful and willing heart ." By 1301, there were guild regulations in Venice governing the sale of eyeglasses . </P>

When was the first pair of glasses invented