Early history of lenses

Surprisingly, little is known about the history of the early development of lenses and mirrors, and especially the early utilization of spectacle lenses and magnifiers in Spain and its New World colonies. Calvo and Enoch already have evidence for the use of spectacle corrections in Spanish-America much before their use in other European settlements in the New World. And they also have published early utilization of spectacles in Spain associated with the Renaissance sculptor Gil de Siloe in Burgos.

We reviewed the literature as it pertains to Luis de Velasco, a painting of this gentleman wearing spectacles is (was?) on display at the National Historical Site at Pecos, New Mexico and the original painting is at the Gallery of Viceroys, Castillo de Chapultepec, Mexico DF.  Luis de Velasco was an early Viceroy of the South-Western area of the future USA as well as Florida. A survey conducted at the Archivo General de Indias in Seville revealed over 10,000 citations referring to de Velasco. These references are not necessarily related to the technical aspects of use of spectacles and other modern tools, but may be to military, economical and domestic facts related to the actual government at the Florida colony.

Separately, in 2000, Prof. Enoch was given the privilege (by le Louvre, Paris) of studying some of the World´s oldest known lenses (about 4600 years old) from the Fourth Egyptian Dynasty (Old Kingdom). Both the unique reserve eye E-3009 (top open, lens visible and accessible with the possibility of studying the optics), and the eyes/lenses of the masterful statue, "Le scribe accroupi" were studied in detail. Now that the applicable data have been analyzed, papers are being prepared. These remarkable and high quality lenses with both convex and concave ground surfaces have a built-in visual illusion. The observer reports the lenses of these eyes "follow the observer" in any direction. Clearly, in spite of their age, these remarkable lenses are too complex to have been the earliest of lenses!

And utilizing sources already available, as well as others sought, we have the material to begin the task of defining the early history of lens use in Spain as well as in the Spanish colonies in the New World and Pre-Columbian American civilizations. Also we seek to assess early use of lenses by Spaniards who lived elsewhere, (e.g.,, by Seneca in Rome, who lived shortly after the birth of Christ). Seneca reported (1) the earliest recorded lens-based visual correction for presbyopia, (2) he was very familiar with magnifiers, and (3) he discussed use of mirrors for visual corrections and magnifiers - in particular, use of items employed by others. These reports appear in a group of tracts written by him titled, Natural Questions.

An important issue to be studied is the existence and development of pre-Columbian technologies in the American continent. There are nowadays pertinent data indicating a clear knowledge on optical properties of surfaces to be used as specular ones and mirrors with remarkable quality. An interesting example is the anthracite mirrors as developed by the Chavin culture ( a pre-Incan culture developed in later Peru). Our laboratory has obtained anthracite mirrors and studied the main characteristics regarding reflecting properties. This fascinating results continuous in motivating us for further work in collaboration with Prof. Jay M. Enoch.