Traite de con uite de la famille



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(Eventually each of the neat examples shown here will appear again accompanied by a detailed description.)







We generally take for granted one of the world’s most important inventions – spectacles. Imagine what life would be like not being able to see images clearly or sharply. According to a January 11, 1999 feature article in Newsweek Magazine , reading glasses are one of the most important inventions of the past 2000 years. They developed because of the work of artisans, like glassmakers, jewelers and clockmakers, along with some of the most brilliant scientific minds over the centuries. According to Dr. J. William Rosenthal, "Philosophers, monks, mathematicians, physicists, microscopists, astronomers, and chemists all played vital roles in developing this instrument." 1




No one really knows about the early history of image magnification. In ancient times, someone noticed that convex-shaped glass magnified images. Sometime between the year 1000 and 1250 crude technology began to develop regarding reading stones (simple magnifiers). English Franciscan Friar Roger Bacon (1220 -1292), in his 1268 ‘Opus Majus’, noted that letters could be seen better and larger when viewed through less than half a sphere of glass. Bacon's experiments  confirmed the principle of the convex (converging) lens, described by Alhazen (965-1038) Arabian mathematician, optician and astronomer at Cairo, and even earlier by the Greeks. Bacon recognized that this could assist weak eyes or the vision of aged persons.






Early recorded evidence demonstrates that glasses first appeared in Pisa, Italy about the year 1286. Technically, they were formed from two primitive convex shaped glass/crystal stones. Each was surrounded by a frame and given a handle. These were then connected together through the ends of their handles by a rivet. They were not really an invention per se but instead a bright idea or "adaptation" of something used earlier - the simple glass stone magnifier. Essentially someone took two existing mounted stones and connected them with a rivet. Most likely, this first pair of glasses were invented by a lay person who wanted to keep the process a secret in order to make a profit. This individual was a true visionary (no pun intended). Two monks from the St. Catherine’s Monastery, Giordano da Rivalto and Alessandro della Spina, provide the earliest (primary source) documentation to support this fact. On Feb.23, 1306, Giordano mentioned them by stating in a sermon "it is not yet twenty years since there was found the art of making eyeglasses which make for good vision, one of the best arts and most necessary that the world has." He coined the word "occhiali" (eyeglasses) and its use began to spread throughout Italy and Europe. Friar Spina’s 1313 obituary notice mentions, "when somebody else was the first to invent eyeglasses and was unwilling to communicate the invention to others, all by himself he made them and good-naturedly shared them with everybody." Salvino D’Armato Degli Armati of Florence was at one time thought to be the inventor of eyeglasses but this claim has been proven to be totally false.




It is not surprising that spectacles would receive a major impetus for their future development in regions where other glass objects were being produced. At that time Venice, Italy (the island of Murano specifically) was one of the most advanced centers for the medieval glass industry, its guild of crystal workers officially created in November 1284. In one of the guild’s earliest regulations adopted in April 1300, the organization adopted a term for the discs for the eyes ("roidi da ogli" or "vetri da occhi") for the first time.




 

But it was definitely the city of Florence that by the middle of the fifteenth century led in innovation, production, sale, and spread of spectacles within and outside Italy as attested by documents already or soon to be published. In particular, Published evidence in the form of letters of the dukes of Milan, Francesco and Galeazzo Maria Sforza, dated 1462 and 1466 respectively, reveal the first detailed information about spectacles since their invention; namely, 1. Florence was producing in large quantities not only convex lenses for presbyopes, but also concave (diverging) lenses for myopes (i. e., about a half century before the latter were thought to have been developed); 2. Florence had become the leading manufacturer of readily available and affordable good-quality spectacles; 3. Florentine spectacle makers were well aware of the fact that visual acuity declines gradually after the age of thirty, and were constructing lenses progressively graded in five-year strengths for hyperopes or presbyopes and in two strengths for myopes, practically prescription lenses; 4. The dukes of Milan were ordering prestigious Florentine glasses by the hundreds to give them away as gifts to their courtiers, the first record of such a phenomenon in the literature. The massive documentation available only in Florence for this early period has revealed the name of fifty-two spectacle makers between 1413 and 1562 and the location of their shops. Other centers of production such as Venice, Germany, France, Netherlands, and England began to appear more frequently in the sources only in the sixteenth century but they never produced anything near the quantity of the Florentine documentation until well into the seventeenth century. The documents from Florence and other places will be discussed along with archeological evidence recently discovered in various digs in Europe in the forthcoming book, "Renaissance Vision from Spectacles to Telescopes," by Vincent Ilardi". (Translations of the two key 1460's letters)

 

During this period of time, spectacles were both cheap and plentiful. Ordinary “run-of-the-mill” spectacles cost the buyer just 2 or 3 soldi (shillings). Middle priced ones were selling for 6 to 18 soldi. The finest examples with quality crystal/glass lenses and gold or silver frames were priced at 1 ducat (the equivalent of 82 soldi). So who could afford them? As an example, a mason from Florence in the 15th century made 17 soldi per day so multiple pairs were frequently ordered. They were not the expensive vision aids of the clergy, the wealthy, and intellectuals, but instead were extensively used by artisans as well. Almost everyone over forty had to have recourse to them without eliminating entirely the need for magnifying lenses and concave mirrors for close work. In fact, documents show that by the end of the 14th century thousands of spectacles were being exported from country to country throughout all of Europe.




The oldest known pictorial representation of eyeglasses is a fresco in the Chapter House of the Dominican Monastery attached to the Basilica of San Niccolõ in Treviso. It was painted by Tommaso da Modena (1325-1379) in 1352 and shows Cardinal Hugh of Provence (1200-63) wearing a pair of rivet spectacles. What makes this painting interesting is the fact that the Cardinal died before glasses were invented but the painter added spectacles to his fresco as a sign of old age and scholarship. Domenico Ghirlandajo included spectacles in his painting of St. Jerome at his desk in 1480 as a symbol of scholarship. For this specific reason and since he was the first person to translate the bible into Latin, St. Jerome (340 – 420 A.D.) was adopted as the patron saint of scholars……and by the French as the patron saint of spectacle-makers.



The earliest glasses discovered thus far have been an incomplete pair of rivet spectacles found under the floorboards of the nun’s choir-stalls during the 1953 renovations to Kloster Wienhausen in northern Germany. Other similar finds dating to the early 15th century have since been made at a former trash site in Freiburg, Germany (two very early pair) and in London (both the "Trig Lane" spectacles and the "Swan Stairs" spectacles). In the Netherlands, in 1986, a nearly complete pair was unearthed in Windesheim, and another was found in 2001 in Bergen op Zoom.


 

The 15th century marks a crucial time in the development of spectacles. By the time of Johann Gutenberg’s invention of the printing press around 1450, glasses were already used by artisans as well as monks and other religious scholars. Then once books were made available to everyone, the demand and subsequent popularity of spectacles rose dramatically. By the end of the 15th century, spectacle peddlers who were selling glasses was a common sight on the streets of Western Europe. People often rummaged through baskets filled with German metal and leather spectacles in an effort to improve their vision. The purchaser tried on several pair and finally selected the one of his preference. This demand increased exponentially after 1665, when the first newspaper, the London Gazette, appeared. All classes of Spanish people thought that wearing spectacles made them appear more dignified and important. The possession of Florentine glasses was also considered a status symbol. After all, early ones had been the prized possessions of churchmen, wealthy scholars, artisans, and high-class individuals of the medieval world. As a result, people in Spain, Italy, and even China regarded eyeglasses as a sign of superior intelligence and nobility.



In the Far East, spectacles had a different development. They were brought in by Western European merchants and missionaries in the early 15th century. Everything was by trial and error and the larger the spectacle the more influential the man since they reflected social status more than a need for vision correction. In Asia, these eyeglasses were attached to the ears by loops of cord; a concept originally noted around 1500 in Spain and called threaded (thread loop) spectacles. Occasionally weights were applied to the end of the cords which then hung over the back of the ears. In China, tea-colored sunglasses were introduced and used to treat conjunctivitis. This was a "cool mass when placed near the eyes" and therefore was soothing to the wearer. They were large and rested on the cheeks because of the facial anatomy of the Chinese.



Though roughly made, early spectacles were full of charm and rapidly became a symbol of wisdom and learning. Later glasses quickly became more technically sophisticated. One of the most important industries, the German spectacles industry, was formulated in 1535 with the issuance of regulations of the Nuremberg spectacle makers’ guild. In London in 1629, King Charles I granted a charter incorporating the Worshipful Company of Spectacle Makers. Unfortunately all of their earliest records were destroyed in the Great Fire of London in 1666 except for that charter. During most of the 17th century, Germany remained the center of spectacle making. Germans made the finest frames while the Italians made the highest quality lenses. The early lenses were still cloudy until manufacturing developed and flint was added to make the glass clearer. Genuine, original pre-1700 spectacles are exceedingly rare today and are highly treasured by museums and collectors alike.
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