Traite de con uite de la famille

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After supplies gave out in Europe and Russia, rock (quartz, beryl, or pebble) crystal, mined in Brazil and Argentina, was used because this hard material was more durable than regular glass. Craftsmanship and great skill were required to make each individual lens. Once the lenses were ground and polished, they were fitted into the frames. All early lenses were positive or convex and spherical. On the other hand, concave lenses for the nearsighted came into use in Florence in the middle of the 15th century. During the 17th century tinted lenses first became popular. Round lenses were almost universal until the end of the 18th century when oval lenses became fashionable. Frames went through a similar evaluation and evolution. The earliest frames were made of wood, horn, or bone. Leather frames had a relatively short life span from the 16th to the middle of the 18th century. Few have survived to present day time and those are highly sought after. The first frames were for round lenses, followed by oval, and eventually rectangular ones became popular in the mid-1830’s. Some materials for later frames included brass, tortoiseshell from the hawksbill turtle, baleen, steel, silver, and gold. The cases also were often very finely crafted. The oldest existing spectacle case in the world was found in 1982 in Freiburg, Germany and it probably dates to the 14th century.

From the beginning, spectacles failed to remain in position and stay on. As noted during the 15th and 16th centuries, they were of the riveted type which was normally hand-held. These spectacles evolved into the type with a more comfortable arched bridge known as bow specs. Following this, the ultra-rare slit-bridge spectacles appeared with slits to give some added elasticity to the nose bridge. Then one piece wire (usually copper) frames with round lenses, better known as Nuremberg style nose spectacles, came into fashion, being mass-produced throughout the 17th century and until the early 19th century. Compounding the problem of stability, the first spectacles did not have side arms. This critical problem went unsolved for about 440 years until finally London optician Edward Scarlett (1677-1743) was credited with perfecting temple spectacles – those having short, stiff side pieces ending in a circular ring that pressed against the temples above the ears. This innovation facilitated the easy putting on and taking off of the glasses and didn’t interfere with a person’s long hair or wig. It hasn’t been proven that Scarlett truly was the inventor. He advertised spectacles with spiral ends and his trade card is the earliest surviving illustration of them. Twenty-five years later, longer sides (temples) hinged in the middle became popular. This change finally added much needed comfort and stability. Another London instrument-maker and optician, James Ayscough, gets the credit for inventing this first double-hinged temple in 1752. He described these sides as "so contrived as to press neither upon the nose nor upon the temples." 3 In 1783, Optician Addison Smith obtained the first spectacle patent, # 1359, in London for two additional lenses hinged above the distance correction and capable of being rotated down for close work (making a total of four lenses). In 1797, English Optician John Richardson conceived the idea of different four lens spectacles where the two supplementary lenses, patent #2187, could be rotated in when doing close work. That same year, English optician Dudley Adams patented a device with a near complete headband and folding, adjustable drop-down lenses. No part of the spectacles rested on the nose and the distance between the two lenses could be modified depending upon the interpupillary distance. Only a half dozen of these super orbital patent specs are known to exist in private collections today.

In England, especially between 1758 and about 1790, the so-called Martin’s Margins became popular. London optician Benjamin Martin (1704-1782) developed these Visual Glasses in 1756 in an attempt to reduce the supposed damage to the eyes from excessive light. The aperture of the lenses was reduced by a horn annulus placed inside the ordinary sized frame. They were described in his "Essay on Visual Glasses (Vulgarly called Spectacles)" and then remained popular during the Revolutionary War period. Martin felt that these smaller sized lenses were beneficial for the eyesight. Interest in them, however, faded after the turn of the 19th century.

Bifocals or split lenses were improvised most likely in London after the 1760’s by Benjamin Franklin (1706-1790). They were made by halving lenses of differing powers and positioning the segments together with a straight line across the middle. The upper portion was ground for distance vision while the lower portion was ground for the near vision. He was certainly wearing them and able to order them from local opticians by the mid 1780’s. Franklin wrote to London philanthropist George Whatley in May 1785, "as I wear my own glasses constantly, I have only to move my eyes up or down, as I want to see distinctly far or near, the proper glasses being always ready." Franklin’s split lens bifocal was the first "no-jump" bifocal, one hundred years ahead of its time, because the distant optical center, the near optical center, and the combined optical center were all at the same point.

During this period, spectacles also came into more common use in the United States. John McAllister, Sr. (1753-1830) arrived in America from Glasgow, Scotland in 1775 just before the Revolutionary War. He began selling hickory walking sticks (canes) in 1783 and, soon thereafter, riding whips. In 1799, he decided that spectacles might be an appropriate addition to these other wares so he established the first optical shop in America in Philadelphia. Until the War of 1812, McAllister imported all of the spectacles he sold in his shop. However, as a result of the conflict, the major trade embargo with Great Britain forced all Americans to rethink their dependence on imported goods. McAllister, a perfectionist, began producing his own gold and silver frames in 1815. Astigmatic lenses came into being in the U.S. in 1828 when McAllister and his son John, Jr. began importing cylindrical lenses for the correction of astigmatism. Actually Sir George Airy (1801-1892) was the first to design concave astigmatic lenses for his own myopic astigmatic eyes in 1825. John McAllister, Jr.. (1786-1877) also has the distinction of developing the system of numbering street houses by blocks of 100 – 200, etc. with even numbers on one side and odd numbers on the other. This was first adopted in Philadelphia in 1858, and then spread throughout the United States and to much of the world. The McAllister family business continued for five generations over a span of 173 years and it developed from prolific spectacle making to optometry. Because of this remarkable family, Philadelphia ranks not only as the birthplace of the nation, but also as the focal point for the development of optometry. Basically John McAllister Sr. is undisputedly the first important figure in America’s optical field and the founder of the profession of opticianry in this country. 

Besides McAllister, there are over three hundred different maker and retailer marks found on American spectacle frames of the 1820’s -1830’s. Most certainly finding an original pin-in-slot example (the 1st adjustable spectacle sidearm introduced just after 1800) with a McAllister or any other maker’s mark in fine condition can be a rewarding experience for the collector. Following McAllister’s success, spectacle production continued to develop rapidly in the United States. In 1826, Optician William Beecher established a jewelry-optical manufacturing shop in Southbridge, Mass. By 1833 his workmen also began manufacturing spectacles to compete with the more costly foreign imports. He sold his business to Holdridge Ammidown and then in 1849 Robert Cole joined the company. Two years later Beecher bought back in and then in 1852, Hiram Wells joined the firm. His younger brother George Wells gained employment in 1864. All the partner’s interests were consolidated and, though the foundation of the company was in 1833, the American Optical Company was formally incorporated in 1869. In another important development, Optician John Jacob Bausch set up a tiny optical goods shop in Rochester, New York in 1853. Shortly thereafter, he needed some additional capital so he borrowed $60 from his good friend Henry Lomb and a partnership was formed. After the Civil War demand for their hard rubber ("Vulcanite") eyeglass frames increased dramatically and this company diversified its product line into precision optical products like microscopes, telescopes, binoculars, and photographic lenses. Thus began a long growth period for both of these companies whose purpose was to make a profit from products that would improve man’s priceless faculty – eyesight. American Optical and Bausch & Lomb became enormously successful up to the end of the 20th century. Their influence even continues into the 21st century.

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