# Spectacles and Eyeglasses/Introduction

At what time man invented lenses and discovered the aid which they are capable of lending to vision is a matter beyond our knowledge. It is tolerably certain that they were known to civilizations earlier than ours. The late Wendell Phillips was wont to assert that spectacles were among the things known to the ancients. Though it might be difficult to sustain this assertion as regards spectacles in the present meaning of the term, the evidence in relation to their acquaintance with the essential element of spectacles, the lens, is reasonably convincing. This evidence was, for the most part, discovered by Sir Austen Henry Layard among the ruins of old Nineveh, and is of the most interesting character. Among the articles which he unearthed was a specimen of transparent glass (a small vase or bowl) with a cuneiform inscription fixing its date quite accurately to the latter part of the seventh century B. C. (“Discoveries Among the Ruins of Nineveh and Babylon, etc.,” by Austen H. Layard, New York, 1853, p.196.) This is the most ancient known specimen of transparent glass, though Egypt furnishes it of a date only a century later, and opaque or colored glass was manufactured at a much earlier period, some specimens of the fifteenth century B. C. still enduring. However, the ancient nations were not compelled to wait for transparent glass ​in order to invent lenses, as they had in rock crystal a material admirably adapted to that purpose, and Layard was so fortunate as to discover such a lens in Nineveh. (Ibid., p. 197.) Sir David Brewster, who examined this lens, described it as being plano-convex, of a diameter of one and a half inches, and capable of forming a tolerably distinct focus at a distance of four and a half inches from the plane side. It is interesting to note farther in regard to this, the oldest lens in existence, that it is fairly well polished, though somewhat uneven from the mode in which it was ground, which Brewster concludes was not upon a spherical surface, but by means of a lapidary's wheel, or some method equally rude. Another evidence of the use of lenses has come down to us from antiquity. Upon record-cylinders of old Nineveh, and on engraved gems and stones of Babylon, Egypt, and other sources which long antedate the Christian era, are characters and lines of such delicacy and minuteness as to be undecipherable without the aid of a magnifying lens. Taking these facts in conjunction, the statement that some of the properties of lenses were known to and utilized by the ancients, the old record writers of Assyria, for instance, may be regarded as almost as well demonstrated as though it were made of a modern engraver, and we were to step into his workshop and find his magnifying loup lying beside his work.
The testimony as to their use by the Romans during their supremacy is of a less conclusive character. The statement frequently made that the Emperor Nero used a concave jewel to assist his sight rests upon some obscure sentences in Pliny. That author says: “Nero could see nothing distinctly without winking and having it brought close to his eyes.” (Bk. II, Chap. 54, Riley’s Trans.) In another place, speaking of the emerald, smaragdus, he ​says: "In form these are mostly concave, so as to reunite the rays of light and the powers of vision. * * * When the surface of the smaragdus is flat, it reflects the image of objects in the same manner as a mirror. The Emperor Nero used to view the combats of gladiators upon (with, or by means of) a smaragdus.” (Bk. 37, Chap. 17.) The mention of the reflecting properties of the emerald immediately before the statement of Nero's use of it, with the alternative renderings of the Latin ablative, smaragdo, make the supposition that Nero used the emerald as an eyeglass uncertain, though in view of his clearly described nearsightedness, the conjecture is probable enough.
Lenses appear to have been unknown in Europe during the first twelve hundred years of the Christian era, though the Saracen Alhazen, who died in Cairo in 1038, has left books showing his acquaintance with them. These books were brought to Europe at a very early period, and the manuscripts yet exist, some in the Bodleian library, and another portion in that of the University of Leyden. It was probably from them that the early writers obtained their first hints of the science of optics, on the revival of learning in the fourteenth and fifteenth centuries. It is worthy of note that Alhazen was born at Bassora, at the head of the Persian Gulf and less than five hundred miles from the spot where, sixteen hundred years before, had stood the palace of the Assyrian kings in the ruins of which Sir Henry Layard found the lens of crystal. It might, perhaps, be plausibly maintained that in the countries about the Tigris some knowledge of optics, and of convex lenses, has persisted without eclipse from the most remote ages.
The earliest European reference to our subject occurs in the writings of Roger Bacon, who died in 1292, and to ​whom the invention of the instrument he describes is sometimes accredited. Bacon's glass was apparently a large plano-convex lens, probably what we now call a reading glass, intended to be held in the hand, and of it he says: "This instrument is useful to old men and to those that have weak eyes; for they may see the smallest letters sufficiently magnified." Spectacles proper—that is, glasses mounted so as to retain themselves upon the face—appear to have been invented in Florence somewhere between 1280 and the close of the thirteenth century. Dr. Samuel Johnson is said to have expressed surprise that the inventor of such useful articles has found no biographer. Doubtless among the thousands for whom the discovery has kept open the sources of knowledge there would be found one to pay this tribute to the fame of his benefactor were the identity of the latter a matter of certainty. But, unfortunately, our evidence on the point is of the most fragmentary character. We are told in a general way that the Chinese have for ages employed spectacles for the relief of defective eyesight. This is, perhaps, to be regarded as only another instance of the exercise of that claim to priority which the Chinese are known to extend over every good and perfect gift. The longest chase signally fails to bring the tradition to bay in any fact. The tomb of Salvinus Armatus, a Florentine nobleman who died in 1317, is said to bear an inscription to the effect that he was the inventor. If epitaphs enjoyed a less equivocal reputation for truthfulness he would doubtless be held in grateful remembrance as the man who has lengthened youth by postponing old age; and, like Joshua, kept back the night until the day's work was done.
Whoever the inventor, Alessandro di Spina, a monk of Florence who died in 1313, is generally accredited with ​having made public the use of spectacles, and by several Florentine writers of that time we find them mentioned and recommended. Pissazzo, in a manuscript written in 1299, says: “I find myself so pressed by age that I can neither read nor write without those glasses they call spectacles, lately invented, to the great advantage of poor old men when their sight grows weak." Friar Jordan, of Pisa, in 1305 says that "it is not twenty years since the art of making spectacles was found out, and is, indeed, one of the best and most necessary inventions in the world."
An early mention of spectacles, or, in the language of that time, “a spectacle," occurs in “The Canterbury Tales," where Chaucer makes the Wife of Bath use the metaphor:—
There is in existence in the church of Ogni Santi, Florence, an old fresco by Domenico Ghirlandajo, representing St. Jerome, and dated 1480. The Saint is portrayed seated at a desk, apparently deep in the composition of one of the blasts against the Heretics for which he was famous. Upon a peg at the side of the desk, together with the inkhorn and a pair of scissors, hangs a small handleless pince-nez. The glasses are round and framed in dark bone, and in the bridge, also of bone, is a hinge. Though the artist seems to have been little impressed by the fact that St. Jerome died in the year 420, nearly nine centuries before spectacles were invented, the mounting and material represented in these early spectacles are worthy of note as showing their form in Ghirlandajo’s time, and probably that in which they originated.
In the early references to spectacles it is the convex lens ​for the use of the presbyopic which is mentioned. Concave lenses were probably introduced soon afterward; by whom we do not know. Glasses were at that time and for long afterward selected and used empirically; since it was not until the year 1600 that the astronomer, Johann Kepler who may be regarded as the father of ophthalmology, made known in what manner the rays of light were refracted by the media of the eye and form an image upon the retina. Kepler went farther, and showed how convex and concave glasses influence this refraction, and to him is therefore due the honor of first scientifically treating this subject.
It must have been early discovered that there is a more or less close relation between the age of the wearer and the strength of the convex glass required, and the baneful theory was soon developed that this relation is constant, and that it would be ruinous to use a lens “too old for the eyes," a superstition from which the public is even yet not fully emancipated. We find it rampant in Pepys' time, preventing his oculist, Dr. Turberville, from giving that gentleman a proper correction for his accommodative asthenopia, of which the diary gives an accurate picture, and losing to the world many a priceless page. Pepys says (June 30, 1668): “My eyes bad, but not worse, only weary with working. * * * I am come that I am not able to read out a small letter, and yet my sight good, for the little while I can read, as ever it was, I think." But Dr. Turberville warns him against glasses too old for him, and so the diary is closed, and Pepys in a last pathetic entry resigns himself to coming blindness; and yet the ​convex lenses were at his hand, ready to dissipate the mists before him and enable him to "gaze upon a renovated world."
Improvement in spectacles appears to have been slow. The world waited more than two centuries after Kepler for another signal advance. Sir David Brewster is said to have discovered his own astigmatism; that is, he discovered that vertical and horizontal lines were not equally well seen by him at like distances, but the phenomenon was not explained and the observation faded from view. It remained for George Airy, the astronomer, to rediscover astigmatism, which he did about 1827, to determine that the curvature of the cornea was greater in one diameter than in another at right angles to the first, and to invent the cylindrical lens for the correction of the condition. Mr. Airy’s right eye was myopic, while in the left he had compound myopic astigmatism. By a careful comparison of the appearance of objects when viewed with each eye singly, and a study of the effect of concave lenses held before the left eye upon lines crossing each other at right angles, he was able to conclude that the refraction of that eye differed in different planes. Mr. Fuller, an optician of Ipswich, made, under Airy's direction, a concave sphero-cylindrical lens which satisfactorily corrected his refractive error. Thus was the last great discovery in spectacles accomplished,—a bit of work for completeness leaving nothing to be desired, and of not sufficiently acknowledged importance to humanity.
Benjamin Franklin invented bifocal spectacles. Since this statement is supposed by many to rest on tradition only, it may be of interest to quote a portion of a letter of Franklin's which bears upon the point. The letter is addressed to George Whately, of London, and is dated ​Passy, 23d May, 1785. In it Dr. Franklin says: “By Mr. Dolland's saying that my double spectacles can only serve particular eyes, I doubt he has not been rightly informed of their construction. I imagine it will be found pretty generally true that the same convexity of glass through which a man sees clearest and best at the distance proper for reading, is not the best for greater distances. I therefore had formerly two pairs of spectacles which I shifted occasionally, as in traveling I sometimes read, and often wanted to regard the prospects. Finding this change troublesome and not always sufficiently ready, I had the glasses cut and half of each kind associated in the same circle. By this means, as I wear my spectacles 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. This I find more particularly convenient since my being in France. * * *" (“The Complete Works of Benjamin Franklin.” Ed. by John Bigelow, New York, 1888.)
We may infer from the context that the invention took place before Franklin went to France, which was in the latter part of 1776. As he was born in 1706, the necessity for a double glass would first arise about 1750, and the invention therefore took place somewhere between this date and that of the journey to France.
The frames in which spectacles were mounted continued to be very clumsy affairs until the beginning of this century, when light metal frames were introduced in place of the earlier devices of bone, horn, or shell. Their later evolution has generally been along the lines of improved mechanical construction and increased lightness and beauty. It would be difficult to mention an article which plays a more important part in modern life than do spectacles, or ​one which plays its part more acceptably. It is scarcely possible to estimate them at their true worth, or to imagine our condition without them. Deprived of their aid, most men would be too old for work at fifty, and purblind at sixty. For us all, as an old writer quaintly observes, "they keep the curtain from falling until the play has come to an end."