THE manufacture of glass is of the first interest among the useful and ornamental arts. The art is one of the oldest which has been handed down from ancient to modern civilizations, and the collections in the Museum illustrate the history of the manufacture of glass with scarcely an interruption, from the invention of the art down to our own day.
It always has been an open question who invented this manufacture. Flavius Josephus ascribes the discovery of glass to the Jews, as the result of a forest conflagration when with the assistance of the sand in the soil glass came into existence. The Egyptians knew its making 4000 B. c., as may be seen in wall-reliefs of that time in which glass-blowers at work are pictured. The Chinese knew it of ancient times, and with the poetry of the East believed it to be the solidified breath of the Sacred Dragon.
The process of glass making consists mainly in what is termed ” blowing.” The fluid ” mass,” or elements from which the glass is made, is gathered at one end of a long pipe, and forms into a bubble by blowing at the other end. The bubble of hot glass is commonly shaped by an iron mould, which opens like a box with a hinge, the breath of the blower pressing the glass against the inside of this mould. When cooled it is finished by grinding and polishing. Goblets and the like are made without a mould, the shell, foot and stem being worked separately. The stems of wine glasses are ” balluster ” stems, ” airtwist ” stems, ” cut ” stems, etc. Classification is easier by the stem than by the bowl, for stems have been found to be more closely allied to definite periods.
The oldest method of engraving glass is with the diamond point, whereby as much free artistry is shown as in work with the etching needle on copper. The method in general use, and brought to perfection in England and Bohemia is holding the glass against a rapidly revolving soft-iron wheel impregnated with diamond dust and oil. In later years hydrofluoric acid has been used to grave on inferior glass. The Byzantine artists added enamelling and gilding to the modes of decoration known before their time.
A large and superb series of ancient glass may be studied here. There is Phoenician glass of unique form in yellow and blue colours, and unguent vessels from the 8th century B. C.; some ancient glass found in the vicinity of Tyre; a blue glass bottle from Egypt; and an unguent vessel of alabastron, from Memphis, Egypt, of about 600 B. C., decorated with festoons in various colours. We proceed further with a late Imperial Roman Cinerary Urn, of black glass with varicoloured bowl. Persian glasses with graceful necks, Saracenic glassware, Byzantine coloured glass bottles, a Vallencian water bottle with the arms of the Duke of Segorbia, and some other mediaeval examples bring us through this period to the magnificent product of the Venetian blowers. There is a beautiful selection of delicate and graceful work.. Specimens may be seen how in the 16th century the Venetians introduced threads of opaque white glass worked through the mass of the transparent substance. These vases are called vasi a ritorti if the threads go only in one direction, and vasi a reticuli if they cross each other. If different coloured glasses are introduced they are called millefiori. Specimens are here of the Murano products, when the Venetian furnaces were at the zenith of their fame. Also of that lost art to make the gilding of glass transparent only to be found in old Venetian glass. The gilding of today is always opaque.
The real Bohemian glass, which became world-famous, probably had its origin in the art of rock crystal cutting, imported from Italy. It soon became the rival of the productions of Venice. Its strong colours and bold outlines of decoration contrasted with the light lacework of the Venetians. It was very light, as the mass contained no lead. At the beginning of the 17th century the quality of Bohemian glass improved, becoming purer and whiter, owing to the substitution of potassium carbonate for sodium, carbonate in the manufacture. The form became more solid, more in keeping with the decoration it received, as shown in the Pokale (goblets) of the period. The light kind was blown, the more massive cast in wooden moulds.
The greatest artists in Germany were the Schwanhardts, father and son, who produced marvellously engraved specimens. About the middle of the 18th century large quantities of Doppelwandglasser snit Zwischen-Vergoldung were made. Ruby glass, coloured with copper or gold, was invented in the 17th century by a German named Kmeckel. It was revived in the late 18th century, but not with success.
Just as Bohemian had ousted Venetian, so in its turn it was eventually ruined by the English flint glass which, containing a large percentage of lead, has the power of decomposing light a property possessed neither by the former varieties nor by rock crystal itself. French, Russian and Spanish. glass present characteristic differences.
Little is shown of old American glass, although many bottles half a century old have interest and charm. Of these are the old golden, red, or brown-amber log-cabin bottles, barrel-bottles, the long amber ear-of-corn bottles, and the opalescent Bunker Hill Monument flasks. It is gratifying to note that the most wonderful product of the modern glassworker, the Favrile glass of Louis C. Tiffany, vies with the finest work of Venice or Bohemia. Objects, endless in variety of texture and colour, lustrous as the most brilliant opal, novel and classic in form have been produced as the result of almost twenty years of experimenting.
A distinct and beautiful branch of the art of glassmaking has been the creation of stained glass windows. The charm of the early mediaeval glass windows lies in the kaleidoscopic patterns, presenting, as it were, an illuminating wall mosaic. While the dark lines are unobtrusively introduced the aim has been to present brilliancy and harmony of the colour scheme. The earliest specimens of these windows were made of glasses the body of which was coloured, and not of glasses stained on the surface only, as was subsequently done.
The manufacture of stained glass felt strongly the influence of the Renaissance, and gained in beauty what it lost in strength and vigour. The invention of cutting glass with the diamond, of enamelling gold on glass, and important modifications in the working of lead, had also great influence on the work. After the Renaissance the art gradually declined, until of late, in France and England, modern products somewhat indicate a revival, which, however, scarcely may be considered to rival the beauty of the appropriate line and colour where-with the mediaeval artist sought to fill the open spaces. It is conceded that of modern work American opalescent glass, with its wonderful glow of colour and the depth of tone of which it is capable, can produce the finest results, exceeding in beauty and workmanship that of any other country.
Although no stained glass window of American artistry is at present in the Museum to demonstrate the personal development notable in opalescent glass, and the native individuality in this branch of art, there are on exhibition a few pieces of stained glass of great interest.
There are a couple of examples of the Nether-land school of 1500-1545; a Flemish window in the style of the mannered Brussels painters of 1530; a small Italian window, dating from the middle of the 16th century; a pair of French windows of the 17th century, representing the ” Annunciation “; three small German windows of the later 16th and 17th centuries; and two large German windows, painted, presumably, at Trier shortly after 1500, thereby forming a connecting link between the Mediaeval and Renaissance. The introduction of yellow tints in these German windows, which do not occur before the end of the 15th century, enables us to place their date. The figures represented are clear and distinct in design, simple and strong, and very decorative.
An example of a modern French window shows the pleasing and fantastic art of Luc-Oliver Merson, a master in this branch. It is called ” La Danse des Fiancailles,” and presents in luminous colours and a wealth of detail a picturesque scene of the epoch of the Renaissance, with dancers stately moving to the sound of strange instruments.