The History of Windows.
THE origin of the word window is suggestive of the primary intention of that very essential feature in building. It is derived from the Welsh wyntdor, which means a passage for the wind; showing clearly that time first office of the window was ventilation, and not lighting, although it is used for both purposes in these latter days. Its early history is one of curious interest, now that plate-glass has assumed almost illimitable dimensions and surpassing beauty.
It is beyond all doubt that these apertures in buildings were, in early times, mostly filled with paper, in lien of glass, which in those dark ages was as yet unheard of. Even in this, our own enlightened day, one finds paper in use in some parts of Italy.
Authorities are at variance as to the discovery of glass, Pliny?s story being doubted in some quarters, though it is quite as probable as most of the fables by which the origin of many of the materials in common use is sought to be accounted for. Certain it is, however, that, though little may be known of the history of glass, its use for windows, as applied to building, is not of very remote date, as the antiquarian finds that, in very early times, the windows of Ainwick Castle,
the seat of the Duke of Northumberland, were great curiosities of art, as being glazed; and that, when time noble owner left home for a time, the windows were carefully removed and laid away in a dry, safe place, so precious were they reckoned in those days in England. Horn, prepared so as to make it as transparent as possible, and even oiled paper, were in common use in domestic buildings. The sacred edifice was the first structure in which window-glass made its appearance; and so inferior was the quality, judged by the present standard of excellence, that the meanest dwelling in America would not use such a material. In fact, there is no glass so inferior made, at this day, in the United States.
At first, windows were built in permanently with the structure; though time necessity for ventilation, at first compelling the hinging of certain sections of the frame, soon called for the hinging of time whole frame. Then as window openings were made wider, double frames were introduced, with a mullion in the middle for the windows to shut against. In the middle of the seventeenth century the lifting sashes were invented, and were soon found to be far better for protection against the weather. In fact, they began to be generally used; and, at this day, form parts of the most comfortable of all windows in vogue. The glass used in first-class houses, as well as stores, is made in Paris, and is always a double silicate of soda and lime. The soda in window-glass proceeds from a mixture of sulphate of soda and carbon. The process followed in the manufacture of such glass may be described.
When the glass is purified and skimmed off, the blower plunges repeatedly an iron blow-pipe into the melted silicate, and takes up a mass of considerable size. By blowing into the pipe he forms a spheroid, and at the same time gives a motion to the blow-pipe like that of a bell-clapper. The globe elongates considerably, both by its own weight and by time blowing. The blower then places the closed extremity of the elongated globe in the furnace, keeping his finger on the other end of the pipe. That part of the glass which is heated fuses, the air contained in the glass globe dilates and bursts it. He then turns it briskly, so as to enlarge the opening, splits it open by throwing some cold water on the end of the pipe, and proceeds to spread it out. He traces with water a straight line along the length f the cylinder, and then passes a red-hot iron over the wet mark; the cylinder splits in twain, and is carried to the oven to be spread out. As it heats, it opens, and soon forms a plate of glass; which is spread out by means of a plane of wet wood. The plate is then placed in the furnace for annealing.
Further information on the subject of plate-glass manufacture may be derived from a very useful translation from time works of Pelouze and Frkmy. To plate-glass the age owes the principal beauty of our modern stores, as its dimensions are so great as to obviate the necessity of the window-rails, which formerly crossed each other so often as to impede the entering of a full light and the perfect display of wares.
The formation of window-glass into segments of circles, ellipses, ogees, and the like, is a state of advancement which no doubt awaits the future history of windows.
- Taken from The Manufacturer and Builder Feb 1896