A Manual of Mending and Repairing; With Diagrams

by Charles Godfrey Leland

A great deal of mending and restoring in glass can be effected by means of the blow-pipe and spirit-lamp or gas-flame. Difficult as this may sound, it is not only an easy, but also a very curious and entertaining, occupation. In any city an expert or workman may be found who would give a few lessons. I have very often been impressed with the fact that so little artistic invention or originality is found in glass-work. Even the far-famed Venetian work is extremely limited, and “mannered” or conventional, compared to what it might be.

The following is an old recipe for repairing glass:—Take finest powdered glass, best mastic, with equal parts of white resin and distilled turpentine. Melt all well together. To use, gradually warm it and then apply.

Quicklime and white of egg, intimately rubbed into one another on a flat surface, make a good cement for ordinary glass or pottery.

The cement of gum-arabic is much stronger when made as follows:—Take gum-arabic and dissolve it in acetic acid (vinegar) instead of water. It must be melted in a hottish place, as it will in that case be much better. The finest quality of sheet-gelatine makes a transparent glue, invaluable where colour is to be avoided.

To mend a cracked Glass Bottle or Decanter.—Heat the bottle, pressing in the cork, till the hot air within expands the cracks, which must be at once filled with the liquid glass. Then, as the water-glass is driven in by the pressure of the outer air, as the bottle cools the cracks are closed.

You cannot well mend a broken looking-glass, but something can be done with the large pieces. Varnish or paste a piece of paper and lay it on the quicksilver. Then with an American glass-cutter, price one shilling, or a diamond-cutter, divide them into squares for small mirrors. Two of these of equal size can easily be converted into a folding kaleidoscope (not described by Brewster in his work on the Kaleidoscope). Lay the two pieces face to face, and paste over the whole, on the quicksilvered side, a piece of thin leather or muslin. When dry, with a penknife, cut a slit down between the two on three sides. It will then open and shut like a portfolio. This may serve as a travelling, looking or shaving glass, but it is very useful to designers of patterns. Place the glass upright on a table at a right angle, or more or less, and lay between the mirrors any object or a pattern, and you will see it multiplied from three to twelve times, according to the angle. Beautiful variations of designs can thus be made, ad infinitum. They may be used as reflectors, when placed behind a light.

Take such a piece of looking-glass and lay a piece of paper on the back, and then with an agate or ivory point write or draw on it, but not as hard as to break the silvering. Then turn it to the sun or a strong light, and let the reflection fall on a white surface. Though nothing be perceptible on the face of the mirror, the writing will appear in the reflection.

Glass is engraved as metal is etched; with this exception, that, instead of sulphuric or nitric acids, fluoric acid is used. Both glass and china can also be directly etched with a steel point, aided by emery powder; which latter art I have never seen described, but which I have successfully practised. It is fully set forth in my forthcoming work on “One Hundred Arts.”

Malleable glass, or at least that which does not break easily when let fall, is prepared by dipping the objects made from it, while quite hot, into oil. I conjecture that panes of window-glass thus prepared would not be broken by hail, as I have observed that plate-glass is not.

It sometimes happens that goblets of thin glass—especially those which have had a peculiar kind of annealing or tempering—ring beautifully when blown on so as to vibrate them. The effect is almost magical on one who hears it for the first time. I mention it that the reader may, when he finds old Venetian or any other thin glass goblets for sale, see if there be not among them a finely ringing one. An organ could be thus made to play by wind. With regard to music on glass, take any ordinary bottle, and by rubbing on it a cork a little wetted you can, with a little practice, produce a startling imitation of the chirping, and even warbling, of birds. I knew one who could thus imitate to perfection nightingales and call forth responsive songs. The effect depends in a degree on the quality of the cork, and also that of the glass. With a violin-bow very musical sounds may be drawn from the edge of a pane of glass. It seems as if these methods might also be developed into musical instruments. It is well known that tubes of glass suspended when a candle is placed beneath them give forth musical sounds, often of great richness and strength. There are also the musical glasses, which may be played in two ways, either by rubbing the edges with a wetted finger or by filling the glasses more or less with water till an octave is formed, and then tapping them with a stick of wood. All of which has, indeed, nothing to do with mending glass, yet which may not be without interest to those who wish to learn all its qualities.