Take a piece of fine stemware and examine it for flaws. Hold it up to the light. Look carefully at its shape and texture, its shine and clarity. Someone trained in the art of glassmaking will be able to detect slight imperfections and deformities, some so small and subtle as to be unnoticeable. A craftsman shares the same devotion to process and technique as an artist. After a lifetime of dedicated training and practice, years and years, you realize you’re just starting take notice of the more subtle, esoteric aspects of the art.
Fine glassmaking begins with the objective of the factory owner and the skill of the workers. The trade is best learned under the apprentice system in which a senior gaffer teaches his younger helper by demonstration…Engraving plays an important part in the design and decoration of Steuben glass, and, since this is a slow and tedious process, fewer and fewer young people enter the engraving trade. Only the apprentice system has enabled Steuben to overcome this bottleneck in production, a battle which is far from won. Glass, being transparent, shows any defects more obviously than any other product made. There is no such thing as a perfect piece of glass any more than there is a perfect fur coat; but there is constant supervision of the molten fluid to test for bubbles or seeds, resulting from imperfect mixing and melting, which could show up in the finished piece. If such defects do appear in the article, even after such precautions, it is broken and put back in the melting pot.[1]
Constant supervision of the molten fluid. You’re looking, you’re engaged, you’re searching, but small defects slip past. Why? Any number of reasons. Overestimating the validity, and solidity, of our evidence and proof. Not being detached, objective. Believing others will ignore the small imperfections, errors, and inconsistencies in the cases we present. (A hint: they won’t.) “Glass, being transparent, shows any defects more obviously than any other product made.” We need to constantly supervise and evaluate the molten fluid––while “slow and tedious” doing so is an essential part of the process.
Sand is the commercial representative of silica. The quality of glass is mainly determined by the quality of the sand used in its composition. The impurities generally present in sand are iron, lime, alumina, chalk, and magnesia. The quality of a sample of sand is estimated according to the quantity of iron contained by it. For common bottle-glass, sand is obtained in sufficient purity from the sea or river shores; for better qualities of glass, the sand is quarried as sandstone, and ground to powder. The purest sands at present in use in this country are obtained from quarries in the Forest of Fontainebleau, in France, and from Alum Bay, in the Isle of Wight…[2]
Selection of the purest ingredients. Selection of the purest ingredients, then the skill, devotion, and care with which these ingredients are mixed––the process should be reevaluated at each step to insure there are no flaws in the glass––an endeavor akin to any long, arduous physical and spiritual undertaking, as if the search itself were a pilgrimage to a sacred destination. Subtle gradations in the quality of the ingredients––small refinements, ignored by others, can lead to improved outcomes. Are you looking? Have you developed the ability to identify these small differences?
A good way of testing the quality, is to take a magnet and insert it among the sand, by that means the particles of iron will adhere to the magnet; you will then be enabled to judge the purity of the material; but a great deal may be done to make the sand pure by washing it well several times in fresh water, and then burn it in a sand arch (reverberating furnace) to a red heat; when it is cold, put it through a fine brass wire sieve. You cannot be too careful in keeping this as well as everything else that is used in the mixture of Glass particularly clean.[3]
Establishing a litmus test. A magnet, a thermometer, a digital PH meter––too often we do not have a single instrument with which to calibrate and measure. We submit our positions, stake our claims, without any preexisting reference point, gauge, or scale to guide us. What this means is we have to create our own litmus test, using the facts, data, and materials provided to us in any given case. There’s uncertainty, of course, but this uncertainty does not imply our work conforms to no set standard. “Purity of ingredients”––such a mindset is a good place to start––then to “put it through a fine brass wire sieve.”
In the mixing of Flint Glass, you cannot be too particular, both in the quality of materials and in keeping all dirt from amongst your Batch. It is necessary if you mean to keep your metal good, to keep it free from iron, so that it may keep its colour and brightness…When you make Batch Metal, fill your pot once full of the batch, and lade it as soon as it is melted down, which should be in ten or twelve hours, and then refill it with the remainder of your Batch and Ladings mixed. There is ten times more art in making good first-rate Flint Metal than there is in coloured Metal. It requires great care and watchfulness to be a good Metal Maker. [4]
Practice of care. Being engaged for a few minutes or hours differs from being engaged for months or years. The latter implicates a far greater time horizon––and we can’t see its outermost edge. Drift can take place if we don’t create our own markers, our own sight lines, set by no one other than ourselves. Hand blown glass, engraved by hand––the blowpipe no longer a piece of equipment, but an extension of spirit, transmitted to each piece with each breath. “Hence, tube blowing not only represents the initial attempts of experimentation by glassworkers at blowing glass, it is also a revolutionary step that induced a change in conception and a deep understanding of glass.”[5]
The best test for sand is examination with the microscope. Practically, pure sand should be perfectly white, and should not effervesce or change colour when heated with hydric chloride…Pure sand is insoluble in all acids, except hydric fluoride. For the manufacture of the finest glasses, the sand is subjected to the preliminary processes of washing, burning, and sifting. In the first, the sand, after being agitated with a large volume of water, is allowed to settle by gravitation, whilst the lighter particles of dirt, chalk, and other extraneous matter are removed in suspension, by withdrawing the water from above.[6]
Assume a knowledge deficit. You’ve been in practice many years. You know your field. You’ve had any number of successful outcomes. But for purposes of your next case a good rule of thumb is to assume a knowledge deficit. A good working assumption should be to assume you know only ten to fifteen percent of what’s required to be known for any given case. Such an assumption will force you to dig deeper, explore remotely, not take things for granted. Searching for flaws in the glass––when you hold it up to the light, what do you see? Sunlight shines down, enabling vision, making things clear.
[1] Stanley Marcus, Quest for the Best, Pg. 90-91 (Viking Press, 1979)
[2] Henry James Powell, Henry Chance, Henry Graham Harris, The Principles of Glass-Making, Pg. 24-25 (London: George Bell & Sons 1883)
https://books.google.com/books?hl=en&lr=&id=Qbs0AQAAMAAJ&oi=fnd&pg=PA1&dq=glassmaking+quality+&ots=fvi3sd51-I&sig=Wf5WIuiR_J5e5ak1COt3x37Y2xY#v=onepage&q= glassmaking%20quality&f=false
[3] William Gillinder, Treatise on the Art of Glass Making, Pg. 13 (S. Russell 1851)
https://books.google.com/books?id=fhldAAAAcAAJ&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false
[4] William Gillinder, Treatise on the Art of Glass Making, Pg. 51 (S. Russell 1851)
[5] Glassblowing/Wikipedia
[6] Henry James Powell, Henry Chance, Henry Graham Harris, The Principles of Glass-Making, Pg. 24-25 (London: George Bell & Sons 1883)
