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The New Zealand Railways Magazine, Volume 15, Issue 1 (April 1, 1940)

Buy … New Zealand Goods and Build New Zealand — New Zealand Industries Series — No. 14. Glass

page 9

BuyNew Zealand Goods and Build New Zealand
New Zealand Industries Series
No. 14. Glass.

At the New York World Fair there was a transparent motorcar, of which the fenders, hood, and body panels were all of glass. This was an ultra-modern development of the slogan of the glass industry, “See What You Buy!”

It is quite impossible to imagine twentieth century civilisation without this “hard, brittle, transparent substance, compound of silica and an alkali” as the dictionary explains.

But away beyond its utilitarian values for housewife and packer, glass has been one of the beauty-bringers to mankind, and its path of shining glory winds through our history for thousands of years. In the many temples of the arts, and I include in these the New Zealand Centennial Exhibition, folks stand entranced before exquisite examples of craftsmanship in glass. There are exquisite specimens dating back at least two thousand six hundred years, and even in Roman times, the accepted legend gave the Phoenicians the credit for the first glass receptacles. Egyptian tombs held glass amphorae with delicate and intricate designs in colour, and many of us know Waterford glass, with its crystalline brilliancy, and the charm of Bohemian, Muranese, and Venetian ware.

Few of us know, however, that New Zealanders have created notable examples of stained-glass windows, etched, and sandblasted glass panels, and that we make a wide range of glass containers, from the tiny one-ounce medicine bottle to the fullblown quart bottle of good cheer.

Stained-glass windows at Smith & Smith, Ltd., Wellington.

Stained-glass windows at Smith & Smith, Ltd., Wellington.

By O. N. Gillespie

(Rly. Publicity photos.)

I Remember, some years ago, standing on a green height of the North Auckland peninsula, and watching a white-winged scow passing deep-set in the blue water. “That's loaded with North Cape sand for the Auckland Glass Works,” someone said. I little thought that one day I would see that glittering freight piled up in miniature mountains in the storage shed of a company that was daily turning it into thousands of bottles.

This fine white sand is the ideal medium for glass-making, and constitutes, of course, the main raw material for this industry. The Auckland Glass Company is one of the largest of the great factory plants that line the wide Great South Road out of Auckland, and it keeps well over 300 New Zealanders in work, a substantial proportion of them heads of families. The equipment is the last word in modernity, and the daily output enormous. I found that the first process in the making of glass was mixing. Glass is really a silicate, and a number of other substances are used with the original sand and alkali to get various degrees of colour, ranges of tint, and types of composition. Potash, iron oxide, alumina, soda, lime and other ingredients are weighed with precision on automatic machines, and the conveying to the furnace is managed by a gigantic hopper installation. I noticed also that an ingenious travelling hopper system, devised on the spot, managed the movement of the materials, thus saving much carrying on human backs.

The compound, when finally settled, is fed into a mammoth furnace. One of the serious problems in a glass factory is to get materials sufficiently heatresisting for the walls of this sizeable volcano which maintains a temperature of no less than 2,665 degrees Fahrenheit. A peep through the door into the glowing, coruscating mass is an awe-inspiring sight.

The Auckland Glass Company makes the whole range of bottles from the poison container of opaque pleated blue to the wide-mouthed jam-jar, from the tiny, neat one-ounce medicine bottle to the brown-tinged familiar container for a quart of good cheer. There will be no war famine in “empties” this time, for this great Auckland establishment works at high speed. One-ounce medicine bottles pour out of one machine at the rate of 50 every minute.

The actual making of glass bottles is performed to-day by a collection of uncanny, complicated machines, armed with countless devices which operate with more than human precision, but seem somehow to have their own uncanny intelligence. Long ago, a bottle was “blown” from the end of a tube, as many of us will remember from those exciting visits we made to the tents of glass-blowers at shows.

The demands of mass production have altogether altered the technique. The glass, in molten liquid form, glides down by gravitation, and pours into moulds. These are on circular turntables which go endlessly round, a notch at a time. At a given point, the mould turns upside down, and air is blown in at the precise pressure needful to line the wall of the mould with a coating of glass of the requisite thickness. A plunger makes the hole at the top.

Then another turntable comes into action, the mould rights itself, and finally the bottle sets off on a conveyer track to the annealing furnaces. These are tremendously long ovens of the tunnel variety. “Lehr” is the technical term, and the bottles as they travel on the long conveyer pass through a slowlyrising and then a slowly-falling temperature. I should mention that, as is natural in an age-old industry such as this, there is a distinctive language. For instance, page 10
Bottles emerging from machine at Auckland Glass Company.

Bottles emerging from machine at Auckland Glass Company.

the sounding word “parison” is used for the “blob” of glass which will eventually become a bottle, and which once adorned the end of the blowing tube.

The temperature is an important question in glass-making, and the shine on certain vessels is got by the skilful use of varying heats.

Jam-jars, with their wide orifices, are made in precisely the same way, and everywhere there is the same feeling of automatic fingers, and sagacious wheels, all moving with the wizardry of mechanical workmanship.

Colour in glass, of course, is a matter of certain chemical ingredients, and I watched the blue poison-bottle materials flooding into their fluted moulds. Naturally, in a factory of the imposing size of the Auckland Glass Company, the army of moulds of various sizes and shapes is immense, but the general principle of bottle-making is the same throughout all variations.

By the way, the natural colour of glass carries, in its transparency, a faint green tinge.

A week could be spent in this forest of giant machines, but there is a limit to any layman's capacity for absorbing explanations of what these superhuman mechanisms are actually doing. The interminable storehouse streets of newly-made bottles are the witnesses to the efficiency of this New Zealand factory and the magnitude of its daily output.

A last surprise awaited us. This was the packing department. The Auckland Glass Company has its own complete plant for making the familiar corrugated cardboard containers. Machines, with heavy creasing rollers, take care of long sheets of this material, and groove it ready for bending at the right angles. The output is not confined to the familiar nests for bottles, for this company makes all the containers for the whole apple crop of New Zealand. Here, also, I saw the three-wheeled Scammel truck which turns in a ridiculously confined space. One of its uses is to convey the rejected bottles for re-melting. The most rigorous tests are constantly in use for flaws, water-marks, and any tiny fault. The smallest blemish means that the reject finds its way back to the furnace to join the molten river again.

The big staff of the Auckland Glass Company is predominantly male, and last year no fewer than four of its members were in the Rugby League touring
Rotary bottle-making machine at Auckland Glass Company.

Rotary bottle-making machine at Auckland Glass Company.

team that went abroad, which must be a record for one company. This company is a national institution and a cause for just national pride.

The uses of glass are increasing in the world of to-day, and we are promised all-glass houses, roads and countless other things. I was amazed to find the great number of New Zealand secondary industries occupied in making articles from glass. I was astonished to find that New Zealand had a host of craftsmen dealing in the modern applications of glass, both on the utilitarian and decorative sides of our lives.

I have stood with crowds admiring the ancient loveliness of glass garlands, coloured tapestries and gay rosettes of jewels all fashioned from glass, and other manifestations of wonder in vase and bowl and chalice. Mark Twain said, in the way usual with him which conceals a serious meaning under a laughing screen, that he reckoned the students, copying the Old Masters were improving on the originals. Thus I agreed, when looking at the displays in two Wellington city shops, that modern glass-work with its pure simplicity of design, its fine line and delicate colours, and its grace and symmetry, is somehow more satisfying to our eyes. I did not know, however, that these art objects were conceived by New Zealand artists and fashioned by New Zealand craftsmen.

The first example I shall use is the mirror. No household article of decoration has changed in fashion as much as the mirror.

I visited the Wanganui Glass Company's premises first, for I am always pleased to find a flourishing industry in a provincial centre like that pleasant river city.

The making of a mirror under modern page 11
Mouth of oil furnace (over 2,500 degrees Fahr.) at Auckland Glass Company.

Mouth of oil furnace (over 2,500 degrees Fahr.) at Auckland Glass Company.

methods is a fascinating thing to watch. The first necessity is distilled water, for the cleansing of surfaces for mirror-making has to be pluperfect. There are two processes, hot and cold, and, of course, there was the old-fashioned use of mercury—abandoned because of its danger to the health of workers.

New Zealand uses the hot method; the silvering bench is a cloth-covered large slab, maintained by steam heat at a fixed temperature. The glass is first treated with a thin solution of tin chloride, and then again with liquid silver nitrate and precipitate. This trio, together with the warmth generated by the table itself, produces the fixation of the mirror surface behind the glass. As the glass lies flat on the table, the deep film of liquid can be easily seen.

To keep it absolutely level, the operator skilfully fixes tiny wedges, and, as we watch, the surface goes black, and slowly returns to dull white. Carefully turned over, the glass shows the mirror shining clear. Backing of a shellac varnish is put on first, and then a paint. At a temperature of between 70 and 80 degrees F., a mirror is made in twenty minutes. The old-time cold process took three or four days. There is endless polishing with felt pads and chamois leathers, and the experts who do this work handle everything with scientific precision and meticulous care.

I also looked through the mirror-making plant of Smith & Smith's in Wellington. This firm was established in 1870, has four factories in New Zealand, and a long heritage of experience of local needs.

We all remember the plain mirror with its wooden frame, usually square, but now and again breaking into the impressive originality of oval or oblong. To-day the frameless mirror riots in a bewildering variety of design, of bevel, and mitre and embossed ornament, and lends lustre and dignity to any room.

I found at both establishments visited, modern production plants for converting the plain sheets of glass into this multitude of beautiful things.

First of all, the preliminary steps fall into four; the rough bevelling is done with a cast-iron wheel with carborundum edges; then the powdery edge, rather rough and milk white in colour is smoothed by a special stone “fine flow” spinning wheel; then, a still finer grain stone is used (coming only from Edinburgh), and finally disc wheels of willow wood carrying polishing powder are set to work. Willow is the only wholly satisfactory timber because of its softness and absorbent qualities. The final touches are given by rouge, and both at Wanganui and Wellington rouge is much in evidence.

Sand-washer at work at Auckland Glass Company.

Sand-washer at work at Auckland Glass Company.

The cutting of mitres and deep bevels is done by upright wheels of many types, and, of course, the element of personal skill enters largely.

At Wanganui, for instance, there is an émigré craftsman who does miracles of artistry in intaglio work, embossing, and other ornamental work of high aesthetic value. In the words of Smith & Smith's manager, also, “we can do, in New Zealand, anything at all in glass.”

The layman is familiar with the delicate grace of white cameo-like designs in modern windows, doors and panels. These are done by the new sand-blast process. The impact of the sand works at the back of the glass, and any effect can be got from filagree arabesques to masses of cloud effects.

Obviously the depth of the routingout can be varied infinitely by the sandblast method, and fairy-like nuances of line and shadow produced.

Modernistic design suits glass work. By means of colouring at the back of the glass, lovely effects are got, and there is no limit to the play of an artist's fancy. I saw in the display at a Manners Street shop, a noble picture in glass of Hobson and a Maori chieftain, a jewel-like bluebird flying across the top of a leadlight mirror apparently part of the glass scene, and at Smith & Smith's I saw feminine figures of entrancing perfection apparently swimming through the glass in silhouette.

The harmonious perfection of the panels and doors of the Wellington Railway Station is the work of the Wanganui Glass Company, and the list could be extended indefinitely.

Etching is also a process that has added to the possibilities of art work in glass. I found also that leadlight production was in a high state of development page 12 page 13 in New Zealand. The machines for bending the lead are the last word, and copper edgings are also used because of their superior rigidity.

The coloured glass is cut to suit the designs which are drawn in pattern books, and I did not realise how many widely differing kinds of glass existed until I saw the serried rows of samples at Wanganui. The vast store-room at Smith & Smith's is another sight of educational value.

These planned and progressive institutions make it possible to claim that in the use of glass for harmonising and enriching the beauty of our homes and buildings, New Zealand is not lagging behind world movements.

The crowning glory of glass art work is the stained window. It will be news to many readers that fine stained-glass windows are designed and fabricated in New Zealand. There is no need any more to import these precious additions to the dignity and charm of our sacred or secular public buildings.

The processes are most intricate. The stained-glass window is a painting in and not on glass. The pigments are fused into the very substance of the glass itself, and are kiln baked. Noble effects are got by the uses of depths in the etchings. Often times, as in the case of a serene saint's face, or slender blessing hands, the etching is on one side and the pigment on the other. Often, the pigment is on both sides of the glass. Antique glass has to be used for much of the composition of background and surroundings, because of its surpassing depth of colour. The artificer is aware all the time that the colours have to permit of light transfusing them. Smith & Smith's have contributed much to the beauty of windows in New Zealand. At the Maori Memorial Church at Kara-kura on the East Coast, there is a three-light window which is worth a special journey to see. It is an allegorical representation of the Western Front with the Crucifixion in the background. The Maori soldiers in the foreground were beloved lads of the district and their lineaments have been caught with photographic reality. Maori mats with their traditional meanings of history have been expressed in glass with exact fidelity, and the well-known Good Samaritan window at St. John's Presbyterian Church, Wellington, is a monument to the artistic craftsmanship of New Zealanders in this difficult medium.

I do not recall any journey through industry in my year's steady pilgrimage, that gave me more pride than this series of visits to the places engaged in glass-work. Beauty and usefulness join hands here in helping New Zealand's destiny towards a fuller and lovelier life.

Grave glass-work at Wanganui Glass Company.

Grave glass-work at Wanganui Glass Company.

Surface polishing, Wanganui Glass Company.

Surface polishing, Wanganui Glass Company.

Silvering mirrors at Smith & Smith, Ltd., Wellington.

Silvering mirrors at Smith & Smith, Ltd., Wellington.