Instead of these valseuses two great plates of glass are now fixed side by side with plaster on huge tables, and two large ashlars are set turning by steam on their own axes while they describe a great orbit over the plates of glass. A stream of water constantly plays upon the plates, which are also constantly powdered with fine sand. The ashlars turn on their axes thirty or forty times a minute, and the plates of glass are usually smoothed and 'evened' on both faces now by these machines in from eight to nine hours, including the time spent in taking them out of the plaster after one face has been smoothed, and fixing them anew in the plaster, that the other face may fare as well. Here again a considerable economy of time has been made. And, after all, when one looks into the practical production of any of these great marvels of human industry, it is in this economy of time that the real advance of modern science beyond the results of ancient invention seems to consist. With all our nineteenth-century chorus of 'self-praising, self-admiring,' where should we be if certain—for the most part, uncertain and forgotten—men of genius had not invented the primordial processes which made art and civilisation possible? The workshop came first, and was the real marvel in the case of every great industry. To talk of the 'invention' of the steam-engine, for example, is an absurdity. The 'invention' was the engine, an invention as old as Egypt or China. The discovery that steam could be made to work the engine is the more modest modern achievement. In this industry of glass-making the amazing thing is that it should have come into the mind of a man so to apply the heat of burning wood to sands and silicates enclosed in an earthen vessel as to convert them into an entirely new substance possessing qualities not perceivable by any human sense in the sands, the silicates, or the earth.
What our modern progress in chemistry and in mechanics has enabled the makers of glass to do, is greatly to reduce the trouble and cost of producing this entirely new substance, greatly to improve the quality of the substance produced, and to extend the range of the uses to which it can be applied.
What would the Egyptians, who paid their tribute in glass to Rome, have thought of a serious order to pave the Via Sacra with blocks of purple glass? Yet such an order could be executed now at St.-Gobain, and when one sees the great flags weighing nine kilogrammes made here and used to let light into the cellarage below the carriage-ways, for example, of the huge Hôtel Continental, at Paris, it comes easily within the probabilities that the whole underworld of our great cities in time may thus come to be made available for divers uses, as so much of the underworld of Broadway now is in New York.
The great 'pavement question' is an open question still, in spite of asphalte and of wood, and there would seem to be nothing in the nature of things to prevent its being eventually solved by the glassworkers. The roofing question clearly belongs to them. The casting of glass for roofs began, I believe, with England, in the time of Sir Joseph Paxton, but it has been immensely developed at St.-Gobain. Over a hundred thousand square mètres of glass roofing made here were required for the building of the Exposition of this year at Paris. All the most important railway stations in France, from Nantes to Strasburg (unless the Germans have changed this), and from Calais to Marseilles, are thus roofed. In great warehouses, markets, public museums, street galleries—like those of Victor Emmanuel at Milan—factories, workshops all over France and the Continent, this conversion of the roof into a colossal window has revolutionised matters within the last twenty years. The light is making its way even into Turkey, where the great bazaar at Salonica has been roofed in glass by St.-Gobain, and as the Chinese, who, despite their early invention of glass, never got beyond using it for beads and little bottles, have condescended to admit great French mirrors into the Imperial Palace at Pekin, the glass roof may, ere long, make its way even into China.
In the form of tiles, such as are now made here, glass must inevitably, sooner or later, displace slates and shingles and terra-cotta for the roofs, even of private houses, it being quite certain that these glass tiles can be so used as to give a much better light in the garrets of private houses than can possibly be got through the windows. When that comes to pass the burglar's occupation of clambering stealthily from roof to roof will be seriously interfered with. What with glass roofs and glass floors and electricity, indeed, the city of the future is likely to be much more easily 'policed' and patrolled, as well as incomparably more cheery and habitable, than the city of to-day. Perhaps, too, when we all come to living in glass houses, the cause of peace and good neighbourhood may gain, and even Mrs. Grundy may grow more careful about looking into the affairs of her friends and acquaintances.
If that much maligned potentate the Emperor Nero had any real notion of the capabilities of glass when he established the first glassworks at Rome, the lamentation with which he took farewell of the world, 'qualis artifex pereo,' may have been inspired by regret at his not being allowed time enough to develop them. Certainly such gigantic mirrors as those which St.-Gobain has this year sent to the Exposition would have shown to better advantage in his colossal 'Golden House' than in any of our petty modern palaces. In what palace in England or in France to-day could a mirror measuring 7 mètres x 63 centimètres in height by 4 mètres x 12 centimètres in width, and thus displaying a surface of more than 30 square mètres, be placed, without dwarfing everything about it? These immense and magnificent mirrors must go hereafter to decorate palaces of public resort—'palaces of the people,' not palaces of princes. What was a royal luxury when Colbert wrote to D'Avaux in 1673 has become a popular attraction. The smallest restaurant in Paris would think itself discredited to-day were it decorated with one of the grandes glaces for which Colbert in 1693 thought St.-Gobain would find no purchaser save the king; but the Grand Café and the Hôtel Terminus of the Gare St.-Lazare order mirrors in 1889 which no king of our times would very well know what to do with.
Yet, once more, how the cost of these mirrors has fallen! In 1702 a plate-glass mirror showing two square mètres only by surface, cost, at St.-Gobain, 540 francs. In 1889 such a mirror, showing four square mètres of surface, costs, at St.-Gobain, 136 francs. A mirror showing ten square mètres of surface, which could not have been made in 1702 at any price, can now be had for 467 francs!
In 1802, under Napoleon, a mirror showing four square mètres of surface cost 3,644 francs, or very nearly three times the present cost of a mirror, not tinned like the mirrors of 1802, but silvered, of twice and a half that size. While new markets are constantly opening to this great industry all over the world, the progress of chemical science and of mechanics is as constantly suggesting new economies and new improvements in the manufacture of glass, and St.-Gobain, though one of the most thoroughly French of all French 'institutions,' shows no Chauvinism in its incessant study and prompt appropriation of these economies and these improvements. During the invasion of 1814 the workmen of St.-Gobain marched off to Chauny to resist the advance of the Prussians, and the manufactory had to pay a heavy fine for its patriotism. But it avails itself as readily of German as of French science to-day, and I found M. Henrivaux entirely and minutely familiar with the very latest phenomena of the great change which is coming over the glassworks, as well as all the other industries, of Pittsburg, through the use there of natural gas instead of coal gas and coal. All the most recently invented furnaces—English, German, American—have been tried and tested here as soon as they were made; and the latest American 'crushers' and 'regulators' get to St.-Gobain as soon as they do to Pittsburg. The materials which go to the making of a plate-glass mirror pass through seven processes before the original heap of pebbles, dust, and ashes is transformed into a sheet of splendour and light.
A hundred years ago more than ten days were required to complete these seven processes, from the crushing and mixing and putting into the furnace of the soda and the silicious sand and the charcoal and the lime and the broken glass, called here calcin, through the fusion, and the moulding, and the squaring, and the smoothing, and the washing, and the polishing. Now this is all done in half the time—127 hours instead of 246.
With all this the condition of the workmen employed at St.-Gobain has also steadily improved. It seems always to have been good, relatively to the general conditions of workmen in other industries and other establishments in France. Under the original statutes, and in the time of the excellent M. Deslandes, the nominee of Madame Geoffrin, who ruled St.-Gobain with great success from 1759 down to the Revolution, the workmen of St.-Gobain, as I have shown, were looked after, as well as kept to their duty, on strictly patriarchal principles, not likely to find favour in modern eyes. That they did not themselves dislike the system may be inferred from the fact that no such thing as a strike has ever been known at St.-Gobain, and that a considerable proportion of the workmen employed here now are the direct descendants of workmen employed here in the last century. There are even workers by inheritance, as men may be soldiers and sailors or magistrates by inheritance. Of course with the great extension in our own time of the operation of the company, great numbers of workmen other than glassworkers have come into its employment. But in the glass manufactures alone there are now employed: at St.-Gobain 375 workmen, at Chauny 583, at Cirey-sur-Vezouze 628, at Montluçon 473, at Stolberg, in Rhenish Prussia, 842, at Waldhof, in Baden-Baden, 518; making, in all, 3,419.