Chemical and pharmaceutical products.
As we entered this room, a visitor, a worker who had preceded us, said to his wife: "This is the box of tricks, you see; you have to know it, but for a connoisseur there is nothing more beautiful in the Exhibition. "
This visitor was right.
Small cupboards of a uniform style run all around the gallery; a double row of cupboards leaning against each other and in all respects similar to the previous ones occupy the axis in its entire length. Jars, flasks, cups and samples of varying sizes fill them. If one approaches, one reads on the labels names that are difficult to spell, hard to pronounce, and which an unexercised memory retains poorly and even does not connect at all. It is not that there is a lack of objects here which by the brightness of their colours or the purity of their forms make a pleasant impression on the eye. It is nevertheless true that at first sight this does not say much to the layman. Each of these substances is an enigma, and the key that explains it is a whole science. But if the initiated are rare, the believers are numerous, and there is no one who, on crossing the threshold of this gallery, does not know that he is entering the domain of a science which takes an incomparable part in the work of progress and whose benefits are such that among its most vulgar gifts there are some which could not be lacking without almost all industry coming to a halt.
Such is, for example, sulphur, or rather the product of one of its combinations with oxygen, i.e. :
Without it, there would be no soaps, no crystals, no candles. All we would have left to light us is an impure, smoky, nauseating oil. We would have to look for new ways to bleach cotton fabrics. A large number of colours and mordants used to dye them and make the dye indissoluble, would also be lacking. We would no longer have the alcohol extracted from grains and potatoes, nor the chemical matches, nor the many mineral and organic acids used to prepare medicinal substances. And this is only a part of the services we derive from it. So important is it that the degree of industrial development of a people can be measured by the amount of sulphuric acid they consume.
It is therefore not surprising to see the number of French exhibitors who are dedicated to the manufacture of this precious product.
Among the number, we should mention MM. Kuhlmann et Cie, owners of chemical product factories in Loos, la Magdeleine, Saint-André (Nord), Corbehem (Pas-de-Calais) and Saint Roch lès-Asnières (Somme), which deliver to the trade more than 5 million kilograms of sulphuric acid per year; the Compagnie des salines et des produits chimiques de Dièuze, whose production reaches 8 million kilograms; and the Compagnie de Chauny (Aisne), from which 18 million kilograms are produced each year.
To give an idea of the importance of these large establishments, we will add that the latter Company also produces: 13 million kilograms of hydrochloric acid, 11 million 500,000 kilograms of sodium sulphate, 13 million kilograms of soda ash, 4 million 500,000 kilograms of soda crystals, 3 million 500,000 kilograms of soda ash and 3 million kilograms of chloride of lime!
Finally, one will get an idea of the business movement to which this production gives rise, when one knows that the Compagnie de Chauny consumes annually: 23 million kilograms of earth coal; salt, 10 million; chalk, 9 million; sulphur, 5 million; manganese, 3 million; lime, 1 million 700,000 kilograms; nitrate of soda, 250,000 kilograms
All that has just been said about the importance of sulphuric acid should be repeated with regard to nitric acid. I will limit myself to noting a considerable progress in the manufacture of the latter. The enormous quantity of sodium bisulphate produced by this process is now almost completely utilised. This residue, which was an embarrassment, has become a treasure; when it is involved, chemistry goes beyond the kitchen, it leads in the art of using leftovers.
Among the samples of chemically pure metals shown at the Exhibition, samples of incomparable beauty, our attention is drawn to the thallium ingots that M. Lamy, professor at the Lille Faculty of Sciences, places before our eyes.
Thallium is one of the metals whose existence has been revealed by that marvellous and recent method of chemical investigation which has received the name of spectral analysis. The discovery of caesium and rubinium have the same origin.
It is known that a large number of metals introduced into a flame in the form of volatile compounds, cause lines of various colours to appear in the spectrum of this flame, each of which always occupies a specific position. An English chemist, Mr. W. Crookes, studying with a spectroscope a flame into which had been introduced a small portion of the deposits which are formed in sulphuric acid factories, found in it a green line, which did not belong to any known body, and after many trials he became convinced that this line was due to a new body, to which the name of thallium was given.
The study of thallium was the object of the persevering studies of M. Lamy, and it is to him especially that we owe the knowledge of the properties of the new metal.
As can be seen, thallium is similar to lead and silver in its properties. It is very soft, very malleable, can be scratched by the nail and easily cut with a knife. Its density is a little higher than that of lead; it melts at 290 degrees. The discovery of this body somewhat disturbs the classifications of metallic bodies. Thallium, in fact, does not naturally belong to any of these, and the combination of the apparently paradoxical characteristics that it presents has led M. Dumas to give it the picturesque name of "platypus of metals". So far it has no use in the arts; but how many bodies of unparalleled importance today have, like this one, begun by being good for nothing!
The products of coal tar.
Where the powers of chemistry shine forth above all is in the incomparable products it has been able to extract from coal.
The sludge distilled in closed vessels gives gases, ammoniacal salts and a crude oil known as coal tar or coaltar.
This tar is a very complex compound. How from reaction to reaction picric acid and nitro-benzine are obtained from it; this would take us too far. Picric acid is used in dyeing; a skein of silk immersed in a small quantity of this acid takes on a very beautiful yellow colour without any preparation. A small apparatus, exhibited by Mr. J. Casthelaz, enables the purity of this product to be checked in a few minutes. As for nitro-benzine, it is the starting point of these brilliant colours which have so rightly excited general admiration. Nitro-benzine, suitably treated, gives rise to Y aniline, and it is from this that the colouring principles known as mauve, magenta, roseine, azuline, azaleine, fuchsine, Paris blue, etc. are derived. This beautiful industry allows us to note a progress similar to that which we noted in the manufacture of nitric acid; one knows today how to benefit from the considerable residues left by the successive transformations of benzine into nitro-benzine and aniline.
M.Eusèbe, of Paris, has grouped together in his showcase some beautiful samples of silk dyed with aniline green, a green whose discovery is due to a very singular chance. It is said that Mr. Eusèbe's foreman, wishing to fix a certain shade of blue on silk, had the strange idea of immersing the fabric in a bath of hyposulphite of soda; believing that he was fixing blue, it turns out that he had produced green.
Among the products derived from coal essences, let us mention a certain oil with a penetrating odour, discovered by M. Marignac, called formene binitré bicliloré, by M. Berlhelot, and of which we have a bottle before us. This oil irritates the eyes and respiratory tract to an inexpressible degree; the contents of this bottle, spread throughout the Palace, would be enough to make all the visitors who fill its immense galleries burst into tears.
Paraffin, of which we have such beautiful samples, is one of the products of the distillation of coal, of certain coals at least, of boghead among others.
When this boghead is distilled very slowly, an oil called o'éinc is obtained. This oil dissolves a substance which first appeared in the form of candles at the 1855 Exhibition: this is paraffin, which is in reality only solid olefying gas, and the beautiful white light given by the magnificent candles formed from it is the light of the olefying gas itself.
We will stop here, not without regret, this preliminary glance at the chemical industry, an industry which is always progressing and which today produces 1200 million per year, 53 of which are exported. In these showcases there are substances of admirable purity, of immense value; a small cup containing only a few grams of material contains a marvel. We would have liked to stop in front of all these things, but we lack space. Let us therefore confine ourselves for the moment to noting with the jury, among the progress made since the Exhibition of 1862, firstly the improvements made to aniline colours and the appreciable reduction in their price, then the acquisition of new colouring materials derived from toluidine and metylaniline, then the transformation of naphthaline into benzoic acid, and finally the industrial production of magnesium. And let's go to the next room where we will find ourselves in the middle of :
Products of Mining and Metallurgy.
And first of all, as a natural introduction to the history of this class, a showcase containing the collection of rocks, minerals and ores extracted from our soil is displayed. It is on display by the Ministry of Agriculture, Trade and Public Works. Above the cabinet, on the left, is a large map of France, showing the coal basins, the earth ore mines, the deposits of the main metals other than iron, the iron factories and the forest massifs within the supply radius of these factories. To the right and matching this map, another map of France, drawn to the same scale as the previous one, indicates the deposits of fossil lime phosphates, discovered by M. de Molon, the banks of tangue, merls, tress and shell sands, the deposits of felds-paths, potassic deposits, kaolin and the limestone deposits of the coast of the Channel and the Ocean. The part of the above-mentioned showcase which is below this map, contains a superb collection of lime phosphates, classified by department.
Completely neglected some twenty years ago, this amendment has become the object of important exploitations in France and especially in England.
In France, phosphate is used in its natural state and simply pulverised. In England, it is usually only used after being converted by the action of sulphuric acid into double acid phosphate, known as superphosphate. In the factories where this operation is carried out, at Deptford near Greenwich, for example, the mineral phosphate before being treated with acid is first mixed with a certain quantity of bone phosphate, and sometimes with earthy guano. There is still some doubt today as to the best method of preparing mineral lime phosphate, but everyone agrees on the value of this substance as an amendment.
Opposite the geological exhibition of the Ministry is, as it should be, the practical exhibition of our mining companies. Monte-bras brings its tin ores; Alais, its antimony ores; Monistrol (Allier) and Pontgihaud (Puy-de-Dôme), their silver lead ores; Villemagne (Hérault), its copper and lead ores; Servas (Gard), its asphalt; Saint-Nicolas (Meurthe), its salts; Brittany, its kaolins, etc.; and then the coals of Graissessac, Lens, Courrières, Portes. ...; the cokes, agglomerates and coals of the Aniche company; the petroleum extracted from the sands of the Bas-Rhin and the shales of the Ailier. The Société des Pétroles Français de Schwabwiller was the first company in France to extract natural oil.
In the showcase which contains the riches of which only the smallest part has just been enumerated, a narrow compartment occupied by MM. Baudouin frères, exhibits the means and products of the process of M. de Rostaing for the division of molten metals and particularly of cast iron. The cast iron arriving liquid on a disc animated by a speed of 2000 revolutions per minute, is divided into very fine globules of an excessively easy oxidation, which by suitable dosages can be usefully employed to produce steel materials, or to manufacture by the complete oxidation and by the calcination of the red oxides which find their use in painting. This process of division also applies to lead, zinc and finally to copper mattes which are partially desulphurised during granulation.
Pangibaud shows us a magnificent silver ingot worth 135,000 fr. MM. OEschger, Mesdach et Cie exhibit one of a lesser value; it is a cake of gold-bearing silver obtained by coupellation of silver-bearing lead, which weighs 212 k 200 and which is quoted at the price of 51,000 fr.; but their beautiful exhibition is recommended in many other respects. From the foundries and rolling mills of Blache-Saint-Vaast, which they direct, millions of kilograms are produced annually to be delivered to the trade and to the arsenals of the State: sheets of rolled red copper for boiler making, the lining of ships, the manufacture of war and hunting capsules; copper ingots for the melting of art bronzes and machine parts; sheets of zinc for the roofing of buildings; lead in brine, especially suitable for the manufacture of ceruse, minium, etc. One of the specialities of this great house is the manufacture of copper coin blanks for foreign countries, which are then minted in the mints, and we have here a coin bronze 9 metres long from which thousands have been cut.
Not far from there, MM. Cubain et Cie, of Verneuil (Eure) and M. Manche, of l'Aigle, exhibit very fine samples of rolled and drawn metals; in the display of the former, attention is mainly drawn to a sheet of copper 5 m. 40 c. long and 1 m. wide. 40 c. long and 1 m. 20 c. wide, and which weighs 32 kilograms; on a piece of rosette wire, clear, hard, which is 22 millimetres in diameter, 23 metres long and which weighs 75 kilograms, and finally, on a piece of clear, hard brass, which is 16 millimetres in diameter, 84 metres long, and which weighs 132 kilograms. Mr. Mouchel, next to objects of boilermaking made by repoussé, by means of the lathe, placed a fancy piece of brass wire of the size of 3 hundredths of a millimetre, which is finer than the hair. If it were not for the colour, these brass wires would be mistaken for real hair; even so, in the present day of hairpieces, this colour could become fashionable.
To a higher art is devoted the beautiful window of M. Godard, supplier of the war depots. We have here admirable copper, steel and zinc plates intended for engraving; a plate in extra-fine red copper, flattened and polished for intaglio engraving, is 1 metre by 1 metre 35 cents, and weighs 75 kilograms.
M. Dupré, inventor of metal caps for bottles and flasks; M. Massière, who manufactures tin foil; M. Guérin, tin beater; and M. M. M. M., who makes tin foil. Guérin, a gold beater, exhibit their interesting products in this first room, and we gradually move from industry to Fart, into which we are introduced to Vieille-Montagne, which shows us all that can be done with zinc, and the Sommevoire factory (Haute-Marne), which teaches us to what degree of relative perfection iron casting can be raised. These are interesting subjects of study on which we hope to expand in a future issue.
©L'Exposition Universelle de 1867 Illustrée