**Still life by Willem Claeszoon Heda, 1634. The artist placed the silver salt cellar in the exact centre of the picture.** Rijksmuseum Amsterdam

The salt of life

Salt is much more than just a seasoning. Salt is essential to life, and therefore a valuable commodity. For centuries Switzerland was dependent on salt imports. In 1836, a determined German drilling specialist and ‘salinist’ changed that for good.

Thomas Weibel

Thomas Weibel is a journalist and professor emeritus of media engineering.

If you work, you receive payment for your labour, a salary. ‘Salary’ comes from the French salaire, and that in turn goes back to the Latin salarium, the wages with which Roman legionaries were paid. Salami, salad, salary – all these words stem from the root word sal, which for thousands of years has meant ‘salt’ in numerous languages.

Without salt, there is no life. Table salt – more precisely, sodium chloride, with the chemical formula NaCl – is the most important mineral of all. 150 to 300 grams of salt circulate in an adult human body. Up to 20 grams of this salt is excreted daily, and it has to be replaced through our dietary intake. Meals can be seasoned with salt, and salt preserves meat, fish, cheese and vegetables. Salt has always played an important role in crafts and industry: in the tannery, the potter’s workshop, the pharmacy – and, thanks to chemistry, even in cooling. If you put beer bottles in a pot with water and ice cubes that you’ve sprinkled with salt, the beer cools down very quickly.

**Woman in front of a salt heap in Schweizerhalle, 1950.** ETH Library

In the Mediterranean region, on France’s Atlantic coast, in India and in Central America, salt production was straightforward in theory: seawater, which contains an average of 35 grams of salt per litre, was channelled into shallow basins called ‘salt gardens’ and after the water had evaporated, the salt crystals remaining were harvested. But not everyone lives on the coast. In inland areas, the options were either salt production from salt lakes, or mining of deposits of rock salt from prehistoric oceans; the salt was either quarried by mining activities or, alternatively, dissolved in water and evaporated in shallow pans. The term ‘cooking salt’, another name for table salt, comes from this process – not because we need the salt to cook, but because it was obtained by boiling. After extraction, the salt was filled in sacks, which were lighter than the usual barrels, and then transported over great distances, along the salt routes known as viae salariae. Salt was traded, stockpiled, taxed; people speculated with it and made political deals over it.

**Salt production through evaporation of seawater, from Georgius Agricola: De re metallica libri XII, 1566.** ETH Library

**Depiction of salt production in the Halle saltworks (Saxony-Anhalt), copperplate engraving, dating from around 1670.** Universitäts- und Landesbibliothek Sachsen-Anhalt

As a landlocked country, Switzerland was almost entirely dependent on salt imports until the 19th century. Salt from Tyrol and Bavaria supplied Graubünden and Eastern Switzerland; Bern’s salt mainly came from Burgundy; Geneva and Western Switzerland got their salt from the Camargue; and Ticino, Central Switzerland and the valley communities of southern Graubünden were supplied with Mediterranean salt from Venice to North Africa. In the Middle Ages, the salt trade was in principle unrestricted. However, because trading in salt called for international connections and a lot of capital, and because freedom of trade was restricted from the 16th century onwards, a kind of ‘salt nobility’ emerged in Switzerland. Hans Heinrich Lochmann (1538-1589) from Zurich and Benedikt Stokar (1516-1579) from Schaffhausen controlled imports from Savoy and the Camargue, while Hippolyte Rigaud (1558-1624) from Geneva as well as Michael Mageran from Valais (1575-1638) and Kaspar Stockalper vom Thurm (1609-1691) controlled those from Venice and France. The aristocratic Besenval family (17th/18th centuries) in Solothurn and François Fatio (1622-1704) in Geneva also amassed their wealth from the salt trade.

**Kaspar Stockalper vom Thurm from Brig, painting by his son-in-law Georges Christophe Manhaft, dating from 1672.** Wikimedia

**The salt mines of Bex, Canton of Vaud.** Wikimedia / Souvaroff

Despite the discovery of extensive salt deposits in Bex (Canton of Vaud) in the mid-16th century, Switzerland remained dependent on imports. That changed abruptly when, after years of failed attempts in the cantons of Bern, Valais, Solothurn, Zurich, Schaffhausen and Basel-Landschaft, German drilling specialist and ‘salinist’ Carl Christian Friedrich Glenck (1779-1845) struck it rich near Muttenz on 30 May 1836: at a depth of 135 metres, the drill bit hit a massive, 6-metre-thick stratum of rock salt. Entrepreneur that he was, Glenck established the Schweizerhalle saltworks, which commenced industrial mining activities a year later; within a short space of time, the company’s output increased to 10,000 tonnes a year. Salt was also discovered elsewhere; within just a decade, Schweizerhalle was facing competition from Kaiseraugst, Rheinfelden and Riburg (Canton of Aargau). Since 2014, the Swiss extraction sites at Riburg, Schweizerhalle and Bex, which are still active today, have been consolidated under the umbrella of Schweizer Salinen AG and, with around 200 employees, these sites produce 400,000 to 600,000 tonnes of salt annually.

**Drilling rig at the saltworks in Schweizerhalle. Photograph by Edith Bader-Rausser, before 1959.** Swiss National Museum

**The ‘Saldome 2’, the domed salt storage facility in Rheinfelden, completed in 2012.** Wikimedia / Brenneisen

Being the salt of the earth, oversalting someone’s soup (raining on someone’s parade), rubbing salt in a wound – salt is omnipresent in language and culture. Throughout history and prehistory, salt has been not only essential to life, but also precious, and as ‘white gold’ it has always had considerable symbolic significance. As a sign of prosperity, the omnipresent salt shaker has been an icon of painting in every era. In the Baroque era salt was even a symbol of purity and, because it is essential to life, of Christ himself; knocking over the salt shaker was considered a very bad omen. No salt, no life, no god: ‘That comes… from dreary atheism!’, Gottfried Keller has his character Green Henry exclaim in 1879, in the novel of the same name: ‘Where there is no god, there is no salt and no foothold!’