13. 5. 2025 | Aus Karlsbad, Geschichte
Desire for Knowledge
The Fates bestowed upon David Becher a strong desire for knowledge. However, we can also speak of his business acumen, considering the "thermal salt" affair, which unfortunately brought him only envy and hostility from fellow citizens. It mattered little that, thanks to him, the city treasury was filled with revenues from its sale, and that his discoveries helped Karlovy Vary develop into a spa jewel of Central Europe. Courage to follow one's own path, diligence, self-confidence, success—these are not easily forgiven.
David Becher left an indelible mark on the history of Karlovy Vary with his scientific treatises on the local springs. He published them gradually in 1766, 1772, and 1789. He examined the springs from the perspective of chemical composition and applied the results to patient treatment. He laid the foundations of modern spa therapy based on moderate drinking of mineral springs, pleasant baths, appropriate diet, and physical activity.
And what about the Karlovy Vary salt?
It was first mentioned by physician Stefan Strobelberger in his book on Karlovy Vary from 1629. Thermal water was poured into a large kettle, a fire was lit underneath, and once it evaporated, salt remained at the bottom. The production required a significant amount of wood, so the salt was produced only in limited quantities and sold exclusively in pharmacies.
A turning point came in 1732 when Saxon physician Nicolaus Borries visited Karlovy Vary and showed local dyer master Bernard Richter a method to extract mineral substances from thermal water. At that time, Emperor Charles VI was also staying at the spa, attended by court physician Carelli and the renowned professor Friedrich Hoffmann from Halle. When Richter presented the Karlovy Vary salt to them, their reaction was reportedly so favorable that shortly thereafter, Richter received a privilege authorizing him to produce and sell the Karlovy Vary salt. And thus it all began…
Like wasps, the citizens of Karlovy Vary swarmed around Richter, fearing that spa guests would stop coming to Karlovy Vary if they could establish spas at home. Through several complaints to the Prague governorate, they managed to have him prohibited from selling salt in whole pounds (0.3 kg) and allowed only in small packages of two lots (34 grams), which naturally meant a significant blow to his business. Tensions rose until Richter gave up his enterprise. Subsequently, the city council decreed that the salt would be produced under municipal management and sold exclusively at the local pharmacy, in 2-lot (34 g) packages, and only to present spa guests.
All this took place when David Becher was 7–10 years old, and this state lasted until 1763, when the now adult Becher met Count Rudolf Chotek, the highest Czech chancellor, in Karlovy Vary.
A New Method
He wondered how the city could profit from the sale of thermal salt when its production by burning expensive wood under kettles was extremely costly. Becher replied that he knew a way to make it incredibly cheaper "without fire and using the heat from the Hot Spring." He developed a detailed method, which was genius in its simplicity: he had a wooden vat made, into which he placed 10 shallow kettles filled with thermal water. The vat was then continuously flowed through by water from the Hot Spring at 72 °C, which could heat the kettles enough for the water to evaporate. It was, in a way, an energy perpetual motion machine; heat flowed from the Earth's interior for free, eliminating the high costs of firewood. Minerals remained at the bottom of the kettles, which were further processed into crystalline salt.
Rudolf Chotek forwarded Becher's "invention" to Vienna, and after a warm recommendation from Gerard van Swieten, the court physician of Empress Maria Theresa, an imperial decree was issued in 1764, allowing the production and sale of Karlovy Vary salt on a large scale according to Becher's recommendation. However, the condition was that the city was required to invest half of the proceeds into spa infrastructure "for the comfort of spa guests."
And thus began a long period of animosity and threats, as the citizens were certainly not willing to forgive Becher this "revolution" in existing practice. Libelous writings and pamphlets appeared on his door, and he occasionally heard dangerous threats. Between 1764 and 1783, the citizens filed a total of four complaints about the production and sale of salt, the last even to the emperor. Becher always responded with a new opinion, arguing that dissolving Karlovy Vary salt in ordinary water could not achieve the quality of mineral water drawn directly from the spring, and that while the salt sold well, it had no negative impact on the number of spa clients; on the contrary, the number of guests was gradually increasing. These were annoying, difficult years for him, considering that the sale of salt brought him no personal profit.
The End of Disputes
The disputes were definitively ended when, in the spring of 1783, Emperor Joseph II strictly rejected the citizens' fourth complaint. Increasing revenues from sales flowed cheerfully into the city treasury and from there into spa infrastructure. Paved promenades, retaining walls, lighting, parks, forest paths, viewpoints, water supply, school—all these were funded from the profits of thermal salt during Becher's lifetime. And also the first theater in Karlovy Vary, as we will discuss next time.
Images
- Title page of David Becher's phenomenal work "Treatise on Karlovy Vary" from 1789.
- Becher's vat (A) for the production of Karlovy Vary salt: hot water from the Hot Spring flows through the vat and heats the kettles (B), from which the thermal water evaporates. Minerals remain at the bottom for further processing.
