Let’s Visit a Salt Mine
By “Awake!” correspondent in Austria
“THOMAS, how would you like to join us in visiting a salt mine?” This 10-year-old from our neighborhood was enthusiastic about the idea, and we were delighted to have a companion for our 12-year-old son. Our destination? Hallstatt, an old salt-mining village in the Austrian Alps.
Arriving at Hallstatt, we park our auto and then walk to the cable car that will take us up to the salt mountain. From the windows, we get a breathtaking view of the lake of Hallstatt and the majestic mountain that rises steeply from its shore.
Hallstatt’s Field of Graves
Leaving the cable car, we are on our way to the miners’ house. Our walk takes us across a huge field containing more than 2,000 graves. About 1,300 of these have been opened and have yielded up to 10,000 objects from the time between about 950 and 390 B.C.E. Already at that early period systematic salt mining was being done here. Discoveries at this site and elsewhere in the area have enabled archaeologists to reconstruct the period of civilization from 750 to 450 B.C.E. so well that it came to be known as the “Hallstatt period.”
The findings reveal that the people believed in continued existence after death. Among the objects buried with the deceased were urns, bowls, pails, weapons and jewelry.
In a meadow lying at an altitude of 1,370 meters (4,495 feet), graphite clay pottery has been excavated. On the bottom of nine of the vessels the potter had carved signs into the moist clay. One of these figures looks like a fork with several prongs. The work Alte und Neue Funde aus Hallstatt (Old and New Finds from Hallstatt) states that the figure is considered to be a character of an ancient script. We further read: “It is already found in the oldest letter script of Semitic alphabets as well as in the complement of letters of ancient Greek inscriptions.” The sign is thought to be a symbol for “rain.” The book Vom Amulett zur Zeitung (From Amulet to Newspaper) points out that, as an early pictographic symbol, this particular sign appears earth wide during “mythologically oriented stages of civilization.” It goes on to say: “Variations of such signs can be found in Mesopotamia, in Greece, in northern Europe (Hallstatt culture), among the [American] Indians, and in China.” Thus, even the remote valley in the Hallstatt area evidently did not escape being influenced by Mesopotamian culture and religion.
A Tour of the Mine
But now we are anxious to tour the mine itself. At the miners’ house protective coveralls are provided for visitors. Since the sizes are distinguished by a different color, we easily find a garment that fits.
A short distance above the miners’ house lies the tunnel entrance to the mine. A miner welcomes us with his typical salutation, Glück auf! (the miner’s “good luck!”). The passage leading into the mountain’s interior was hewn in the year 1719. Our guide tells us that we are going to walk some 300 meters (980 feet) in the tunnel leading through the cap rock. An impermeable coating prevents the large salt deposits from being leached. Earlier, the outer layer may also have contained salt. But gradually this salt may have been washed out, leaving impermeable clay to shield the salt deposit underneath.
Several minutes later we come to a larger crosscut tunnel. From here, a slide made of polished tree trunks leads to a large cavity below. The four of us seat ourselves in the steep slide and, with a little push from our guide, find ourselves zooming downward through the tunnel. The slide’s extension brakes our movement, and before us lies a huge cavernlike space. It is 2,000 square meters (21,528 square feet), with a volumetric capacity of 3,700 cubic meters (4,840 cubic yards).
Our guide explains that this area previously served as a dissolving installation. To open such an installation, the miners blast out an underground cavity of about 20 by 40 meters (65 by 130 feet). By means of a tunnel, like the one through which we slid, fresh water is poured into the cavity, filling it to the ceiling. The water dissolves the salt, and insoluble matter sinks to the bottom. After six or eight weeks, 100 liters (26.4 gallons) of water will contain 31 to 33 kilograms (68 to 73 lbs.) of salt. As the water leaches the salt, the cavity ceiling rises higher and higher, and the cavity itself moves upward. Depending on the salt concentration, each extraction process leaches from 50 to 150 centimeters (about 20 to 60 inches) off the ceiling. This process may be repeated from 50 to 70 times. Then the saline solution or brine is run off. For this purpose, the miners have cut not only a sloping tunnel leading to the cavity but also a horizontal one underneath through which a pipe runs for draining the brine. The dissolving installation is then closed.
Continuing our tour through the interior of the mountain, we climb the steps alongside the slide by means of which we gained access to the huge cavity. Eventually we find ourselves some 800 meters (2,600 feet) from the entrance passageway and, measured from the surface, some 400 meters (1,300 feet) underground. Again the four of us roller coast down a slide and are greeted by a spectacular view of a subterranean lake. Lights of various colors illuminate the cavity and the water reflects the letters forming the miner’s salutation Glück auf!
The installation is larger than the first one we saw. Its ceiling extends over an area of 3,800 square meters (40,900 square feet), and the volume of this cavity amounts to 15,300 cubic meters (about 20,000 cubic yards). By means of a path around the underground “lake,” we are able to view the installation from every side. The reflection of the ceiling in the lake’s heavy, very saline brine is so clear that we can recognize every detail as in a mirror.
Our Tour Draws to a Conclusion
The path through the subterranean cavities leads up to a pit with several information boards. Our guide explains to us that the brine is transported in a 40-kilometer (25-mile) pipe and is then processed, finally to become salt for industrial purposes or for the dining table.
At the conclusion of our tour we climb a flight of winding steps and again reach the entrance tunnel. Our guide invites us to sit down on a small railed car. The tunnels have a slight gradient of about 1.5 percent. This is enough for us to ride into the daylight at the exit.
We truly learned much, and time passed quickly in the miners’ subterranean realm. Thomas told his parents: “I haven’t had such a nice day for a long time.” Our son added: “What an experience!”