National Geographic : 1977 Sep
Husky Austrian miners pick away at rock salt (above)in a 17th-century painting. Slow backbreaking labor sufficed when salt was used mainly for seasoning and preservation of food. Now more than 70 percent of the demand comes from industry. Salt or its de rivatives go into everything from plastics to mouthwash, and from aspirin to dynamite. VOLKMARWENTZELANDNELSONH. BROWN In the heart of Austria's Alps at Hallstatt, miners of the first millennium B.C . cut salt slabs that left behind distinctive shapes (above). The harvest became a commodity by which the Celts spread their culture. Some clothing and tools (right) were pre served in the mine; the bronze pick is nearly identical to those wielded 2,000 years later.