Read History in a Glacier

How can glacial ice in the Swiss Alps help us understand English medieval economy? Sounds strange but in the ice are elements such as lead which was heavily used in the economy.

They cut a core from the Swiss glacier about eighty yards long and contains two millennia of fallout from events such as volcanic eruptions, dust storms and lead pollution. Using a laser, scientists cut fifty thousand thin slices, four thousandths of an inch thick to study. Each slice represents weeks of snowfall and showed that the heyday for lead pollution was the Industrial Revolution when lead was used in paints, pipes and ceramics.

The second most active use was during England's medieval period, from eleven-seventy to twelve-nineteen and corroborates English pipe rolls which are records of taxes paid by miners for cart-loads of lead. Researchers saw lead levels dip after King Henry the Second killed Thomas Beckett, a popular archbishop of Canterbury. Mining slowed and tax collections declined. A decade later, when Henry patched up relations with the Pope and funded an Abbey, lead production and taxes increased to build the project. Soon, it dipped again during the civil war with Scotland and again when the Holy Roman Emperor imprisoned England's King, Richard the Lionheart.

Since the ice core in the study sat on the north-facing slope of the Swiss Alps, it received England's lead dust brought there by northwest winds over a distance of nine hundred miles. What a spectacular way to read history!