Mysterious Melted Forts

Some readers will know that we spend some time characterizing glass-like properties of proteins obtained by cooling to low temperatures. Well, another kind of glass transition happened in various Iron Age forts in Western Europe. Something heated them up, melted the rock, and on cooling the rock vitrified. Here's one that the admirably knowledgeable John Dye kindly took us to see  -The Torr in Shielfoot, Argyll.

Photo: Stephine Smith.

John and his colleagues managed to reproduce the vitrification in the lab using a temperature of 850C.
But why would the ancients have done this?  Destruction? Ceremony? Analytical chemistry can tell us nothing about how the temperature was achieved and even less about the motives for the burning.

Golden Eagles in Tennessee and Scotland

Good to read in the Knoxville News Sentinel that Golden Eagles may be soaring above the East Tennessee mountains somewhat more frequently these days. I remember them from the 1980s in North-West Scotland, where my father and his wife lived, in a place called Achnanellan, on the banks of Loch Shiel. Achnanellan is hidden in the wilderness, an old 17th century croft house with no road (you have to cross the Loch to get to it) and no neighbours within 4 miles. A place of ferocious weather and swarms of midges, of rich lichen and peat.

Here it is - the croft is a tiny white speck in the middle:

Achnanellan means "Field Near the Island", the island being St. Finnan's Isle, a windswept ancient burial ground. I set foot on it, and wondered at the dour, very old crosses (below). The locals had divided half of it for Protestants and half for Catholics, and placed pennies in the trees as votive offerings. There was maybe one burial per year there in the 1980s, probably many more before the brutal Highland clearances. The old bronze bell in the ruined chapel was still there, rumored to be a thousand years old - no-one had stolen it.

As for the eagles, they were always far above our heads, 1000 ft or so, hunting rabbits with acuity from on high. They fly in monogamous pairs and look like flying planks. It was difficult to fully appreciate their 7-foot wingspan from that distance, but pictures of one digging its talons into a cameraman truly bring home their size and power. Achnanellan, St. Finnan's Isle and Loch Shiel belonged to the eagles.