The Mystery of the Carved Stone Balls
All across Scotland, for centuries people have been unearthing mysterious carved stone balls. (Which archaeologists, in a fit of whimsy, refer to as "carved stone balls" or if you want to be really technical, "petrospheres.") Imagine grinding a rock into a roughly spherical shape, then carving semi-circles out of its side.
These smoothed semi-circles are called "knobs," and were typically decorated with either straight cross-hatching, spirals, or concentric circles. Sometimes quite elaborately, and other times in a very plain style. Most of them have six "knobs," which forms one on each face if it were a cube. But they have been found with other numbers, with the record so far being a carved stone ball featuring 160 knobs.
