many other similar depressions, now visible in the low-angle afternoon light. They were all about the same size, and the closer we looked, the more we saw that they stretched in every direction around us. They seemed to show a pattern. Individual holes were lined up in two long rows, in something of a zigzag arrangement: left-right, left-right, left-right. Ribbons of them were crisscrossing much of the rock platform that we had been working on all day.
