87.7.28Last week, while monitoring the situation of the villagers from the scope in my survey room, I observed one of the natives swim out to a small object that appeared to be floating, but anchored, near the entrance to the bay. I ordered the object removed from the water for inspection. Several days later, however, I was surprised to see another floating there; the missing object had apparently, and quite mysteriously, been replaced with a new one overnight. I've long been aware of the existence of similar artifacts on the villagers' island, but have paid them little notice until now. Tomorrow I shall send surveyors to catalog the others.