A kitchen midden, which is essentially a prehistoric rubbish heap, the accumulated shells, bones, and domestic debris left by past inhabitants over generations, was marked on a sketch plan published by Henry in 1945. The notation "K.M" appears on the map, pointing to a spot at the island's north-eastern end. The trouble is that the map itself is imprecise enough that no one can say with confidence exactly where the midden lies.

The most plausible explanation is that Henry's marked midden is the same deposit later identified within the ruins of a prehistoric house in the same general area. That house site has its own separate record, and the midden exposed within its collapsed walls may well be the feature Henry noticed and noted down nearly eighty years ago. What makes this small puzzle quietly interesting is that no trace of any second midden is now visible at the northern end of the island. The sketch plan, drawn with the loose hand of mid-century fieldwork, has left behind a question that the landscape itself declines to answer clearly.