Now that David Mawer of the Isles of Scilly Wildlife Trust has recorded the presence of gravelly deposits apparently of glacial origin on the west side of Samson, and now that Prof James Scourse has accepted that they may well be authentic indicators of Late Devensian ice, let's ponder on the precise positioning of the ice edge.
The map above is a first shot -- it will inevitably be corrected. But we can assume several things, since topographic controls will have come into play on this island which has two hills, each about a hundred feet high. First, there were probably lobes of ice pushing into the strait between Bryher and Samson, and into St Mary's Road to the south. On the island itself, the ice may have pressed against North Hill and South Hill without being able to override them. And there may have been a small lobe in the col between the hills.
Let's see how this all works out when somebody gets round to doing some more detailed fieldwork by following the shoreline right around the island.
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