
All contemporary images showed that the loch is divided in two halfs, by two finger-like peninsulas protruding from either side. The fingers almost touch each other, leaving a ankle-keep, a few metres wide channel in between - the infamous Valve. Here the Valve in December 2019. The southern half is further subdivided by another finger, the peninsula. This is not the mystery.
The mystery was an old image I found on Geograph, which seemed to show that the eastern finger of the Valve was broader in summer 2005. I concluded that the loch must be a dynamically changing landscape, and decided to monitor it. Further research, conducted from the warm confines of my living room, revealed the banal truth. The image from 2005 was taken when the loch was still and the sun was out. The combination of mirror images of mountains and shadows of mountains make the finger look broader. There is no real change, just shadows and reflections. No real mystery either, just a normal puzzle. The field advances incrementally. The project is concluded.
