25 Above is the view as you start to descend (in a north westerly direction) from Glenstivon Dod into the saddle between it and Drumelzier Law (Drumelzier is pronounced "Drummellier" by the way). Like you I wondered what the white thing was half way down the hill.
Below, looking down into the Hopecarton Burn glen we get this view of the route we came up from Craig Head to Taberon Law on the other side of the valley (see the second picture on page 07 for a view over to here from that ridge). Then there is Gathersnow Hill, Culter Fell, Chapelgill Hill, Cardon Hill and Tinto beyond - with Worm Hill in front of them on the far side of the Tweed valley. They are all so familiar by this stage of the day.