The standing stone on the Houston Estate used to be situated somewhere in the area of what is now Harrysmuir Road in Pumpherston, just to the East of Livingston.
Harrysmuir Road - Approximate Site of the Houston Stone
Unfortunately, although the stone is indicated on a plan of the estate from 1759, it had been removed by the middle of the nineteenth century. Click here for a location map provided by StreetMap.
As can be seen from the OS map of 1853, however, while no standing stone is marked, there are two bench marks indicated at either end of the street, either of which could be the stone (or not!):
Harry's Muir Road, OS Map, 1853