Believe the area you are referring to was recently Bridgend Building Supplies.
Away back it was Crear's Sawmill which then came to be known as the Thurso Steam Sawmill so I am guessing the chimmney is associated with the steam engine that drove the machinery in the sawmill.
The mill was then owned by a Mr Munro (and family) - he was the father of Hettie Munro who ran the Ships Wheel antique shop with her brother Alistair (where the Bistro is now).
Many older people always referred to the area as Munro's Woodyard even after it passed into the ownership of Bobby Riddell.