Preston Mill has hardly changed for over 500 years although electricity was added shortly after 1960 for lighting. Water is brought by a lade from the nearby River Tyne to power the mill wheel which until 1959 milled oats for the local community.  Now the National Trust of Scotland demonstrates how the mill operated and the gruelling work that the miller had from lifting heavy sacks of oats to ensure that the oats were dry and free of contaminates like poisonous corn cockle seeds and the Trust illustrates the  preparation to make the grain suitable for animal or human consumption.  A spark from metal machinery or equipment could cause devastating fire so spades and shovels were made using wood and metal cog wheels link with wooden cogs.  Several inscriptions  on the outside wall mark the levels of a series of floods that affected the mill during more recent years with one in 1948 rising above the upper floor of the mill building. The photo shows the kiln.
We were told of some of the expressions that originated from milling, such as rule of thumb,  show your metal, put through the mill.
Our much travelled visitors were impressed as  they had never seen a similar mill.    A very comprehensive description is here