No no not that one!
Founded in 1892 and closed in around 2009. Can't find all that much in the way of history other than it was owned by Edinburgh woolen mills and was one of Selkirk's largest employers in it's heyday.
Ben Cooper got to see the place as it was closing, and his report has a lot more to see than mine!
http://www.28dayslater.co.uk/exploring-heather-mills.t36864
But here is what remains today...