Patrick Graham, Minister of Aberfoyle, wrote the General View of the Agriculture of Stirlingshire for the Board of Agriculture. It was published in 1811. He includes a short, but detailed, account of threshing mills and their use in the county. This account was made when there was already a wide use of threshing in the county by a number of means, including horse power and water power. It is worth quoting at length:
“Suffice it to say, that thrashing mills, with their appendages of shakers, and winnowing machines or manners, are now very generally introduced into this county. Few or none who farm to any extent in the eastern and southern districts, want this first implement of husbandry. They are almost universally wrought by horses, water being for the most part scarce. The power of the mill is estimated by the number of horses that is necessary to work it; an indefinite estimate, it must be allowed, to persons unacquainted with the strength of the horses employed, but sufficiently intelligible in the district under consideration. We speak of a thrashing mill of a three horse power, a four horse and a six horse.
From the daily increasing price of wood, and of other materials of every kind, an ordinary thrashing machine costs from L60 to L200. A thrashing mill of a three horse power, in this county, about four years ago, L125. At the present day it would cost 25 per cent more. Ten men are employed whilst it is in use, in the various operations belonging to it; it thrashes at the rate of ten bolls of wheat every hour, or 100 bolls in a day often hours.Without enlarging on the utility of this machine, this may suffice to demonstrate the saving which it occasions. It is unnecessary to offer an estimate of the time, and the number of hands that would be required to thrash 100 bolls of wheat by the flail. It is reckoned that one third of the expense of labour is saved by the use of the thrashing mill.”
Graham also shows that the thrashing machines were already a labour-saving machine, though one that has increased in price in recent years.
The photographs of threshing were taken at B. A. Stores, Aberdeenshire, May 2018.