Transcription of letter
Kennetpans by Alloa N D 9 Nov 1786
I am favd with yours of 31 Oct. It is well you stopped proceeding with my Mill, before we had more fully determined upon the power. Mr Meickle Millwright is cleart of opinion my two pair largest stones should be four feet 6 in diameter and the two smallest pairs four feet. The power of the mill to be such as drive the two largest pairs at one time & at the rate of 112 turns per minet upon barey. The other pair smallest stones to turn also 112 times per minet both Mr Meickle & me are of opinion barey will rewuire a much larger power than wheat, we supose about 1/3 more.
You say Mr Latrap his Mill at present works two pairs of stones each grinding 12 bushells for flours & that you expect when a little smooth will make out 15 bushells.
Your Mr Mall in his letter to me of 1st Oct says “As soon as I know the result of Mr Latraps Engine I shall order the Materials, and if that Engine be short of my expectation in point of performance as for quality, I shall take it upon me to enlarge dimensions so as to be able to grind about 30 bushells for hours.”
His Engine he said was 11 horses power so would only charge about ten.
While I am erecting I do not wish to be hampered because my business were at any time requiring a double power. I have therefore now to desire you make with all possible speed go on and make me a mill of such size & power as will grind with the above stones sixty bushells for hours which your Mr Mall charges at twenty horses power. I would not incline to pay a higher premium than twenty horses, and that I will pay cheerfully if your mill grinds me sixty bushells for hours if left your charge to be in a rateable proportion.
My Mill house is now well advanced and I expect will be roofed in course of three weeks, the whole agreeable to your plan. The vent I have made 19 inches square I can have a sufficiency of water brought to the level with the found of the mill.
The boiler I intend making the bottom and under part of sides of Iron plates having a large parcell Gottenburgh plates by me. The top of copper or lead as you must approve of but the last I apprehend will do full as well as the copper and agree better with joining to the lead. Mr Erskine of Mar has a leaden top to his 15 feet boiler. It has stood exceedingly well for many years. The mill stones as I before wrote you I can get made here. I get a pick of above forty tons exceeding fine frence burrs newly imported from Rhone. I will attend to what you recommend as to an engineman. I will expect your draughts & drawings in course of a few days how to go on by, with every part of the Matchinery so far as can be done here the cylinder & other parts to be made with your. I earnestly request they may be got done & forwarded with all possible haste. I leave you to forward them by whatever conveyance you think best & most speedy, and upon no consideration let the smallest doubt or delay now interfeers
I am with regard
Your most Ob Serv