I had never heard of a ‘Woad mill’ until I was trying to find information about the Horse Gin at Swannington which is elsewhere on this site and one of the people I was pestering mentioned an uncle in the 1960's was researching a horse powered Woad mill. I just had to follow this up. With my research I initially came across a really useful publication 'Woad in the Fens'  by Norman T Wills that provided a wealth of information about the subject. From other information that Mildred Cookson and the Mills Archive trust made available to me with including photographs and extracts with drawings from publications by Rex Wailes. This gave me with the information to produce my drawings of three of the mills. There was mention of a fourth mill, Brothertoft. It said "This mill has been fully described and illustrated and much quoted; for it was here that the first attempt at the mass production of woad was made". It may have been in 1936 but not so in 2019. Eventually in a paper by Betty Brammer  The Holland Fen: social and topographical changes in a Fenland environment, 1750-1945. I found a reference to a book that showed two illustrations of the mill. I managed to buy a reprint of the book - General View of the Agriculture of the County of Lincolnshire (1813) by Arthur Young and with the description about the operation of the mill. I was able to produce my drawings of that mill as well

Much of the information about the mills is based on the text from a book by Rex Wailes and the paper presented on February 19 to the Newcomen Society in 1936 - Preparation of Woad in England. In their paper read by Messrs. H. O. Clark and R. Wailes, the authors said that, after being cultivated for centuries, dyer's woad (Isatis tinctoria) was last grown and prepared at Skirbeck, Lincolnshire, in 1932, and that it is not likely to be grown again either in England or elsewhere. Much has been written on the history, botany and chemistry of the plant and the dye, and the object of their paper was to place on record information as to the technology and the cost of the preparation of woad. Fortunately, on farms at Algarkirk and Skirbeck, the machinery used in the industry had remained almost intact and photographs had been taken of it. These are the mills I've been able to draw from the information recorded and shared by the people and institutions above. I hope you find the information and drawings interesting and useful.