If you can find a copy of "The Silver Sunbeam" by J. Towler 1864 (it was reprinted in 1969 by Morgan and Morgan) there are complete directions for making Tannic Acid from oak galls using ether. You can also make gallic acid from decomposed and moldy nut galls, but his takes about 3 months for everything to get good and moldy. The gallic acid can then be made into pyrogallol by heating it in oil This evidently was the best method in the 1860's and was widely used. I suppose I could copy the instructions if anyone is interested. This book is a very interesting look at the state of the art of photography in it's early years. Boy, do we have it easy!