Hundertpfund gives a good preparation made of paste and pipe-clay; the paste to be made of flour mixed with cold water and stirred until it looks like thick milk. Boil slowly for half an hour, stirring in warm water, and making a smooth, shiny paste. Lay some crumbled pipe-clay in water until it is penetrated and dissolved. Stir in water until it is as thick as the flour paste. Mix these two in equal quantities, and pass through a hair sieve. The mass should be as thin as for water-colour painting. Warm it again and pass it over canvas or board, while warm, until the pores are filled. Cover this thinly with an oil-color of white lead and oil of turpentine. Dry it, and scrape down any roughness with pumice-stone, washing off the dust. Spread again with the white oil-color, using no turpentine, as it must be thicker than before, in order to cover. Touch this with a badger-hair pencil, then sift over some fine flour, which will combine with the oil. Dust off the superfluous, and dry the canvas well in the sun.,