lampblack, four parts of boiled linseed or cottonseed oil. Boil thoroughly, and reduce the mixture by adding spirits of turpentine so that it may be easily applied to a thin piece of pasteboard. Give three coats, drying between each coat. Finish by rubbing smooth with a piece of cotton waste soaked in spirits of turpentine. You have an excellent slate or memorandum book, which may be sold for ten cents. Use a slate pencil. Made in large quantities, these are very profitable.