Enquire within upon everything by Robert Kemp Philp

One bushel of small coal or sawdust, or both mixed together, two bushels of sand, one bushel and a half of clay. Let these be mixed together with common water, like ordinary mortar; the more they are stirred and mixed together the better; then make them into balls, or, with a small mould, in the shape of bricks, pile them in a dry place, and use when hard and sufficiently dry. A fire cannot be lighted with them, but when the fire is lighted, put two or three on behind with some coals in front, and the fire will be found to last longer than if made up in the ordinary way.