This medicine was some years ago kept as a secret, and had great reputation as a lithontriptic, which indeed it seems in many cases to deserve. It was discovered by Dr Blackrie to be no other than soap-lye; and the following receipt for using it was procured by General Dunbar: "Take one tea-spoonful of the strongest soap-lye, mixed in two table-spoonfuls of sweet milk, an hour before breakfast and at going to bed. Before you take the medicine, take a cup of pure milk, and immediately after you have swallowed the medicine take another. If you find, this agrees with you for two or three days, you may add half as much more to the dose."