Purging Draughts.
Take of manna, an ounce; soluble tartar, or Rochel salt, from three to four drachms. Dissolve in three ounces of boiling water; to which add Jamaica pepper-water, half an ounce.
As manna will not sometimes sit upon the stomach, an ounce or ten drachms of the bitter purging salts, dissolved in four ounces of water, may be taken instead of the above.
Those who cannot take salts may use the following draught.
Take of jalap in powder, a scruple; common water an ounce; aromatic tincture, six drachms. Rub the jalap with twice its weight of sugar, and add to it the other ingredients.
William Buchan
Domestic Medicine 2nd edition 1785