The Physiomedical Dispensatory by William Cook, M.D., 1869
Chalk is a peculiar form of carbonate of lime, occurring abundantly in some mineral deposits, and forming a large portion of the shells and bones of the different classes of animals. Waters containing carbonic acid not unfrequently hold a small portion of it in solution; and this renders some waters in limestone districts purgative to those unused to them. Large beds of it exist along the southern coast of England; and it is also found in quantities in the north of France, and in small beds in some parts of the United States. It is not used medically in its coarse state, except as it or other fine qualities of carbonate of lime may be employed in the preparation of lime.
Prepared chalk is simply a good quality of chalk reduced to a very fine powder. The article is first pulverized, and then rubbed into a thin paste with a little water in a wedgewood mortar. Then fill the mortar with water, and stir the whole well, in a circle. In a few seconds the coarser particles will separate, and then the turbid liquid may be decanted into another vessel, where the minute particles of the chalk will slowly subside. The water being poured off from this, the soft mass is dried upon a muslin stretcher at a heat of not over 200E F.
Uses: This is a mild antacidits oxide of lime uniting readily with any acid, and throwing off its carbonic gas. It is prescribed in diarrhea with acidity of the stomach and bowels; and sometimes in acid forms of dyspepsia and gout. The salts it forms are nearly inert, or at least not purgative; and when mixed in a simple sirup with cinnamon, pimento, and other spices, is a pleasant preparation for children with laxity of the bowels. Sugar, or sugar and gum arabic, are needed for its suspension with water. A child may use from ten to fifteen grains three times a day. Sometimes it is sprinkled upon burns and ichorous sores as an absorbent, antacid, and stimulant.
Medical Herbalism journal and medherb.com