​HARTS' HORNS, are the horns of the common male red deer.— ​The scrapings, or raspings, of this animal's horns are medicinal, and employed in decoctions, ptisans, or cooling drinks, &c.

Harts-horn jelly is remarkably nourishing, and sometimes given in cases of diarrhœa: a decoction of burnt harts-horn in water is, however, generally substituted for this purpose.

The coal of harts-horn, which is prepared by exposing it to a strong and long-continued fire, changes into a very white earth, called calcined harts-horn. It is employed medicinally as an absorbent, and likewise in dysenteries, which are supposed to arise from acrid and ill-digested matter.

The salt of harts-horn is sudorific, and has been successfully prescribed in fevers: it yields a very penetrating spirit, which is useful to persons of weak nerves, or subject to fainting fits; though the preparation generally used, is distilled from bones, after extracting the oil. The latter is more grateful to the stomach, retains its limpidity for a much longer period, and is consequently superior to that obtained from harts-horn. This valuable substitute, however, is frequently adulterated by means of quick-lime. In order to detect the fraud, let a small portion of strong spirit of wine be mixed with the suspected volatile spirit; and, if a white powder be separated, let it subside, till the fluid can be decanted. A little of the sediment is then to be poured into a spoon, and held near a fire, or over the flame of a candle: if the powder be completely dissipated, the spirit is not prepared with lime, and contains a due proportion of volatile salt; but, if any remain in the spoon after it has been exposed to a moderate heat, it may be concluded that quick-lime, and other pernicious ingredients, have been employed.