saponine

This plant imparts to water the property of forming a lather, from a principle it contains called saponine, which is allied to the active constituent of sarsaparilla, and as a substitute for which it is frequently used.

Resources of the Southern Fields and Forests, Medical, Economical, and Agricultural. Being also a Medical Botany of the Confederate States; with Practical Information on the Useful Properties of the Trees, Plants, and Shrubs 1863

One of the principles referred to is said not to differ from saponine.

Resources of the Southern Fields and Forests, Medical, Economical, and Agricultural. Being also a Medical Botany of the Confederate States; with Practical Information on the Useful Properties of the Trees, Plants, and Shrubs 1863

It is also rich in _saponine_, and is used for washing clothes; 2 ounces of the bark is sufficient to wash a dress.

Catalogue of Economic Plants in the Collection of the U. S. Department of Agriculture William Saunders 1861