Bloodroot, Sanguinaria canadensis, is found throughout the temperate regions of the United States east of the Mississippi River. It was used by the Indians as a dye for coloring their garments and for staining their faces and bodies, in which direction it fulfilled the double object of a coloring material as well as to keep away insects, it being disagreeable to them. The Indians also used it as an acrid emetic and, mixed with other herbs, in the form of an ointment as an application to indolent ulcers, its action being somewhat escharotic. The early settlers employed it in these directions, while its efficacy in coughs and colds established it as a constituent of home-made compounds such as syrups and tinctures. The professional use as well as great reputation of this drug and its alkaloidal constituents (388a) are due to the Eclectic school of medicine, although its qualities had been well established previous to the systematic efforts made by physicians of this school. Sanguinaria was mentioned by Barton (43), Cutler (178), Thacher (631), Schopf (582), Bigelow (69), and other early investigators, whose recorded statements demonstrate the method of its introduction to have been as herein described. In connection with lard, arsenic, and hydrated ferric oxide it constitutes a once popular cancer remedy. It is a constituent of the early Eclectic Compound Tar Plaster (see Phytolacca).