They were written by experts under the supervision of the Scientific Department of the National Woman's Christian Temperance Union, published by the instigation of the same, and have been carefully revised from time to time, under the same supervision, to keep them abreast with the latest teachings of science. Being both teachable and well adapted to grade, their educational value, as proven by schoolroom tests, is of the highest order. We therefore cordially indorse and highly recommend the Pathfinder Series for use in schools. MARY H. HUNT, _National and International Superintendent of the Scientific Dep't of the Woman's Christian.
