with the complex methods of engineering, civil and mechanical, which again call for a thorough mastery of mathematics, is necessary. Mineralogy and petrography, metallurgy and mining engineering have each reached a stage of development entitling them to the rank of separate sciences, but the practical training of the geologist should include them all. When we add the biological sciences connected with historical geology, paleontology, zoölogy and botany, with all the laboratory and field work required for their proper study, we have a group of affiliated branches of learning requiring four or five years of continuous study after the student has learned how to study. It is plain therefore that only a specialist, one who is willing to neglect other studies, or who has previously had a liberal training, can perfect himself on the practical side in the science of geology. But irrespective of its practical uses, as a means of training and supplementary to the ordinary studies of a college curriculum, geology is one of the most useful of the sciences of observation. It is in providing that particular training to which President Eliot has recently called attention in the _Forum_ (Dec., 1892, Wherein Popular Education Has Failed), that geology can be used to such advantage. Speaking particularly of the lower education, President Eliot says it is "the judgment and reasoning powers" that particularly require attention. Their systematic development is to be attained in the four directions of "observing accurately, recording correctly, comparing, grouping and inferring justly, and expressing cogently the results of these mental operations." (p. 421.) The attainment of these ends is one of the purposes of liberal education, whether it be in the primary school or in the university. And geology, or any other science, is of value in a college course in proportion to its fitness for the exercise and development of these functions of the student. Geology may be taught without regard to these ends, and then it is valuable from the practical point of view, but when we examine it in respect of its availability as a disciplinary study we find it offering particular attractions.