pressive. Yet the experiments are never the main things; they are always subordinate to the idea with which he is dealing—helps to its presentation. He is never eclipsed by his own pyrotechny, but holds the attention of his listeners closely to the question under examination. Prof. Tyndall is remarkable for the combination of two traits which are but rarely united in a single individual. He is an original explorer of scientific truth, and a skilful and effective public teacher. Holding the truths of science to be divine, he is impelled to dedicate his life to their discovery; but holding them also to be a means of salvation to man, he is impelled also to the duty of their public interpretation. The Royal Institution, in which he is professor, is admirably constituted for the attainment of this twofold end; providing equally for carrying out systematic original researches and for expounding their results to the select audiences that gather in its lecture-room. Sir Humphry Davy first gave it a world-wide reputation in both these departments; he was a fertile discoverer and an eloquent lecturer. Dr. Faraday succeeded him, and probably surpassed him in both of these accomplishments. The mantle of Faraday has fallen upon Tyndall, and the fame of the establishment has not suffered from the change."
Prof. Tyndall has long desired to visit the United States, to see his many friends, and to observe the aspects of American life; while multitudes in this country have reciprocated the desire, that they might have the opportunity of listening to his lectures. Yielding to their numerous appeals, he has prepared a course of six lectures, and brought with him a large amount of new and delicate apparatus, for illustrating them. The lectures will embrace the phenomena and laws of light: reflection, refraction, analysis, synthesis, the doctrine of colors, and the extension of radiant action in both directions, beyond the light-giving rays into the region of invisible action. Then will follow the principles of spectrum analysis, the polarization of light, the phenomena of crystallization, the action of crystals upon light, the chromatic phenomena of polarized light, and the parallel phenomena of light and radiant heat. These lectures will be a source of rare intellectual enjoyment to those who will have the good fortune to listen to them, and of which our citizens will not be slow to avail themselves.
We give, in the present number of the Monthly, the best likeness we have ever seen of Prof. Tyndall. He is a man of medium stature, lithe-built, highly vitalized, alert and noiseless in his movements; a ready and effective talker, but an excellent listener, and his manners are genial and attractive. He is socially strong, a man of the world, as well as a philosopher, and at home in all relations. But, with all his passion for experiment, he has not yet made the experiment of matrimony.
