No. 5---University Series. SCIENTIFIC ADDRESSES BY PROF. JOHN TYNDALL, LL. D., F. R. S., Royal Institution. I. On the Methods and Tendencies of Physical Investigation. 2. On Haze and Dust. 3. On the Scientific Use of the Imagination. NEW HAVEN, CONN.: 1870. PUBLISHER'S NOTE. The first of the addresses of Professor Tyndall here published, i. e., that on the "Methods and Tendencies of Physical Investigation," was delivered at Norwich on the 19th of August, 1868, before the Physical Section of the British Association for the Advancement of Science, of which section Professor Tyndall was the President. The second, on "Haze and Dust," was delivered as a lecture before the Royal Institution of Great Britain-in which Institution Professor Tyndall is professor of physics-on the 21st of January, 1870. A note by the author, supplementing it in certain directions, was published in "Nature," vol. I, page 449, March 17, 1870. The third address, on the "Scientific Use of the Imagination," was delivered before the British Association at its meeting held in Liverpool, in September last. TYNDALL'S ADDRESSES. I. On the Methods and Tendencies of Physical Investigation. The celebrated Fichte, in his lectures on the "Vocation of the Scholar," insisted on a culture for the scholar, which should not be one-sided, but all-sided. His intellectual nature was to expand spherically, and not in a single direction. In one direction, however, Fichte required that the scholar should apply himself directly to nature, become a creator of knowledge, and thus repay, by original labors of his own, the immense debt he owed to the labors of others. It was these which enabled him to supplement the knowledge derived from his own researches, so as to render his culture rounded, and not one-sided. Fichte's idea is to some extent illustrated by the constitution and the labors of the British Association. We have here a body of men engaged in the pursuit of natural knowledge, but variously engaged. While sympathizing with each of its departments, and supplementing his culture by knowledge drawn from all of them, |