THE National Academy of Sciences held its semi-annual meeting at Columbia College, New York, October 28th-30th. Prof. W. B. Rogers presided. The meeting was welcomed by Prof. F. A. P. Barnard (President of Columbia College), as being the first use that has been made of the new building recently constructed and not yet quite finished, on the western front of the college grounds; thus appropriately inaugurating it in the interests of science. Prof. Rogers opened the meeting with a few brief but eloquent remarks, descanting on the far-reaching character of the researches which are now most prominently before the scientific world. As instances he cited the proofs brought by Prof. Whitney of the discovery of human remains in the pliocene; the evidence adduced by Mr. Lockyer, showing that in the sun many of the elements may prove to be compounds; the marvellous expositions of “radiant matter” in Mr. Crookes's experiments; and the striking discoveries in the uses of electricity and the telephone. Prof. Rogers is not ready to accept all the new theories which accompany these novel conceptions, but he feels assured that we are on the road toward new truths. The present age, like that which preceded the Newtonian era, has brought together a vast and somewhat chaotic mass of observations, out of which great principles shall be determined. In this work it is to be expected that some of the members of the Academy will bear an active part.