charges which can be put on a given body than Dalton had ever discovered between combining powers or Front between atomic weights or Moseley between X-ray frequencies. The greatest common divisor of this series of charges is then the ultimate unit or atom of electricity which has been named the "electron." New evidence that it is indeed a universal and invariable natural constant will be brought forward and a new determination of its value will be presented.
It is obvious that as soon as we could assert that these electrons are found in the hydrogen atom it was necessary to suppose that a single hydrogen atom contains at least two such electrons, one positive and one negative, and as a. matter of fact the evidence is now strong that it consists of exactly two. This twentieth century has then discovered for the first time a new subatomic world of electrons, the constituents of atoms.
All this is definite and probably permanent. But atomic conceptions in more or less vague form have also begun to invade the one remaining field of physical investigation, namely, the field of ethereal radiations. The most significant of recently discovered facts in the domain of radiant energy are these:
(1) Ethereal radiations when absorbed by matter, if they are of high enough frequency, will detach one and only one electron from a single atom. (2) The energy transferred to this electron from the ether wave is independent of the intensity of the incident radiation. (3) It is also independent of the kind of matter from which the electron is taken, but (4) it is exactly proportional to the frequency of the ether wave which detaches it.
These facts are stated in an equation set up tentatively by Einstein in 190.5, and arrived at by him from the standpoint of a modified corpuscular theory of radiation. New proofs of the exactness of Einstein's equation will be presented and the evidence for and against Einstein 's conception will be discussed. Whether the conception ultimately stands or falls, it appears probable, at any rate, that an equation has been obtained which is to be of no less importance in future physics than Maxwell's equation of the electro-magnetic field, and which seems destined to undoors to the understanding of the relalock for the physicists of the future the tions existing between matter and radiant energy.
SCIENTIFIC ITEMS
We record with regret the death of Dr. Frederick Winslow Taylor, of Philadelphia, past president of the Society of Mechanical Engineers, known for his inauguration of methods of "scientific management"; of Dr. Edith J. Claypole, research associate in pathology in the University of California; of Dr. A. A. W. Hubrecht, professor of embryology in the University of Utrecht; of Professor Stanislaus von Prowasek, head of the zoological department of the Hamburg Institute for Tropic Diseases; of Sir George Turner, distinguished for his work on the rinderpest and on leprosy, from leprosy, contracted during research work to discover a cure for the disease, and of Lady Huggins, widow of Sir William Huggins, the distinguished astronomer, and known for her scientific work.
Miss Davy, niece of Sir Humphry Davy, has presented to the Royal Institution, London, a bust of the great chemist executed by Samuel Joseph in 1822.
The Royal Astronomical Society has by a vote of 59 to 3 passed a resolution approving of the admission of women as fellows and associates of the society, and requesting the council to take all necessary steps to render their election possible.
