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208 a century and a half ago, but the chronograph, known for many years as the American method, is only half a century old.

One of the greatest astronomical researches has been the measurement of the exact positions of 166,000 stars. The sky was divided into twenty zones of which seven were taken by Germany, four by the United States and three by Russia. Of the American zones two were observed at Cambridge, one at Albany, and one at Washington. Each occupied the time of several astronomers for twenty years. It is now nearly time, after fifty years, to reobserve these stars to determine their motions. Fortunately, two new methods, the transit micrometer and photography, have been found which will greatly reduce the labor. The older department of astronomy, measuring the positions of the stars, has been left in America to the Naval Observatory. Unfortunately, the law requires that the superintendent must be a naval officer who can not remain long on land. The average term of office is less than two years. The average term at Greenwich is thirty years, where with but half the income, more than double the work is done. Congress, though repeatedly appealed to, will not remedy this great waste of the public funds.

Two million measures of the light of 80,000 stars have been made at Harvard. The results have been accepted by an international committee as the standard for the world. Such measures are likely in the future to be replaced by photographs taken with yellow light. A certain class of stars vary in brightness. Some increase in light many thousand times, others double their brightness in seven minutes with perfect regularity. Many thousand excellent observations of these objects are now obtained every year by amateurs having only small telescopes. Nearly five thousand variable stars are known of which three quarters have been found at Harvard. Astronomical photography, and American invention, replaces eye observations in almost all researches. Two Harvard telescopes have each taken 40,000 photographs whose combined weight is about forty tons. They give the only record on the earth of the history of the stars for the last quarter of a century. Photographs of the spectra of the stars to determine their motions form the principal work of the Lick, Yerkes, Greenwich, Potsdam and many other of the larger observatories. A catalogue of the spectra of 200,000 stars is now being compiled at Harvard, and will fill seven large quarto volumes.

The friendly cooperation of American astronomers has greatly advanced the work in this country, but it will be difficult to compete with the splendid observatories and instruments now lavishly furnished in Germany. If similar support is given us, the American Association for the Advancement of Science can fulfill its objects as regards astronomy.

in America has during the past month lost three of its most distinguished leaders—Dr. S. Weir Mitchell, the eminent physician, physiologist and man of letters, of Philadelphia; Dr, Seth C. Chandler, the astronomer of Cambridge, and Dr. Benjamin Osgood Peirce, Hollis professor of mathematics and natural philosophy at Harvard University.

economic botanist of the Bureau of Science of the Philippine Islands has been killed by natives in the Amboyna Islands in the Malay Archipelago.

is proposed to place a suitable memorial of the late Alfred Russel Wallace in Westminster Abbey. It is also proposed to present a statue or bust to the British Museum of Natural History and a portrait to the Royal Society. Contributions to the Alfred Russel Wallace Memorial Fund may be sent to the London and Smith Bank, Holborn Circus, London, E.C.