Professor Clarke contributed the chapter Element to the last edition of Watts's Dictionary of Chemistry. He was made president of the Washington Chemical Society in 1885, and of the Philosophical Society of Washington in 1896. He organized and had charge of Government exhibits, on behalf of the Department of the Interior, at the expositions of Cincinnati, Chicago, Atlanta, Nashville, and Omaha. He is a corresponding member of the British Association, of the Edinburgh Geological Society, and of the New York Academy of Sciences. Correspondence. THE MOON AND THE WEATHER. _Editor Popular Science Monthly_: DEAR SIR: Scientific investigators in meteorology have again and again declared they have not been able to discover by accurate and long-continued observation that the moon has any effect whatever upon terrestrial weather; yet the farmers have, for unreckoned years, undoubtingly ascribed certain kinds of weather--changes, especially--to the moon; and, despite the dictum of the scientists, they have persisted in their confidence in the pale orb as a weather-breeder, and as a disposer, in a large degree, of the wet and dry features of the months. Now comes Mr. H. H. Clayton, meteorologist at the Blue Hill Meteorological Observatory, and shows by diagram and dates that the _electrical_ condition of the atmosphere varies in close accord with the position of the moon in her orbit. That electricity performs various offices in the atmosphere, notably among the particles of vapor, is well known; but just how and to what extent atmospheric phenomena result from electrical action has not yet been clearly demonstrated. However, we have now a scientific basis for the assumption that the moon has an influence on the weather. An interesting summary of present knowledge concerning the atmosphere is contained in Studies of the Upper Atmosphere, by A. Lawrence Rotch, director of the Blue Hill institution. The diagram of comparative altitudes, which forms the last illustration of my article on kite-flying, in the May number of this magazine, is from the frontispiece of Mr. Rotch's pamphlet just mentioned, for which credit was inadvertently omitted. GEORGE J. VARNEY. 57 CORNHILL, BOSTON, _August 19, 1898_. Editor's Table _THE GOAL IN EDUCATION._