Every subject in this volume is fully discussed, and at the same time nothing is given which is not appropriate and even necessary. Thus a combination of completeness and conciseness is reached which is excellent. Among the most carefully and exhaustively treated subjects are copper, gold and silver, the platinum group of metals and coal and iron, though many others might be mentioned, for every subject undertaken has been thoroughly treated. In the article on copper the statistics of production and consumption, as well as the condition of the various domestic and foreign markets, are fully discussed by the editor, and, in addition, separate articles are also given on “American Methods of Ore Sampling and Assaying,” by Albert R. Ledoux, and on “Bessemerizing Copper Matte,” by Charles Wade Stickney. The article on the statistics of gold and silver is by Mr. R. P. Rothwell, editor of the volume, and is an excellent piece of statistical work, giving, as it does, the statistics of production of gold and silver in the world for a number of years back. To this article are appended interesting papers on the “Chronology of the Gold and Silver Industry, 1492–1892,” by Walker Renton Ingalls, on “Recent Improvements in Gold Chlorination,” by John E. Rothwell, and on the “Cyanide Process,” by Louis Janin, Jr. The article on the Platinum Group of Metals, by Charles Bullman, gives complete information regarding the production, consumption, nature of the deposits, metallurgy and uses of platinum and its related metals, iridium, rhodium, osmium, palladium and ruthenium. The articles on Coal and Coke and on Iron and Steel, both by Mr. Wm. B. Phillips, give full statistics of production and consumption, as well as interesting historical data, and reports of the condition of various markets. Many of the other articles in this volume deserve mention, but lack of space forbids further detail. It may be said, however, that everything necessary is presented, and nothing unnecessary or unreliable is given; in other words, the volume contains no trash.