Volume provides a summary of the progress of each agricultural experiment station. Also includes statistics, a bibliography of experiment station publications, and selected studies.

Report published by the U.S. Bureau of Mines which is a compilation of accidents in quarries located in the United States with data regarding the number and kinds of accidents as well as information about the mining operations (e.g., number of men employed, kinds of quarries, amount of work performed, etc.).

Report compiled by the U.S. Bureau of Mines including statistics on fatalities in coal mines located in the United States as well as data regarding the various operations (e.g., number of miners employed and average production). The information is organized into tables for comparison and the text draws some overall conclusions in the summary.

From abstract of Bulletin: "The results of the experiments described in this bulletin are largely a record of the behavior of sponge iron as precipitant of lead and copper under laboratory conditions comparable to those that would obtain in a commercial plant were it attempted to secure the maximum contact of surface between solution and precipitant."

Volume provides abstracts of agricultural experiments conducted during the year. Also includes statistics, convention reports, bulletins, bibliographies and listings for Spanish edition publications from the Porto Rico Station. Name and subject indexes start on page 901.

Volume provides abstracts of agricultural experiments conducted during the year. Also includes statistics, convention reports, bulletins, and bibliographies. Name and subject indexes start on page 901.

Although the corrosion resistance of sheet duralumin can be greatly improved by suitable heat treatment, protection of the surface is still necessary if long life under varied service conditions is to be insured. The coatings used for this purpose may be grouped into three classes: the varnish type of coating, the oxide type produced by a chemical treatment of the surface, and metallic coatings, of which aluminum appears to be the most promising. Since the necessary weather exposure tests are not complete, some of the conclusions regarding the value of various surface coatings are necessarily tentative.

Report includes the National Advisory Committee for Aeronautics letter of submittal to the President, Congressional report, summaries of the committee's activities and research accomplished, bibliographies, and financial report.

Annual report submitted by the Boy Scouts of America to Congress describing highlights from 1927, activities, ideals, organizational leadership, and other information about scouting programs.