Recommendations of the Bureau of Animal Industry on Problems of Livestock Production

Résumé du livre

This bulletin gives the results of tests of all samples of ledge rock made by the Bureau of Public Roads to January 1, 1928, classified alphabetically according to location. In this revision of the earlier bulletins, each entry has been checked back to the original records, and a number of tests on manufactured road-building materials have been omitted. The results of tests of approximately 6,000 samples are now available in this bulletin, and these tests represent road-building material from practically all parts of the United States.