David M. Guion, the All-Purpose Guru, is a librarian and multi-specialist. He has education, training, and experience in several subjects and publishes the fruit of careful research in order to proved reliable and accurate information. His two books on the history of the trombone place him among the world's foremost authorities on the subject--a very large fish in a very small pond. As a blogger and an author for the Amazon Kindle platform, he aims to be a reasonable sized fish in some roomier ponds: classical music, American popular music (before rock), sustainability and green living, resear...