In its introduction, it identifies six periods in the history of the state which have contributed to the establishment of local names: The seventh edition contains 6,252 entries, with references to another 2,679 names scattered throughout the text.[1] Entries are listed in alphabetical order, beginning with A B Crossing, a railroad station in Coos County,[2] and ending with Zwagg Island, an island near Brookings, Oregon.[6] The seventh edition also includes a CD-ROM with a complete biographic and geographic index as well as various maps of Oregon locations.[8] His daughter, Mary McArthur, reportedly took over editorship for the book's upcoming 8th edition.Oregon Geographic Names (Seventh ed.).