Author:Charles William Campbell
Articles in Popular Science MonthlyEdit
Some or all works by this author are in the public domain in the United States because they were published before January 1, 1928.
The longest-living author of these works died in 1927, so these works are in the public domain in countries and areas where the copyright term is the author's life plus 95 years or less. These works may be in the public domain in countries and areas with longer native copyright terms that apply the rule of the shorter term to foreign works.