Complex sentence: The Encyclopedia was initiated in 1912 as a historical and biographical record under the directorship of Charles H. Bertie, municipal librarian of Sydney, and a lot of material had been collected when the outbreak of World War I in 1914 temporarily halted its progress.
Split into simpler sentences: The Encyclopedia was initiated in 1912 as a historical and biographical record under the directorship of Charles H. Bertie, municipal librarian of Sydney. The outbreak of World War I in 1914 temporarily halted its progress.