Complex sentence: In 1918 he was working for the Sperry Corporation and was living in Brooklyn.While working at the Pioneer Instrument Company, he designed the Earth Inductor Compass in 1924.
Split into simpler sentences: In 1918 he was working for the Sperry Corporation and was living in Brooklyn. World War I draft registration While working at the Pioneer Instrument Company, he designed the Earth Inductor Compass in 1924.