Complex sentence: In the United States several dozen firms produced non-electric vacuum cleaners in the early 1900s, 1914 being the peak year, and three different models were sold by Sears, Roebuck between 1909 and 1917.
Split into simpler sentences: In the United States, several dozen firms produced non-electric vacuum cleaners in the early 1900s; 1914 being the peak year. Three different models were sold by Sears, Roebuck between 1909 and 1917.