During the first decade of the 20th century, French was frequently spoken on the West Virginia streets of such communities as South Charleston, the North View section of Clarksburg, and the small town of Salem. These neighborhoods shared a connection to the window-glass industry, and the people speaking French often were Walloons, or French-speaking Belgians. About 1900, changes in window-glass manufacture brought thousands of immigrants from the Charleroi area of Belgium just when the industry was expanding into West Virginia to take advantage of cheap natural gas and large deposits of silica sand. For a generation, window-glass factories, many of which were worker-owned cooperatives, relied heavily on these Belgian immigrants to provide the skills necessary to make West Virginia a national center of production.