After having produced glass since 1911 with “Lubbers” machines, by which human glass blowers were replaced with machine operators, the glass company Crengeldanz participated in the purchase of a license to manufacture flat glass using the revolutionary Fourcault process. In 1925, it installed four Fourcault-machines in Witten. The process involved a vertical drawing shaft, which elevated the glass upwards against gravity over several floors allowing it to cool down slowly. On the highest floor, workers cut the glass into single pieces.