Invented in 1923 by Wilhelm Ritzerfeld, ditto machines were popular among schools, churches, and clubs for making copies of worksheets, fliers, and so on before the modern copy machine became ...

Invented in 1923 by Wilhelm Ritzerfeld, ditto machines were popular among schools, churches, and clubs for making copies of worksheets, fliers, and so on before the modern copy machine became ...

But “technology had a contribution to make too: the Ditto machine, an innovation that requires its own aside,” ...