Levy family.

The brothers Louis Edward Levy (1846-1919) and Max Levy (1857-1926) founded a photoengraving business in Baltimore in 1875. In 1877 they moved to Philadelphia and reorganized the firm as the Levytype Company. Here they introduced their invention (jointly patented on January 4, 1875) of a new photochemical engraving process, which they called "Levy-type".

In 1887, Louis E. Levy, assisted by his brother, invented the engraved glass grating known as the "Levy line screen," which became universally used for producing half-tone photoengravings. This was of immense value to the field of graphic arts. Other inventions followed, most notably the acid blast, or etching machine, in 1897, and the etch-powdering machine in 1901. In 1900 the firm was renamed the Graphic Arts Company, and the brothers added a printing and publishing department to their business.

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