Meanings of young compositor in английском

He had next tried Thomas Martyn, an ingenious young compositor, who had a scheme for a self-acting machine for working the printing press.

Mr. Walter next tried Thomas Martyn, an ingenious young compositor, who had a scheme for a self-acting machine for working the printing press.

Seeing that his young compositor was meeting with success and appreciation abroad, Mr. Anderson called upon him more frequently to write paragraphs for the "Gazette."