ScientificAmerican1920-09-11.jpg Scientific American 1912-10-12ThumbnailsScientific American 1923-11Scientific American 1912-10-12ThumbnailsScientific American 1923-11Scientific American 1912-10-12ThumbnailsScientific American 1923-11Scientific American 1912-10-12ThumbnailsScientific American 1923-11
New York's sky-line artisans: structural iron workers.