ScientificAmerican1897-12-18.jpg Scientific American 1899-03-04ThumbnailsScientific American 1897-11-13Scientific American 1899-03-04ThumbnailsScientific American 1897-11-13Scientific American 1899-03-04ThumbnailsScientific American 1897-11-13Scientific American 1899-03-04ThumbnailsScientific American 1897-11-13Scientific American 1899-03-04ThumbnailsScientific American 1897-11-13
The manufacture of steel tubing -- pipe mills at the National Tube Works, McKeesport, Pennsylvania. Pushing the skelp into the welding furnace. Welding flanges on a 22-inch pipe.



Source: Steve Kirch, collector, and creator of a great website about SCIENTIFIC AMERICAN in the past

Restoration by: magscanner