This illustration depicts an HVAC technician working on a gas furnace. Natural Gas Furnace Pipe - Tube Furnace Man
Vintage engraving of a Cupola furnace. A cupola or cupola furnace is a melting device used in foundries that can be used to melt cast iron, ni-resist iron and some bronzes. 1884 [b]View More:[/b] [url=http://www.istockphoto.com/file_search.php?action=file&lightboxID=10203398][img]http://www.walker1890.co.uk/istock/istock-mach.jpg[/img][/url] [url=http://www.istockphoto.com/file_search.php?action=file&lightboxID=2789749][img]http://www.walker1890.co.uk/istock/istock-engraving.jpg[/img][/url] Furnace Printmaking Technique Foundry Cupola furnace
Vintage engraving of men using a 19th Century puddling furnace in an ironworks. Puddling was an Industrial Revolution means of making iron and steel. View More: puddling Foundry Steel Mill Puddling furnace
Vintage engraving of a 19th Century Blast Furnace [b]View More:[/b] [url=http://www.istockphoto.com/file_search.php?action=file&lightboxID=10203398][img]http://www.walker1890.co.uk/istock/istock-mach.jpg[/img][/url][url=http://www.istockphoto.com/file_search.php?action=file&lightboxID=2789749][img]http://www.walker1890.co.uk/istock/istock-engraving.jpg[/img][/url] Metalwork Melting Furnace Blast Furnace
Vintage engraving from 1864 a Blast Furnace, a type of metallurgical furnace used for smelting to produce industrial metals, generally iron. View More: Ilustration Steel Mill Industry Blast Furnace
Vintage engraving of men using a flame furnace for Smelting, 19th Century. View More: Industrial Revolution Old-fashioned Factory Flame furnace
Vintage engraving of men using a shaft furnace, 19th century. Metalwork Mineral Furnace Shaft Furnace - Metalworking