天工開物 (Tiangong Kaiwu) - Exploitation of the Works of Nature

Exploitation of the Works of Nature

Chapter 10: Forging

Library of Chinese Classics

A detailed line drawing illustration depicts the industrial process of forging a large iron anchor. The scene shows a massive four fluked anchor suspended by several heavy chains from a tall wooden scaffolding structure. A large group of workers, approximately ten men, on the right side are pulling on the chains to hoist or position the anchor. On the left, other workers use long handled tools and a large hammer to work on the metal. In the lower left corner, there is a large brick furnace with a circular opening displaying stylized flames, used for heating the iron. The traditional Chinese characters "Hammering the Anchor" original: 錘錨 (chuimao) are written vertically on the right side within the illustration's frame.

Chisels

Chisels are forged using wrought iron wrought iron: a low carbon, malleable iron that provides the structural toughness needed for the body of the tool and have blades embedded with steel steel: high carbon iron that provides the hardness necessary to maintain a sharp cutting edge. The body of the tool is circular and hollowed at the top so that a wooden handle can be inserted. When a chisel is being crafted, an iron pipe is first made to serve as a mold; this is referred to as a "ram’s head" original: 羊頭 (yangtou). The technique is identical to the process used for forging the handle of an iron spoon. To use the tool, one strikes the wooden handle with an axe, driving the chisel into the material. The blade of a chisel can range in width from one cun approximately 1.3 inches or 3.2 cm down to as narrow as three fen approximately 0.4 inches or 1 cm. When the task requires digging a round hole, the blade is shaped into a column, and the tool is then called a "scoop chisel" original: 剜鑿 (wanzao), often used for gouging or deep carving.

Anchors

When storms make it difficult for ships to pull into a berth, their very fates depend upon their anchors. The anchors used for warships and sea-going vessels can weigh as much as a thousand jin The Ming jin was approximately 600 grams; a thousand jin would be roughly 600 kilograms or 1,300 pounds..