Illustrated Explanation of the Chariot System in the Artificers' Record

Its circumference is one ke and a half a diameter of four feet five inches. It is also said that the spoke length is one ke and a half four feet five inches is the total length of two spokes. It is further said that its width is three inches and its thickness is one-third [of the width] each spoke measures two feet, two inches, and five-tenths in length.

It is also said that the geng original: geng. Likely referring to the raised edge or the thickness of the tire/rim. is one inch. It is further said that the qu original: qu. The felloe or outer rim of the wheel. is "three ke tripled" the outer circumference of the wheel felloe is twenty-seven feet; the design of the large cart is described as "spacious".

The diameter of the hub and the circumference of the wheel both employ the method of "diameter of one to circumference of three" The ancient Chinese approximation of Pi (π ≈ 3), used before more precise calculations were standardized.; they do not use the "precise ratios" original: mi lü. Referring to more advanced mathematical constants for Pi developed by later scholars like Zu Chongzhi. used by later people.

The hub original: gu. The central part of the wheel. is where the spokes original: fu. converge; the hollow interior of the hub is called the sou literally "the marsh," a metaphor for the hollowed-out basin of the hub..

The Record of Trades original: Kao Gong Ji. states: "Measure across (jing) its lacquered interior and divide that in half to determine the hub's length." Jing original: 桱. is the term for measuring across the interior of an object The term jing shares phonetic roots with the words for "light" and "breadth." In the Book of Documents as well as the Book of the Later Han (in the "Biography of Feng Yi"), it is read as "horizontal." The Book of Han (in the "Biography of Wang Mang") explains this as having the same meaning as "horizontal," as the sounds for "light" and "yellow" are closely related. "Light" shifts in sound to "breadth," and "breadth" derives its sound from "yellow," which itself contains the sense of "horizontal." Therefore, the Erya The oldest surviving Chinese dictionary. states: "Fine breadth fills the cloth," and the Fangyan An ancient dictionary of regional dialects. states: "The breadth of cloth is called 'filling.' " This refers to the concept of horizontally filling a space while measuring an object. The sounds for "light" and "breadth" shift again to encompass the meanings of "expanding through the nine heavens" and "horizontally enveloping the six directions." These all share the same conceptual root. "Expansion" and "extension" are also phonetically related. The Fangyan says: "To stretch the small to make it large is called kuo (expansion)." The Huainanzi A 2nd-century BCE philosophical and scientific text. says: "Below, one calculates the three..."