Sun Zi's Mathematical Classic

Four Jun Make One Shi While this heading refers to units of weight—specifically the shi (stone), which equals roughly 60 kilograms—the text immediately below defines the system of volume. In ancient China, weight and volume were fundamentally linked by the specific weight of a standardized crop: black millet.

The measurement of volume begins with a grain of millet.
Six grains of millet make one gui|original: 圭; the smallest base unit of volume.
Ten gui make one cuo|original: 撮; a "pinch".
Ten cuo make one chao|original: 抄; a "handful" or scoop.
Ten chao make one shao|original: 勺; a "spoonful".
Ten shao make one he|original: 合; often called a "cup," roughly 100ml in the Tang dynasty.
Ten he make one sheng|original: 升; a standard "pint" or liter.
Ten sheng make one dou|original: 斗; a "peck".
Ten dou make one hu|original: 斛; a "bushel" or "picul".

A hu contains sixty million grains of millet.

The reason we know this is as follows:
Six grains of millet make one gui.
Ten gui (sixty grains of millet) make one cuo.
Ten cuo (six hundred grains of millet) make one chao.
Ten chao (six thousand grains of millet) make one shao.
Ten shao (sixty thousand grains of millet) make one he.
Ten he (six hundred thousand grains of millet) make one sheng.
Ten sheng (six million grains of millet) make one dou.
Ten dou (sixty million grains of millet) make one hu.

Ten hu (six hundred million grains of millet) make six yi|original: 億; here representing 10^8.
One hundred hu (six billion grains of millet) make six zhao|original: 兆; here representing 10^9.
One thousand hu (sixty billion grains of millet) make six jing|original: 京; here representing 10^10.
Ten thousand hu (six hundred billion grains of millet) make six gai|original: 陔; here representing 10^11.
One hundred thousand The text ends here mid-progression, likely continuing to the next page to describe even larger denominations of measurement.