For a discussion of zhong 鐘, "bushel," relative to early systems of dry-measure, see Zuozhuan, Duke Zhao, year 1.
This and the subsequent four sections of text all begin with gu, "and so." As Robin Yates has argued, these "soft gu" indicate seams within the text, where sections have been stitched together, rather than the more forceful "therefore" that gu sometimes implies (see "New Light on Ancient Chinese Military Texts," T'oung Pao 74 [1988], p. 219).