how a beginning xingqi breath circulation practitioner should count their heartbeats to measure time during biqi (閉氣, "breath holding"). When first learning to circulate the breaths, one inhales through the nose and closes up that breath. After holding it quietly for 120 heartbeats [approximately 90 seconds], it is expelled in tiny quantities through the mouth. During the exhalations and inhalations one should not hear the sound of one's own breathing, and one should always exhale less than one inhales. A goose feather held before the nose and mouth during the exhalations should not move. After some practice the number of heartbeats may be increased very gradually to one thousand [approx. 12 minutes 30 seconds], before the breath is released. Once this is achieved, the aged will become one day younger each day. (8, tr. Ware 1966: 138-139; times estimated by Needham 1983: 143-144) Fourth, using the ancient Chinese daily division between shengqi (生炁, "living breath", from midnight to noon) and siqi (死炁, "dead breath", from noon to midnight), it warns, "The circulating of the breaths must be done at an hour when breath is alive, not when it is dead. … No benefit is derived from practicing the circulating when breath is dead." (8, tr. Ware 1966: 139). Fifth, Ge advises maintaining moderation and tells an anecdote about his great-uncle Ge Xuan (164-244), a legendary Daoist who first received the Lingbao School scriptures. It must be admitted, however, that it is man's nature to engage in multiple pursuits and he is little inclined to the peace and quiet requisite to the pursuit of this process. For the circulation of the breaths it is essential that the processor refrain from overeating. When fresh vegetables, and fatty and fresh meats are consumed, the breaths, becoming strengthened, are hard to preserve. Hate and anger are also forbidden. Overindulgence in them throws the breaths into confusion, and when they are not calmed they turn into shouting. For these reasons few persons can practice this art. My ancestral uncle, Ko Hsüan, merely because he was able to hoard his breaths and breathe like a fetus, would stay on the bottom of a deep pool for almost a whole day whenever he was thoroughly intoxicated and it was a hot summer's day. (8, tr. Ware 1966: 140). Compare the above claim that with breath circulation, "one may stay under water or walk on it." The Baopuzi