Observations placeholder

Empedocles - The Clepsydra

Thus do all things draw breath and breathe it out again. [breath, spirit input, spirit output] 

All have bloodless tubes of flesh extended over the surface of their bodies; and at the mouths of these the outermost surface of the skin is perforated all over with pores closely packed together, so as to keep in the blood while a free passage is cut for the air to pass through.[meridians, trigger points] 

Then, when the thin blood [blood] recedes from these, the bubbling air rushes in with an impetuous surge; and when the  blood runs back it is breathed out again. 

Just as when a girl [feminine], playing with a water-clock [water clock] of shining brass, puts the orifice of the pipe upon her comely hand, and dips the waterclock into the yielding mass of silvery water -- the  stream [rivers and streams] does not then flow into the vessel, but the bulk of the air inside, pressing upon the close-packed perforations, keeps it out till she uncovers  the compressed stream; but then air escapes [perceptions] and an equal volume of water [spirit input] runs in, -- just in the same way, when water occupies the depths of the  brazen vessel [pitcher or jug] and the opening and passage is stopped up by the human  hand [portal], the air outside, striving to get in, holds the water back at the gates of  the ill-sounding neck, pressing upon its surface, till she lets go with her hand. 

Then, on the contrary, just in the opposite way to what happened before, the  wind rushes in and an equal volume of water runs out to make room.  Even  so, when the thin blood that surges through the limbs rushes backwards to  the interior, straightway the stream of air comes in with a rushing swell; but  when the blood runs back the air breathes out again in equal quantity.