n - a b c - m

The flow and ebb is double in one and the same basin, because it will occur many times at the mouth of such a basin before the great [tide] is present in the great basin. And this happens because the wave of the first flow runs strongly into the basin, and in the time that this wave continues its impetus, the wave at the mouth makes its ebb; and before the wave that engulfs itself feels the ebb of that mouth of the basin, the flow is already reborn at that mouth, and in that time the engulfed wave stops, slackening its impetus, when the second engulfment of the second wave is reborn; and thus so many of these waves engulf themselves that the basin, being raised, its waters return backward with impetus, and the ebb that returns backward from that mouth no longer engulfs itself into the third or fourth [wave] until that first water has been disgorged.