I should have been clearer that this is a purely visual perception and that I'm puzzled by what aspects of the surroundings cause these strange perceptions. That flow is not an issue is shown by the sense of traveling west up Chirk cutting, but down the feeder from Trevor to bridge 34W. This latter section is interesting because initially there is little view on either sides, basically trees with odd glimpses of hills on the right and the dee valley on the left, then you come round the bend with the straight leading very clearly down to bridge 34W. This sense of down comes over even on photographs (they are all on my computer in Edinburgh - sorry).
What aspects of the surroundings affect these perceptions? I used to think that in cutings it was whether the canal curved to the right, a sense of downhill, or left, a sense of uphill, as in Chirk cutting. The same is true of Woodeaves cutting, but what about the section from Market Drayton to Tyrley locks. When heading south for me this is clearly uphill, wide open canal with trees on both sides across the embankment, the view opens up just before the bridge but still uphill, then it bends to the left in a deepening cutting and you're still going uphill, then a final long straight in a deep cutting and it's still uphill to the lock (and the reverse as you head back north). All very odd. Is there and "??ologist" somewhere whohas down research on any area of perception related to this? ((Maybe I shouldn't have started this topic: this used to a matter of "hm that's funny" but having put it into words it could become an obsession.)