The current Mrs Spod and I have recently returned from a week's cruise. Back on dry land we find ourselves still feeling that we are afloat with a not-unpleasant swaying. All to be expected of course BUT.. we both find that it is more pronounced in a bathroom / toilet. I include her in this question to indicate that it's nothing to do with standing up / sitting down. AND an acquaintance who owns a boat finds the same phenomenon every time she gets back to terra firma.
It is to do with the perception of the water level in the bath/toilet. You have spent a week with the water moving everytime you lool at it, so now you are home and it isn't, you move to compensate.
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