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    Re: Refraction
    From: Ken Muldrew
    Date: 2005 Aug 26, 11:19 -0600

    I came across an interesting account of rather extreme refraction recently
    that shows just how dramatic the effect can be with large temperature
    gradients. The quote is from:
    Journal of a Voyage, made by order of the Royal Society, to Churchill
    River, on the North-West coast of Hudson's Bay; of Thirteen Months
    Residence in that Country; and of the Voyage back to England; in the years
    1768 and 1769; by William Wales. Philosophical Transactions (1683-1775),
    Vol. 60. (1770), pp. 100-136.
    "August 7th. About 5 saw the low land of Cape Churchill, bearing from the
    S. To S.W.b.S. but the haziness of the horizon made the land put on a
    different appearance every 4' or 5'. I cannot help taking notice of one
    circumstance, as it appears to me a very remarkable one. Though we saw the
    land extreamly (sic) plain from off the quarter deck, and, as it were,
    lifted up in the haze, in the same manner as the ice had always done; yet
    the man at the mast head declared he could see nothing of it. This
    appeared so extraordinary to me, that I went to the main-top-mast-head
    myself to be satisfied of the truth thereof; and though I could see it
    very plain both before I went up, and after I came down, yet could I see
    nothing like the appearance of land when I was there. I had often admired
    the singular appearance of the ice in these parts, which I have seen
    lifted up 2? or 3? at a distance of 8 or 10 miles, although when we have
    come to it, we have found it scarcely higher than the surface of the
    Ken Muldrew

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