Sir

A favourite bedtime book of mine is Alfred Russel Wallace's The Malay Archipelago (Macmillan, London, 1869). During my last read I found the following description of what sounds like a tsunami. Wallace in turn quotes from William Dampier's Continuation of a Voyage to New Holland in the Year 1699 (Knapton, London, 1703).

“We heard a dull roaring sound like a heavy surf, ... the roar increased, and we saw a white line of foam coming on, ... as our boat rose easily over the wave. At short intervals ten or a dozen others overtook us with great rapidity, and then the sea became perfectly smooth as before. I concluded at once that these must be earthquake waves; and on reference to the old voyagers we find that these seas have long been subject to similar phenomena.

“Dampier encountered them near Mysol and New Guinea, and described them as: ‘... strange tides, that ran in streams, making a great sea, and roaring so loud that we could hear them before they came within a mile of us. ... These ripplings commonly lasted ten or twelve minutes, and then the sea became as still and smooth as a millpond. ... We had one night several of these tides, ... we heard them a long time before they came.’ ...

“Some time afterwards I learnt that an earthquake had been felt on the coast of Gilolo the very day we had encountered these curious waves.”