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I have sometimes sat alone here of an evening, listening, until I have made the echoes out to be the echoes of all the footsteps that are coming by-and-bye into our lives.
He tried it; but in the darkness the distant echoes sounded so hideously that he tried it no more.
And all with pearl and ruby glowing Was the fair palace door, Through which came flowing, flowing, flowing, And sparkling evermore, A troop of Echoes, whose sweet duty Was but to sing, In voices of surpassing beauty, The wit and wisdom of their king.
Although to some it's a tantalizing speculation, the Maya researchers say they would be better convinced if other ruins also produced such echoes.
Terrestrial telescopes cannot resolve the light echoes of distant supernovas, says Schaefer, but two fairly close novas have exhibited the effect, Nova Persei 1901 and Nova Sagittarii 1936.