The majority of comets travel in an ellipse, and those of short period, like Encke’s comet, make short journeys and may be considered frequent visitors to the neighborhood of the sun. Others are long-period comets, such as Donati’s (described in the following chapter), since it requires nearly two thousand years for the round trip. Finally there is a third class of adventurous comets which dash in from outer space, swinging swiftly round the sun in the focus of its curve, and darting off again with no prospect of returning, since they cannot possibly get round the other focus. Whence they have come or whither they have gone, no man knows! They are like the sparrow referred to in a simile used by a courtier in the days of King Edwin, who compared its fleeting visit to the life of a man: “It is as a sparrow’s flight through the hall when you are sitting at meat in winter tide, with the warm fire lighted on the hearth, but the icy rain storm without. The sparrow flies in at one door, and tarries for a moment in the light and heat of the hearth fire, and then flying forth from the other, vanishes into the wintry darkness whence it came.” CHAPTER THREE THE STORY OF DONATI’S COMET Hast thou ne’er seen the comet’s flaming flight? Th’ illustrious stranger, passing terror sheds On gazing Nations, from his fiery train Of length enormous, takes his ample round Thro’ depths of ether; coasts unnumbered Worlds, Of more than solar glory, doubles wide Heaven’s mighty cape; and then revisits Earth, From the long travel of a thousand years. —YOUNG. “Night Thoughts.” When a comet draws near to pay its respects to its ruler, the sun, it usually assumes a splendor befitting this momentous occasion. It adorns itself with a glittering train millions of miles in length, and composed of myriads of particles reflecting the sun’s light. The head is often enveloped in a multiplicity of transparent veils, through which bright jets may be seen emanating from the star-like nucleus within. Some comets have been seen with five or six trains, spread out like that of a peacock, the camera revealing rapid and marvelous changes in their appearance, during the course of a few hours. No fair débutante, about to be presented to royalty, could vie with a comet in capriciousness regarding her raiment, nor could she equal it in splendor, even though she owned the mystic lamp of Aladdin.