Arkansas true Democrat., 1858-09-22

This rare visitor is now visible to the nak co eye in the early mornings and evenings. As fl is seldom we have an opportunity to make such distinguished acquaintance, we beg leave to in. troduce him to our readers.
 There are thirteen comets denominated great or grand. Of these, two appeared in the seven teenth century, three in the eighteenth and five the present century. The remaining three belong to the years 1264, 1472 and 1856. But the present comet is supposed to be that of body appeared then and now
 This reduces the number of grand comets to twelve. All comets that return within hun- dred years are called comets of short periods: those beyond handred years are called comets of long periods.
 The returns of the comets of short periods can be calculated with extreme certainty. but one that requires three hundred years to tra- verse its orbit, is difficult for several reasons. It has long been favorite speculation wi h astronomers that the comets of l264 and 1556 were identical. Assuming this identity they set themselves to calculate it's return. About twenty years ago, an English and French asiro- homer, each agreed upon the year 164S, as the time of its return. Between the years 1843 and l647, J. R. Hind, the celebrated astronomer, investigated the question anew and determined Its orbit On that basis, German astronomer undertook and accomplished the enormous la- Dor of computing the effect of the comets or bit of the messes of Jupiter, Saturn, Uranus, and the new planet Neptune, and partially of the Earth, Venus and Mars.
 His calculations fixed the return on August 2, 1858. These calculations, based as they were on the orbits of the comets of 1264 and 1856, prove their identity.
 Our visitor is now quite small and his tail is apparently about three degrees. In 1856 he was more brilliant. He was carefully charted by two astronomers. One writer describes it n "a great and brilliant star" Its apparent diameter is said to have been equal to half tha of the moon and its tail to have resembled "the flame of torch agitated by the wind" The tail in that year was described as being four degrees only.
 In 1264 it was still more brilliant. The de- scriptions we possess are very vague, but they state that its splendor greatest in the latter part of August aud when the head was just visible above the eastern horizon, the tail stretched out past the mid-heaven towards the west, and was nearly hundred degrees long. Our new visitor is too far of to be dangerous, for even was the cometic atmosphere as dan- .gerous as Sir Isaac Newton supposed. yet it may quiet the nerves of our lady readers to tell them that he is six millions of miles dis tant.
 It IS an old belief thst comets presage ex- traordinary events. The fall of empires, deaths of Kings. heat of summer. prevalence of cpl demics, spots on the sun. large meteors and inordinate fertility in the human species, are among the alleged accompaniments of great comets. Their purposes have given rise to much speculation. Some supposed them to ns material heIls where the wicked were al. 'eFraiely exposed to the burning heat of the suh aud then sent oil into space where the cold must'bs irssnse beyond conception. They are Singular visitors and their composition and pur. Poscs must forever remain mystery.