Artaxerxes had such an intense horror of fleas that he would not go to bed without a suit of armour, made like a night-gown, to fit close to his skin. He would lose his reason for days when bitten by one. There was a reward of ten talents, during his reign, for the apprehension of every flea, dead or alive; and merchants would come from far and near to claim the reward. Queen Elizabeth had the strongest antipathy to a sheriff's officer: she would run away as fast as she could directly she saw one, and continue running for miles, until her guards, who knew her weakness, stopped her. Old Parr would turn pale if he touched a piece of soap: this is the reason he never shaved. Cicero had such an antipathy to the Wednesday that he used to remain in bed all that day; and Anna Bolena could not hear the word "potato" pronounced without turning violently red, and feeling low-spirited for weeks afterwards. Charles the Second never could go through Temple Bar. It used to take the whole strength of Villiers, with Rochester and Nell Gwynne, to push him through it. Cromwell never could pass a tripe shop without bursting immediately into tears. AN ESSAY ON COMETS. BY OUR OWN ASTRONOMER. The word "comet" has been derived by some from the Latin _coma_, a tail; but the better derivation is _comma_, because it never can come to a full stop. Every comet has a tail, or train, which may be compared to some of those monster trains which are occasionally the subjects of newspaper paragraphs. What a comet is we do not exactly know. It is certainly an eccentric body, but there are so many eccentric bodies in these days, that this hypothesis affords us no assistance. A comet has a curious propensity to cut and come again, at very long intervals. Astronomers talk of the mean distance of a comet from the earth, but as no comet ever came nearer than several thousands of miles, which is anything but a mean distance, we should be glad to know the meaning the astronomers attach to the word alluded to. There is a comet due in 1848, being the same one that favoured us, or rather our ancestors, with a visit at half-past eight P.M., on the 21st of April, 1556. As the "oldest inhabitant" will not have had the honour of a previous acquaintance, it is very possible that some other eccentric body may be mistaken for our old acquaintance of the sixteenth century. Perhaps an inferior planet, disguised in a long tail, may endeavour to pass himself off for the expected visitor. The safest mode of predicting a comet is to prophesy its appearance at least a century hence, and something luminous is pretty sure to turn up, to enable posterity to find something like a realization of the prediction. Any astronomer desirous of naming an earlier day for the appearance of a comet should stipulate for its being visible at some outlandish locality, where no witnesses will be in attendance to test the accuracy of the prediction.