Sleep is necessary to the happy to prevent satiety, and to endear life by a short absence; and to the miserable, to relieve them by intervals of quiet. Life is to most, such as could not be endured without frequent intermission of existence: Homer, therefore, has thought it an office worthy of the goddess of wisdom, to lay Ulysses asleep when landed on Phaeacia. It is related of Barretier, whose early advances in literature scarce any human mind has equalled, that he spent twelve hours of the four-and-twenty in sleep: yet this appears from the bad state of his health, and the shortness of his life, to have been too small a respite for a mind so vigorously and intensely employed: it is to be regretted, therefore, that he did not exercise his mind less, and his body more: since by this means, it is highly probable, that though he would not then have astonished with the blaze of a comet, he would yet have shone with the permanent radiance of a fixed star. Nor should it be objected, that there have been many men who daily spend fifteen or sixteen hours in study: for by some of whom this is reported it has never been done; others have done it for a short time only; and of the rest it appears, that they employed their minds in such operations as required neither celerity nor strength, in the low drudgery of collating copies, comparing authorities, digesting dictionaries, or accumulating compilations. Men of study and imagination are frequently upbraided by the industrious and plodding sons of care, with passing too great a part of their life in a state of inaction. But these defiers of sleep seem not to remember that though it must be granted them that they are crawling about before the break of day, it can seldom be said that they are perfectly awake; they exhaust no spirits, and require no repairs; but lie torpid as a toad in marble, or at least are known to live only by an inert and sluggish loco-motive faculty, and may be said, like a wounded snake, to "drag their slow length along." Man has been long known among philosophers by the appellation of the microcosm, or epitome of the world: the resemblance between the great and little world might, by a rational observer, be detailed to many particulars; and to many more by a fanciful speculatist. I know not in which of these two classes I shall be ranged for observing, that as the total quantity of light and darkness allotted in the course of the year to every region of the earth is the same, though distributed at various times and in different portions; so, perhaps, to each individual of the human species, nature has ordained the same quantity of wakefulness and sleep; though divided by some into a total quiescence and vigorous exertion of their faculties, and, blended by others in a kind of twilight of existence, in a state between dreaming and reasoning, in which they either think without action, or act without thought.