An ingenious work of art, intended to represent the solar system, was possessed by the monks of Croyland, and destroyed by the fire which consumed the abbey, in 1091. It was a table composed of different metals. The planet Saturn was of copper, Jupiter of gold, Mars of iron, Mercury of amber, Venus of tin, the Moon of silver, and the solar orb of brass. It is described by the monkish chronicler, Ingulf, as charming the eyes, and instructing the mind, by its precious materials, its brilliant colours, and its exquisite workmanship. This scientific instrument, however, was not the work of the monks themselves, but a present to the abbot of Croyland, by the king of France. Yet it seems that similar tables were not uncommon in England; and these, no doubt, were the handyworks of the monastic brethren, who alone understood scientific matters. Another proof of mechanical skill, not so well known, is to be found in an anecdote of St. Bernard and his friends. Weakened by his austerities, he retired to his cell, where he could not be persuaded to have a fire, but there were some who were more solicitous than himself to promote his comfort, and they contrived to introduce hot air into the apartment, through the stone floor under his bed.[3] There was a touch of good feeling, as well as of skilful contrivance, exhibited by these friends of the old abbot; whence it appears, that warming rooms by hot air is no modern invention, and that the reverence felt for genius and piety, and a desire to promote the comfort of those we love, are not peculiar to any age or country. Further light is thrown upon monkish employments in a letter written by Peter the Venerable, a friend and correspondent of the above-mentioned St. Bernard. After exhorting his friends to study and write, he says, "If, however, from its injuring your sight, or from its wearisome sameness, you cannot, or will not be content, with one manual employment, make a variety of other handy works. Make combs for combing and cleaning the heads of the brethren; with skilful hand and well-instructed foot, turn needle-cases; hollow out vessels for wine, such as they call _justitiœ_, or others like them, or try to put them together. And if there are any marshy places near, weave mats (an ancient monastic employment) on which you may always, or frequently sleep, may bedew with daily, or frequent tears, and wear out with frequent genuflexion before God; or, as St. Jerome says, weave little baskets with flags, or make them of wicker. Filling up all the time of your blessed life with these and similar works of holy purpose, you will leave no room for your adversaries to intrude into your heart, or into your cell, but that when God has filled all with his virtues, there shall be no room for the devil, none for sloth, none for the other vices."[4] They were truly odd employments which the abbot prescribed; yet, it is to be feared, that many of the brotherhood were far from being always so well employed;