DIDASCA'LIA, a term in use among the Greek writers of antiquity, and till within the last century among almost all the nations of modern Europe, applied to the representation of dramatic pieces, or to critical notices of the stage, and of every thing appertaining thereto.
DlDO'llON, in ancient architecture, a brick whose length was on foot, and its breadth one half its length.
DIE, a stamp used in coining, by which a piece of prepared metal is impressed with due force. Coins are generally com pleted by one blow of the coining-press. The engraver selects a forged plug of the best east steel of proper dimensions for his intended work, and having carefully an nealed it, and turned its surfaces smooth in the lathe, proceeds to engrave upon it the intended device for the coin. When this is perfect the letters are put in, and the circularity and size duly adjusted ; it is then hardened, awl is termed a matrix. Another plug of soft steel is now selected ; and the matrix being carefully adjusted upon it, they are placed under a very powerful fly-press, and two or three blows so directed as to commence an impression of the matrix upon the plug ; this is then annealed, and the operation repeated till the plug receives a perfect impression of the work upon the matrix. This impres sion is of course in relief, the original work upon the matrix being indented, and produces what is termed the punch.
This, being duly shaped in the lathe, is hardened, and is employed in the pro duction of impressions in soft steel or dies, which, being properly turned and hardened, are exact Jim-similes of the original matrix, and are used in the pro cess of coinage. When a pair of dies are made of good steel duly hardened and tempered, and are carefully used, they will sometimes yield from two to three hundred thousand impressions before they become so far worn or injured as to re quire to be removed from the coining presses.
DIES, (days,) in law, are distinguished into dies juridici, days on which the court sits for the administration of justice ; dies non juridici, days on which no pleas are held in any court of justice ; and dies datus, a day or time of respite, given by the court to a defendant in the cause.—Dies caniculares. in astronomy, the dog-days.—Dies critici, in medicine, days in which some diseases are supposed to arrive at a crisis—Among the Ro mans, days were distinguished in a Va riety of ways ; the most important of which were dies nefasti or dies atri, days devoted to religious purposes, on which it was unlawful to do any public business : dies .fasti, similar to the dies juridici of modern times; and dies feriati, like our dies non juridici, when the courts were shut.