crucible of the purest soft or malleable iron was made out of heads of nails, and fitted with a stopper of the same metal, closely fitting. Into this a small diamond was put, the remaining space around the diamond was filled up with filings of the same iron, and the stopper rammed in very close. The whole was then inclosed in an earthen crucible, this last in a larger of the same material, and the whole closely luted, and exposed for about an hour in a very strong forge furnace. When all was cold, the crucible of iron was found melted down into a button of cast steel. This, when broken, exhibited a perfectly smooth, uniform fracture, and not a vestige of the diamond remained. The steel was exactly similar to that known in England by the name of cast steel. The inference from this curious experiment is, that as diamond will perform the office of charcoal, in converting iron into steel, its nature is the same or very similar to that of charcoal. DIANDRIA, in the Linnæan system of Botany, class of plants comprehending all those with hermaphrodite flowers, and only two stamina in each; such are sage, olive, phillyrea, jessamin, rosemary, &c. DIAPASON, in music, a musical interval, by which most authors, who have wrote upon the theory of music, use to express the octave of the Greeks, The diapason is the first and most perfect of the concords; if considered simply, it is but one harmonical interval; though, if considered diatonically, by tones and semitones, it contains seven degrees, viz. the three greater tones, two lesser tones, and “ two greater semitones. The interval of a diapason, that is, the proportion of its grave sounds to its acute, is duplicate, i. e, as 2: 1. DIAPASON, among the musical instrument makers, a kind of rule or scale, whereby they adjust the pipes of their organs, and cut the holes in their flutes, hautboys, &c. in due proportion, for performing the tones, semitones, and concords just. DIAPHRAGM, in anatomy, a large musculous membrane or skin placed transversely in the trunk, and dividing the thorax from the abdomen. DIARY, a table of days: See ALMANACK, The subjoined table, showing the days of the week that begin the several months for ever, is, to that effect, a perpetual diury : Month. A B E F G JANUARY Sun. Sat, Frid. Thu. Wed Tue. Mon FEBRUARY Wed Tue. Mon Sun. [Sat. [Frid. Thu. MARCH Wed Tue. Mon Sun. Sat. Frid. Thu. APRIL.... Sat. Frid. Thu. Wed Tue. Mon Sun. MAY Mon Sun. Sat. Frid. I hu. Wed Tue. JUNE Thu. Wed Tue. Mon Sun. Sat. Frid. JULY........ Sat. Frid. Thu. Wed Tue Mon Sun. AUGUST...... OCTOBER... Sun. Sat. Frid. Thu. Wed Tue. Mon This table is very plain; for having the dominical letter for the given year, find that on the head, and guide your eye down from it till you come opposite the month, and there is the name of the day of the week that begins that month. See DOMINICAL Letter. DIASTOLE, signifies the dilatation of the heart, auricles, and arteries, and stands opposed to the systole, or contraction of the same parts. DIATESSARON, a concord or harmonical interval composed of a greater tone, a less tone, and one greater semitone: its proportion in numbers is 4:3. The word diatessaron has of late years been applied by authors for a harmony of the four gospels. DICE, certain cubical pieces of bone or ivory marked with dots on each of the faces, from one to six, according to the number of faces. There are divers ways of making dice to suit the purposes of gamblers and villains: as by sticking a hog's bristle in them, so as to make them run high or low:-or by drilling and loading them with quicksilver, which cheat may be discovered by endeavouring to balance them by their diagonal corners, for if they are false, the heavy sides will, under such circumstances, always turn down. Dice are said to be of great antiquity, and to have been invented by Palamedes at the siege of Troy, for the amusement of the officers and soldiers. Dice like cards pay a very heavy duty to government, and cannot legally be imported. DICTATOR, in the policy of the ancient Romans, a magistrate invested with sovereign and even arbitrary power. He had the power of life and death; also to raise or disband troops, make war or peace, and that without the consent either of the senate or people, or being accountable for his proceedings. He was elected by one of the consuls in the night-time on the frontiers of the common-wealth, and no where else; and the ordinary duration of his office was only for six months, during which time all other magistracies ceased, the tribuneship excepted. Whenever he appeared in public, he was attended by twenty-four lictors, or double the number allowed a consul. However, notwithstanding all this power, he could not go out of Italy, or even ride on horse-back during a march, without leave from the people. This was accounted the safe-guard of the common wealth for four hundred years together, till Sylla and Cæsar, by assuming the title of perpetual dictators, converted it into tyranny, and rendered the very name odious. DIDELPHIS or Opossum, in natural history, is noticed for the singularity of its structure, which consists in the female's possession of a bag or pouch in the lower part of the abdomen, which is opened and closed at pleasure, and to which her young resort for shelter and security in a variety of dangers. The Virginian opossum is gentle and inoffensive. The female produces four or five at a birth, and prepares a sort of nest for herself of grass, near the root of a tree. She has the power of closing her pouch so completely as to render it a matter of difficulty to open it. See Plate Nat. Hist. fig. 9. The great flying opossum of New-Holland is nearly two feet in length to the beginning of its tail, which is likewise about two |