Page:The New International Encyclopædia 1st ed. v. 06.djvu/273

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DIEPPE. 229 DIES AND DIE-SINKING. ivorj'. There are also ship-building yards, sugar- retiueries. rope-walks, and distilleries. The fish- ing lleet of Dieppe is large and important, and almost all the inhabitants of PoUet are engaged either in the lot'al or Newfoundland fisheries. Dieppe is a favorite landing-place of English tourists visiting France. Population, in 1891, i'2,.3.5U; in 1001, 22.839. In the eleventh century Dieppe appears as a mere hamlet, but, after its consolidation with some of the neigh- boring villages, it attained considerable impor- tance as a trading centre. In 1442 it held out sucecssfully against a besieging force of English under Talbot. The merchants of Dieppe were early noted for their enterprise, and ships from this port visited Brazil and the East Indies in the sixteenth century. The prosperity of the town was destroyed by the expulsion of the Huguenots, who formed a large proportion of the inhabitants. In 1094 it was bombarded by the English and Dutch fleet, and utterly de- molished. Though speedily rebuilt, it could not meet the competition of its rival Havre, and failed to regain its lost importance. DIERVILLA, di'er-vil'la. See Weigela. DIES AND DIE-SINKING (OF. de, det, Fr. d^. Sp.. Port.. It., dodo. die. from Lat. datus, p.p. of dare, to give). The art of making and using dies for stamping coins is of very ancient origin. Old coins have been found which show that it was known to the Greeks at least B.C. 800. The use of dies for stamping, shaping, and cutting out metals and other materials is of much more recent origin, and reached its present develop- ment only in the closing years of the last cen- tury. The use of the punch and press for cut- ting metal forms is said to liave been practiced in a crude way by a German blacksmith of the fifteenth century. Presses for sliaping as well as cutting metal were invented by T. Grif- fiths, of England, in 1841, but they were de- veloped in France, where they were ap- plied to the production of kitchen uten- sils. Recently presses have been utilized in many other branches of manufacture besides those dealing with metals. The use of dies, for instance, plays an important part in the modem shoe factory, and. in fact, in all indus- tries where a given form has to be produced repeatedly, whether the material be metal, leather, cloth, or paper. The most recent de- velopment in the art of using dies has been in the direction of working cold steel into numerous complicated forms, which were formerly pro- duced only by easting and forging. The astonishing cheapness of numerous sheet- ff.etal products is mainly due to the use of dies, which accompli-h. by a single stroke, the work which formerly required long and tedious manip- ulation. A striking example is the modern bicycle, a large proportion of whose hundred parts are formed l)y the power press. Not only kitchen utensils, but jewelry, boxes, pens, but- ton>. and the thousand and one familiar objects which were formerly worked into shape with the hammer, or soldered together out of separate pieces, are now struck between two dies of suit- able form. Dies, in general, are in pairs, consisting of a male die or punch, and a female die, which are so adjusted on a power press that one fits accu- ratelv into the ntbr.r Oftfn. tmucver, in cutting the less resistant materials, as leather, cloth, or paper, the two parts of the typical die are not required. The punch is simjily forced by a power hammer through the materials, against a fiat surface. In an article in the t'nginceiing Magazine (Xew York) for March, 1898, on "The Development of Machinery for Sheet - Metal Stamping," Oberlin Smith divides the kinds of work done by stamping into four general classes: "(1) Cutting, in which arc included punching and shearing; (i) forming, including bending, embossing, and curling; (3) drawing and re- drawing, which are more than forming, since the metal is subjected to an extensive distortion or molecular flow, incident to the changing of a flat, annular disk into a cylindrical, or conical, or hemispherical form of smaller average diam- eter, its surface being meanwhile rigidly con- fined to prevent wrinklings; (4) coining, with which should be includeil drop-forging, the metal in both cases being treated as a liquid and simply pumped, as it were, into the shape desired, the molecular flow being very gi'eat, and the whole object being treated as is a pat of butter or a cake of soap in the molds provided for its new incarnation." The simplest forms of cutting dies are the blanking dies, used for cutting out flat blanks from steel, iron, or other material. A sheer edge is given either to the punch or to the die, accord- ing to the work to be performed. When, as in cutting buttons, it is the blanks that are to be used, the sheer edge is given to the die ; but when the hole is the object sought, as in making rivet-holes in boiler-plates, the .sheer is given to the punch. Compound eutting dies are used for cutting fine work, where the relation of the centre or other holes to the outside must be per- fect, as in blanks for watch and clock movements, and sheet-iron disks for the armatures of dyna- mos and electric motors. A compound die has for its upper half a punch set into a die. and for its lower half a die set into a punch ; one stroke of the press thus performs the work that would require two or more operations if done on plain dies. Xeedle dies are used for punching eyes "in needles. The die is made in three pieces, securely fastened together. The centre piece pro- jects above the surface of the two side pieces, and into the groove of the needle. Thus the needle is supported while Iieing punched. This centre piece has a U-shaped slot, equal in width to the length of the eye of the needle. The press is so arranged that the needle is first stamped and then punched, the speed of the punch at the moment it enters the eye of the needle being very slow. Bending dies are simple when the metal is bent at a single angle, and complex when a loop is required, as in making armature connections, switciiboanls. and the like. Draning dies are dies which are used for 'drawing up' or shaping metal into such forms as basins, thimbles, and bells. In some complex dies the metal is shaped, stamped with a design, and cut, all by a single stroke of the press, as in making black- ing-box covers. Very often, however, in pro- ducing the more complicated forms of drawn work, the object is put through several dies before it attains its completed sliaiie. The erank- hanger of an ordinary bicycle lias to pass through a dozen or more presses before the flat sheet of ^ti'cl is transformed into the piece of