HIN

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HIN

HEPTAGONAL, consisting of seven angles, and there-fore also of seven sides.

HERBOSUM MARMOR, a species of marble, muchesteemed and used by the ancient architects and statuaries.It was of a beautiful green colour, but had always with itsome cast of yellow. It was dug in the quarries of Tavgetum,but was esteemed by the workmen the same in all respects,except colour, with the black marble dug at Tmnarus inLaca;demonia, and thence called Teenarian marble.

IIERRING-BONE, a term applied to a particular kindof masonry, in which the stones are laid aslant, incliningalternately right and left. Such work was common inRoman and Saxon structures.

IIERMOGENES, the inventor of the eustyle intercolum-hiation ; also of the octostyle pseudodipteros. He is men-tioned by Vitruvius , chap. 2. book iii.

HEWN STONE, any stone when reduced to a given formby means of the mallet and chisel.

HEXAEDRON, or Hexahedron (formed of IS, six , and>/2pa, seat) in geometry, one of the five regular bodies, popu-larly called a cube. See Cube .

The square of the side of a hexaedron is in a subtripleratio to the square of the diameter of the circumscribedsphere. Hence, the side of the hexaedron is to the diameterof the sphere in which it is inscribed, as one to the f 3 :and consequently it is incommensurable to it.

HEXAGON, (from !£, six, and yonna, angle) a figure ofsix angles, and consequently of six sides. If the angles andsides are equal, the figure is called a regular hexagon. Ifthe side of a hexagon be denoted by s, its area willbe 2.5980762 s.

HEXASTYLE, (from t£, six, and tv\oc, column) a build-ing with six columns in front.

HINDOO ARCHITECTURE. See Indian Archi-tecture.

HINGES, metal ligaments, upon which doors, shutters,folds, lids, &c., turn in the act of opening and shutting.

There are many species of hinges, viz., butts, rising-hinges,pew-hinges, easement-hinges, casting-hinges, chest-hinges,coach-hinges, desk-hinges, dovetail-hinges, esses, folding-hinges, garnets, weighty side, side-hinges with rising joints,side-hinges with squares, screw-lunges, scuttle-hinges, shutter-hinges, trunk-hinges, of various descriptions, liook-and-eye-hinges, and centre-pin-hinges.

HINGING, a branch of joinery, which shows the art ofhanging a board to the side of an aperture, so as to permitor exclude entrance at pleasure. The board which performsthis office is called a closure. The placing of hinges dependsentirely on the form of the joint, and as the motion of theclosure is angular, and performed round a fixed line as anaxis, the hinge must be so fixed that the motion may not beinterrupted : thus if the joint contain the surfaces of twocylinders, the convex one in motion upon the edge of theclosure, sliding upon the concave one at rest on the fixed body,the motion of the closure must be performed on the axis ofthe cylinder, which axis must be the centre of the hinges; inthis case the joint will be close, whether the aperture be shutor open. But if the joint be a plane surface, it must beconsidered upon what side of the aperture the motion is tobe performed, as the hinge must be placed on the side of theclosure where it revolves.

The hinge is made in two parts, movable in any angulardirection, one upon the other.

The knuckle of the hinge is a portion contained under acylindric surface, and is common to both the moving part andthe other part at rest; the cylinders are indented into each3 ther, and made hollow to receive a concentric cylindric pin

which passes through the hollow, and connects the movingparts together.

The axis of the cylindrical pin is called the axis of thehinge.

When two or more hinges are placed upon a closure, theaxes of the hinges must be in the same straight line.

The straight line in which the axes of the hi nges are placedis called the line of hinges.

The following are examples of the different cases.

The principle of hanging doors, shutters, or flaps, withhinges.

The centre of the hinge is generally put in the middle ofthe joint, as at A, Figure 1 ; but in many cases there is anecessity for throwing back the flap to a certain distance fromthe joint; in order to effect this, suppose the flap, when foldedback, were required to be at a certain distance, as A B in jFigure 2, from the joint; divide a b in two equal partsat the point c, which will give the centre of the hinge;the dotted lines b d e p, show the position when foldedback.

Note. —The centre of the hinge must be placed a smalldegree beyond the surface of the closure, otherwise it willnot fall freely back on the jamb or partition.

It must also be observed, that the centreof the hinge mustbe on that side that the rebate is on, otherwise it will not openwithout the joint being constructed in a particular form, aswill be afterwards shown.

Figure 3 shows the same thing opened to a right angle.

To hang two flaps, so that when folded back, they shall beat a certain distance from each other.

This is easily accomplished by means of hinges havingknees projecting to half that distance, as appears from Figure4;this sort of hinges is used in hanging the doors of pews, inorder to clear the moulding of the coping.

To make a rule joint for a window-shutter, or otherfolding-flaps.

Figure 5. —Let A be the place of the joint; draw AC atright angles to the flap, shutter, or door ; take C, in theline A c, for the centre of the hinge ; and the plain part A b,as may be thought necessary ; on c, with a radius, C B, describethe arc b d ; then will a b d be the true joint.

Note. —The knuckle of the hinge is always placed in thewood, because the farther it is inserted the more of the jointwill be covered, when it is opened out to a right angle, as inFigure 6 ; but if the centre of the hinge were placed the leastwithout the thickness of the wood, it would show an openspace, which would be a defect in workmanship.

To form the joints of styles, to be hung together, when theknuckle of the hinge is placed on the contrary side of therebate.

Figure 7.—Let c be the centre of the hinge, m i the jointon the same side of the hinge ; K l the depth of the rebatein the middle of the thickness of the styles, perpendicularto K m, and L F the joint on the other side, parallel to K m ;bisect K I. at ii, join H C; on n C describe a semicircle, C i h,cutting k M at l : through the points I and II, draw i n g,cutting f l at G ; then will fgim be the true joint ; but ifthe rebate were made in the form of iikif, neither of thestyles could move round the joint or hinge.

To form the edges or joint of door-styles, to be hung toeach other, so that the door may open to a right angle, andshow a bead to correspond exactly to the knuckle of the hinge.Also the manner of constructing the hinges for the variousforms of joints, so as to be let in equally upon each side.

Figure 8, No. 1, shows the edge of a style, or it may insome cases be a jamb, on which a bead is constructed exactlyto the size of the knuckle of the hinge, and rebated backwards,