Adze

An edged tool used by carpenters to chip surfaces lying in a horizontal position, or in situations where they cannot easily be cut with an axe.

Angle

A term in geometry signifying a corner, or the point where two converging lines meet. Angles are of three kinds; viz., right, obtuse, and acute. A right angle is formed by a line joining another perpendicularly, or at an inclination of 90°, which is one quarter of a circle. In an obtuse angle, the inclination of the lines is greater or more open than 90°. In acute angles, their inclination is less than a right angle. A solid angle is the meeting of three or more plain angles at a point.

Angle-Brace

A piece framed across the angle of a piece of framing. It is also termed an angle-tie, or diagonal tie, and is nearly synonymous with brace.

Angle-Rafter

A piece in a hip-roof at the line where the two adjacent inclined sides unite. It is continued from the eaves to the ridge, and serves to support the jack-rafters.

Aperture

An opening through a wall or partition. "Apertures," says Sir Henry Wotton, "are inlets for air and light: they should be as few in number, and as moderate in dimensions, as may possibly consist with other due respects; for, in a word, all openings are weakenings.

A

Adhesion

A physical term, denoting the force with which a body remains attached to another when brought in contact. Cohesion is the force that unites the particles of a homogeneous body. The insertion of a nail into wood is accomplished by separating the particles, and thereby destroying the cohesion; and its extraction, by overcoming the adhesion and friction. Adhesion, as related to woods, may be considered as follows: 31. nails, 18 of which weigh 1 pound, 11/4 in. long, when driven 1/2 in. into spruce, across the fibres of the wood, require a force of 73 pounds to extract them. A 6d. nail, driven 1 in. into dry oak, resists a strain of 507 pounds; and when into dry elm, 378 pounds. If the same nail be driven into elm endwise, or parallel with the grain, it may be drawn out by a strain of 257 pounds. The adhesion, therefore, when driven into the wood named, across the grain, or at right angles to the fibres, is greater than when driven parallel with them, as 4 to 3. In dry spruce, it is nearly as 2 to 1. A common screw, a fifth of an inch in diameter, has an adhesion about three times as great as a common 6d. nail. If the nail last named be driven 2 in. into dry oak. it will resist a direct strain of nearly half a ton.

They should not approach too near the angles of the walls; for it were, indeed, a most essential solecism to weaken that part which must strengthen all the rest."

Apron

The horizontal piece in wooden stairs supporting the carriages at their landings.

Arc

A term in geometry signifying any portion of a circle, or curve.

Arris

The intersecting line where two surfaces of a body meet.

Arris-Fillet

A piece of wood, triangular in section, used to raise the slates or shingles which are against any portion of the work projecting from the roof; as a party-wall, sky-light, chimney, battlement. etc.

Artificer

One skilled in any mechanical art; an inventor, or contriver.

Artisan

A mechanic trained to manual dexterity in any art or trade.

Ashlering

The short studs of a building between the plate and girt of the attic-floor. Buildings are framed in this manner where the attic is designed for occupation; the short studs cutting off the acute angle which the rafters would make, were they permitted to come to the floor.

Auger

A tool used by carpenters for boring holes.

Auxiliary Rafters

Pieces of timber framed in the same vertical plane with principal rafters, placed under and parallel to them to give additional strength to the truss. (See Plate XI.)

Axe

An instrument for hewing timber or chopping wood. The axe is of two kinds; the broad axe for hewing (the handle of which is usually so bent as to adapt it for hewing either right or left), and the narrow axe for cutting, etc.

Axis Of A Dome

A right line passing through its centre, and perpendicular to its base.

B

Back

The side opposite the face of any piece of work. When a timber is in a horizontal or inclined position, the upper side is called the back; and the under side, the breast. The top side or surface of rafters, and the curved ribs of ceilings or of hand-rails, are called backs.

Backing A Hip-Rafter, Or Rib

The act of forming the upper surface of either in such a manner as to make it range with the backs of the rafters, or ribs, on each side.

Balks, Or Baulks

Small sticks of roughly hewn timber, being the trunks of small trees partially squared. The term usually denotes sticks less than 10 in. square at the but, and tapering a good deal as they approach the other end.

Bar-Posts

Posts fixed in the ground at the sides of a field-gate. They are mortised to receive the movable, horizontal bars.

Basil

The slope or angle of an edge tool, as that on a chisel or plane-iron. The angle is usually 12° for soft and 18p for hard wood.

Batter

A term applied to a wall which is not plumb Or perpendicular on its face, but which slopes from an observer standing in front.

Baulk-Roofing

A term in use when timbers were generally hewn, instead of sawn as at present. It formerly designated a roof framed of baulk-timber, which, being hewn from small trees, could not be formed into square timbers, having an arris i full and square.

Bay

The space intervening between two given portions of the wall or floors of a building.

Bay Of Joists

The joist-ing of a particular portion of a building, as between the posts of a side-wall or the girders of a floor.