DICTIONARY OF MASONRY TERMS The following definitions are in common use in the mason's and stonecutter's trade: Abutment—A supporting wall carrying the end of a bridge or span and sustaining the pres sure of the abutting earth.
Arris—The external edge formed by two sur faces of stone, whether plane or curved. Ashlar—A squared or cut block of stone, usually with rectangular dimension.
upper curve of a right section of an arch, perpendicular to the axis.
Face—The exposed surface of a stone, in eleva tion.
Footing—A projecting bottom course.
Foundation—That portion of a structure, usually below the surface of the ground, which dis tributes the pressure upon its support. Also applied to the natural support itself.
Foundation-Bed—The surface upon which a structure rests.
Grout—A thin mortar either poured or applied with a brush.
Header—A stone which has its greatest length at right angles to the face of the wall, and which bonds the face stones to the backing.
Intrados—The lower curve of a right section of an arch, perpendicular to the axis.
Joint—The narrow space between adjacent stones, bricks, or other building blocks usually filled with mortar.
used to carry and distribute the weight of an arch to ribs or centering during construction. Also used to designate the strips temporarily supporting soft material, as outside the timbering of a tunnel.
four-piece steel instrument used in lifting stone. The lewis, when in use, is keyed into a triangular hole cut in the stone.
Lock—Any special device or method of con struction used to secure the bonding.
Paving—Regularly placed stones or bricks forming a floor.
(2) All stones shall be dressed for laying on natural beds. For granite and marble, this pre caution is usually unimportant. With sandstone it must always be observed.
(3) The sand and cement should preferably be mixed dry (in no case should the cement be wet before the sand) ; then water added, and the whole remixed until the entire mass of mor tar is thoroughly homogeneous and leaves the hoe or shovel clean when the latter is drawn from it.
(4) All stones shall be laid on natural beds. Each stone shall be settled into place in a full bed of mortar. That is to say, no stone shall be allowed to touch another stone, but must have a complete coating of mortar around it. If this precaution be not observed, the imposed weight will cause unequal pressure on the stones touch ing each other; and rupture may occur from this cause.