MASONRY DEFINITIONS. 267 



Portland Cement. This term shall be applied to the finely pulverized product resulting 

 fiom the r.tlcin.ition to incipient fusion of an intimate mixture of properly proportioned argif- 

 l.uvous and r.ih .in MUS materials, and to which no addition greater than 3 per cent has been made 

 .lent t<> '-.ill inution. 



Natural Cement. This term shall be applied to the finely pulverized product resulting from 

 the calcination of an argillaceous limestone at a temperature only sufficient to drive off the carbonic 

 acid gas. 



Puzzolan Cement, as Made in North America. An intimate mixture obtained by finely 

 pulverizing together granulated basic blast furnace slag and slacked lime. 



COURSES AND BOND. 



Coursed. Laid with continuous bed joints. 



Broken Coursed. Laid with parallel, but not continuous, bed joints. 



Uncoursed. Laid without regard to courses. 



English Bond. That disposition of bricks in a structure in which each course is composed 

 entirely of headers or of stretchers. 



Flemish Bond. That disposition of bricks in a structure in which the headers and stretchers 

 alternate in each course, the header being so placed that the outer end lies on the middle of a 

 stretcher in the course below. 



DRESSING. 



Dressing. The finish given to the surface of stones or to concrete. 



Smooth. Having surface, the variations of which do not exceed one-sixteenth inch from the 

 pitch line. 



Fine Pointed. Having irregular surface, the variations of which do not exceed one-quarter 

 inch from the pitch line. 



Rough Pointed. Having irregular surface, the variations of which do not exceed one-half 

 inch from the pitch line. 



Scabbled. Having irregular surface, the variations of which do not exceed three-quarters 

 inch from the pitch line. 



Rock-Faced. Presenting irregular projecting face, without indications of tool mark. 



DESCRIPTIVE WORDS. 



Abutment. A supporting wall carrying the end of a bridge or span and sustaining the pressure 

 of the abutting earth. The abutment of an arch is commonly called a bench wall. 



Arris. The external edge formed by two surfaces, whether plain or curved, meeting each 

 other. 



Ashlar. A squared or cut block of stone with rectangular dimensions. 



Backing. That portion of a masonry wall or structure built in the rear of the face. It must 

 be attached to the face and bonded with it. It is usually of a cheaper grade of work than the face. 



Batter. The slope or inclination of the face or back of a wall from a vertical line. 



Bed. The top and bottom of a stone. (See Course Bed; Natural Bed; Foundation Bed.) 



Bed Joint. A horizontal joint, or one perpendicular to the line of pressure. 



Bench Wall. The abutment from which an arch springs. 



Bond. The mechanical disposition of stone, brick or other building blocks by overlapping 

 to break joints. 



Build. A vertical joint. 



Centering. A temporary support used in arch construction. (Also called centers.) 



Clamp. An instrument for lifting stone so designed that its grip on the surface of the stone 

 is increased as the load is applied. That portion engaging the stone is of wood attached to a steel 

 shoe, which in turn is hinged to the shank of the clamp in such a manner as to adjust itself to the 

 surface of the body lifted. 



Coping. A top course of stone or concrete, generally slightly projecting, to shelter the masonry 

 from the weather, or to distribute the pressure from exterior loading. 



Course. Each separate layer in stone, concrete or brick masonry. 



Course Bed. Stone, brick or other building material In position, upon which other material 

 is to be laid. 



Cramps. Bars of iron having the ends turned at right angles to the body of the bar which 

 enter holes in the upper side of adjacent stones. 



Culvert. A small covered passage for water under a roadway or embankment. 



Dimension Stone. (i) A block of stone cut to specified dimensions. 



Dimension Stone. (2) Large blocks of stone quarried to be cut to specified dimensions. 



