DEFINITIONS OF HINDS OF MASONRY.* Stone masonry is classified (1) according to the degree of the finish of the face of the stones, as quarry-faced, pitch-faced, and cut-stone; (2) according to whether the horizontal joints are more or less continuous, as range, broken range, and random; and (3) according to the care employed in dressing the beds and joints, as ashlar, squared-stone, and rubble.
Pitch-faced Masonry. That in which the face edges of the beds are pitched to a right line—see Fig. 68. Notice that the outer edge of a horizontal joint of pitch-faced masonry is straight, while in quarry-faced it is not.
Cut-stone Masonry. That in which the face of the stone is finished by any one of the methods described in § 545-46, as rough-pointed, fine-pointed, crandalled, axed, bush-hammered, rubbed. etc.
Classification According to Conti nuity of Courses. Range. Masonry in which a course is of the same thickness throughout—see Fig. 69.
Broken Range. Masonry in which a course is not continuous throughout—see Fig. 70.
Random. Masonry which is not laid in courses at all—see Fig. 71. Random masonry is sometimes designated as one-against-two or two-against-three, the first term indicating that there is one stone on one side of a vertical joint and two on the other, and similarly for the second term.
Any one of these three terms may be employed to designate the coursing of either ashlar (§ 551) or square-stone masonry (§ 552), but can not be applied to rubble (§ 553).
ashlar apparently means large, square blocks; but practice seems to have made it synonymous with "cut-stone," and this secondary meaning has been retained for convenience. The coursing of ashlar is described by prefixing range, broken range, or random; and the finish of the face is described by prefixing a name to designate the finish of the face of the stone (see § 545-46) of which the masonry is composed.
Small Ashlar. Cut-stone masonry in which the stones are less' than one foot thick. The term is not often used.
Rough Ashlar. A term sometimes given to squared-stone masonry (5 552), either quarry-faced or pitch-faced, when laid as range work; but it is more logical and more expressive to call such work range squared-stone masonry.
Dimension Stone. Cut stone, all of whose dimensions have been fixed in advance. "If the specifications for ashlar masonry are so written as to prescribe the dimensions to be used, it will not be necessary to make a new class for masonry composed of dimension stones." Squared-stone Masonry. Work in which the stones are roughly squared and roughly dressed on beds and joints (§ 544). The distinction between squared-stone masonry and ashlar (I 551) lies in the degree of closeness of the joints. According to the Report of the Committee of the American Society of Civil Engineers, "when the dressing on the joints is such that the distance between the general planes of the surface of adjoining stones is one half inch or more, the stones properly belong to this class"; nevertheless, such masonry is often classed as ashlar or cut-stone masonry.
Rubble Masonry. Masonry composed of unsquared stone ( 543): Uncoursed Rubble. Masonry composed of unsquared stones laid without any attempt at regular courses— see Fig. 72.
Unsquared-stone ma sonry which is leveled off at specified heights to an approximately horiz.,ntal surface. It may be specified that the stone shall be roughly shaped with the hammer, so as to fit approximately—see Fig. 73.