The Coconino sun., 1916-04-07

(A) inch to the foot. f. All walks at alley crossing shall be constructed so as to give free in- gress and egress to the alley and flush with the top of the adjoining walks. g. Openings for drainage shall be left under all alley crossings where necessary; the sizes of such openings to be decided by the Town Engineer
 FOUNDATIONS:
 All materials excavated in con structing the foundations shall be classified as earth, loose rock and solid rock, and the prices bid for these classes of excavation, and for the em- bankment necessary to bring the side walk foundation to the proper sub grade, shall apply to all work neces- sary for the proper grading of the foundations.
 Where considered necessary by the Town Engineer, some points mate rial, such as gravel or cinders, shall be used to bring the foundation up to the proper sub-grade, and proper drainage provided for the same.
 All foundations shall be cleaned of all trash and vegetable matter, and thoroughly rolled or tamped and dampened before placing any concrete upon the same.
 RETAINING WALLS:
 Where considered necessary by the Town Engineer, stone or concrete retaining wall shall be built to retain the sidewalk foundation.
 CEMENT
 The cement used shall be Portland cement and must conform to the re- quirements and be subject to the tests as set forth in Specification No. IA, of the Town of Flagstaff.
 FINE AGGREGATE:
 Fine aggregate shall consist of sand or screenings from hard, durable crushed rock or gravel consisting of quartzite grains or other equally hard material, graded from fine to coarse, with the coarse particles predominant ing and passing, when dry, screen having one-quarter (A) inch open ings. It shall be clean, free from dust, vegetable or other deleterious matter, and all fine aggregate con taining more than five (5) per cent clay or loam shall be washed before using.
 COARSE AGGREGATE:
 Coarse aggregate shall consist of clean, hard, durable crushed rock or gravel, graded to size, free from dust, loam, vegetable or other deleterious matter, and of such sizes as to pass a two and one-half (2h) inch round opening and to be retained on screen having one-quarter (h) inch open ings.
 NATURAL MIXED AGGREGATE
 Natural mixed aggregate shall not be used as it comes from deposits, but shall be screened and used as speci- fled.
 WATER:
 Water shall be clean, free from acid, oil, alkali or vegetable matter.
 FORMS:
 Forms shall be we'll built substantial, unyielding and properly braced and shall conform to the lines given by the Town Engineer.
 Lumber once used in forms shall be cleaned before being used again.
 CONSTRUCTION:
 The concrete walks shall be two coat work placed as follows: On the foundation, finished as above speci- fled, and four (4) inches below and parallel to the finished surface of the proposed walk, shall be placed a con crete base three (3) inches thick, con sisting of the following materials:
 Portland cement-one part by vol ume.
 Fine aggregate-three parts by vol ume.
 Coarse aggregate-four parts by volume.
 a sack of cement weighing ninety four (94) pounds net shall be con sidered as having a volume of one CD cubic foot.
 The densest possible mixture of the aggregate making up the concrete is desirable, and the proportions of the aggregate may be varied by order of the Superintendent of Streets when he deems it necessary, but in no case shall the total aggregate be more than seven CD parts to one CD part cement by volume.
 After the base has been placed and worked to an even grade, and before it has taken it's initial set, there shall