2738
THE NEW ZEALAND GAZETTE.
[No. 77

ROADS.

Grades, curves.

57. Main roads, where practicable, should not have a steeper grade than 1 in 20, or a sharper curve than 66 ft. radius when formed. District roads to be laid off with grades not exceeding 1 in 15, and having no curve less than 33 ft. radius when formed. The grades in cross-roads should not exceed 1 in 12.

Widths.

58. All roads, as far as practicable, must be on the sunny sides of hills and spurs, graded on the best lines obtainable, and be reserved to a width of not less than 66 ft. In broken country, and where heavy cuttings and banks occur, the width of a road must be increased where necessary.

Grading.

59. In grading roads along sideling ground, when the difference in level between the terminal points will permit, it is advisable while running round sharp curves and gullies either to keep the line level, or to ease the grade where required, to allow for through cuttings and banks being made at some future time to straighten and shorten the road without unduly increasing the grade, and where necessary sufficient land should be reserved to allow of this being done. In fact, wherever practicable, the grade on the finished road should be eased at sharp turns. In certain cases longitudinal and cross sections will be necessary, for which special instructions will be given. All gradients steeper than 1 in 20 should be written on the plan, with arrows indicating the direction of fall. Grade-lines should be marked with stakes not less than 2 in. diameter at intervals of a chain, more or less, according to the ground.

Pegging and width.

60. In level or undulating country the opposite road-angles must all be pegged; but in rough hilly country, where land is of little value and the traverse-lines short and intricate, the outside pegs at each angle may be dispensed with, and the road shown by straight lines adjacent to conveniently situated traverse-pegs, the lines forming the sides of the road to be calculated, and such side lines to be pegged. The lines bounding the road in such cases need not be parallel, but must not approach nearer than 50 links to the centre of the road, nor be distant therefrom more than 150 links without permission of the Chief Surveyor.

Delineation.

61. In whatsoever manner the side lines of the road are laid off, the bearings and lengths thereof must be computed and shown on the map, and also their positions in relation to the traverse-stations, especially as regards section-corners.

Reference-tubes.

62. At distances of about a mile apart a group of three iron ¾ in. reference tubes, 2 ft. 6 in. in length, are to be inserted in positions not likely to be disturbed, and be visible from each other, and, where possible, from a trig. station.

Railway-crossings.

63. In cases where roads abut upon or cross railway-lines the surveyor must communicate with the District Engineer of Railways on the subject, with the view of arranging for suitable crossings.

GENERAL.

Pegging and marking.

64. All pegs are to be of sawn or split and dressed heart of totara, kowhai, blue-gum, kauri, matai, puriri, or hinau, 2½ in. by 2½ in., or, if not procurable, 3 in. by 2 in., and 2 ft. long, driven not less than 18 in. into the ground, a hole having first been made with an iron jumper. In special circumstances the length of peg must be varied—thus, in loose sand or in swamp pegs may be used 3 ft. or more in length; while on public roads, railways, and centre road traverse, where pegs must be driven flush with the surface, 18 in. pegs or 8 in. iron spikes may be used. The front pegs of sections must have the numbers of the sections