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THE NEW ZEALAND GAZETTE.
[No. 77

Regulations for conducting the Survey of Land in New Zealand.

In pursuance and in exercise of the powers and authorities conferred by “The New Zealand Institute of Surveyors and Board of Examiners Act, 1900,” the Surveyors’ Board doth hereby make the following regulations for the guidance of surveyors under “The Land Act, 1892,” “The Native Land Court Act, 1894,” “The Land Transfer Act, 1885,” and their amendments, or under any enactment of the General Assembly of New Zealand relating to or affecting surveys of land, and doth hereby declare that such regulations shall come into force on and the first day of October next.

REGULATIONS.

Interpretation.

1. In these regulations, if not inconsistent with the context,—
   “Surveyor-General” and “Chief Surveyor” mean the persons holding such official positions respectively, or the persons for the time being acting for either of these officers;
   “Surveyor” means a person holding a license from the Surveyors’ Board to execute surveys within the colony, and, in respect of Land Transfer surveys, licensed also by the Surveyor-General in that behalf.

TRIANGULATION.

Major triangulation.

2. The existing so-called major triangulation of this colony partakes of the character of a secondary series, as the base-lines were not required to be measured to a greater accuracy than 3 in. per 100 chains, and the discrepancy in the summation of the angles of a triangle was accepted where it approximated to 20″; but the experience of many years has demonstrated that bases can be measured rapidly and economically with a probable error of less than 1 in. in 100 chains, and the angles with 8 in. to 12 in. theodolites to an average of 5″ in the summation of each triangle.

Base.

3. The site for a base three or more miles in length should be chosen having regard to the facilities it offers for ready and accurate measurement, and for extension and connection with the triangulation. The apparatus and methods to be adopted must conform to those in vogue in the United States Coast and Geodetic Survey (vide United States Coast and Geodetic Survey Report, 1892, Appendix 8, chap. iv; also United States Coast and Geodetic Survey Annual Report, 1901, page 257 et seq.), unless more refined apparatus and more exact methods are approved and authorised. The standard base measuring-tape to be used is of steel or, better, nickel-steel 500 links long, ¼ in. wide, and ¹⁄₅₅ in. thick, the terminals of the 500 links being indicated by fine lines graved on the tape, denoting the precise distance between these lines at a certain tension and at a temperature of 62° Fahr. in terms of the New Zealand Survey Department standard, at the Surveyor-General’s office. A comparator should be set up in the vicinity of the base which must be in exact accord with the above standard, and be used to verify the base-tape both prior to and during the measurements of the base.

Measurement of base.

4. The measurement of the base should be effected as follows: The ends of the tape and straining apparatus should be supported on posts or portable stands, its terminal marks falling over zinc plates fastened to the tops of other posts or stands, the tape being supported at intervals of 50 links by smooth-topped stakes, or on hooks suspended from horizontal arms to same, or to vertical steel rods, all so adjusted as to insure that the tape may be in exact alignment throughout, and that the supports in each stretch of tape when practicable are in one uniform grade from end to end. The extremities of the tape must be attached to proved spring balances or weights and adjusting straining-gear so as to apply a strain of 25 lb., and to bring the zero point of the tape into exact coincidence with a fine line previously drawn upon the zinc plate on the rear post. This being accomplished a fine