27

(J—la

Amended Results of Measurement— continued.

J. Lanqmuir, 27th February, 1912. Inspecting Surveyor.

ADJUSTMENT OF WAIRARAPA BASE-NET. [By C. E. Adams, M.Sc, F.R.A.S., Chief Computer.] During the year Mr. 11. E. Qirdleetone, assistant surveyor, lias observed at, the following trigonometrical stations in the Wellington District, using a 10-in. Everest theodolite with three verniers reading to 10": Rangitumau, Uimutaka, Wainui. Kapakapanui, Taungata, Puketoi, Arawaru, Wharite, Moutere, Raetihi, Raetihi Hill, Kawai-o-tawaki. and \\ aipuna. The angles have been taken out from the field-books and tin , angular errors of the triangles ascertained. Mr. .J. Langmuir, Inspector of Surveys, has slightly amended the lengths of the measurements of the Wairarapa baseline, the alteration being due to a small constant error in the correction for mean tension. An extract from the field-book shows a portion of the observations of the horizontal angles at geodetic station, Arawaru. The observations are taken in four sets : set lis taken face right and in the clockwise direction : set 2is taken lace left and in the reverse direction. These two sets give one complete observation as shown at No. I on the abstract of horizontal angles. In a similar way the other seven observations are taken, and the mean of the eight observations is adopted as the observed angle. Opaki Circuit, Arawaru Geodetic Station. 12th August, 1911, 9.30-10.40 a.m. 10 in. Everest instrument. Field-book No. 21, page 27. Origin : Puketoi, 103° 38' 026". Observer : H. E. Girdlestone. fooe. Ventim. Pnketoi. R»n K itunmii. Momt Dundee. Return. DeMriptkmaf B*»tton» and o/» O / * a t m o / * f A in:! 12 20 166 12 45 212 II I.". LO3 12 20 Righl .. -i B 42 16 12 40 II OB 42 20 C 42 10 12 46 II IT> 42 10 f O L3B 4.'. (Hi LO6 16 30 242 14 00 133 45 06 Left .. iJ B 45 (M) If) 30 14 or) 4.-> 00 A 4."i lo 15 36 14 0") 45 06 (Cold south-east breeze; B L 63 47 (Hi 226 17 :iO 272 16 .V> l«:{ 4tt .■>;> ' atmosphere very dear. Left .. J (; 4« 50 17 2.-> Mi 00 40 60 [ A 47 00 17 :i0 Lβ 00 47 00 f A \m 4!i :so 266 19 66 :(02 18 30 lie* 4!i :to ItK'ht ..J B 4!) 35 ! 20 00 18 4(1 19 X"> [ 0 4!) 25 20 00 IS 26 4(1 2"> 71 15 197 05 , 59 L 5 71 15 .Means .. 103 45 sfi-2 IHK lt> 25-4 212 14 s(i-2; 103 4i 56-2

= i Measure- Individual w , htll °J nS Measurements. W "* ht "- — Weighted Means. «%%»%* Length at Sealevel. Remarks. Links. Links. Links. 51628-9154, 0-4142 5896-4425 5896-4426 5896-4470 5896-4403 Links. 51628-5012, Brought forward. S I 5896-4425 L 2 5896-4426 1 3 5896-4470 I 4 5896-4403 I 4 1-7724 5896-4431 0 0-0282 5896-4149 0 n i 2 8 4 7251-8374 7251-8342 7251-8229 7251-8014 I I 1 I 7251-8374 7251-8342 7251-8229 7251-8014 Total amended length of line. 4 3-2959 4 7251-8239 S 0-0732 64777-1825 0-5156 7251- 7507 „ 64776-6668 „ 72. r )l-7507 8 64776-6668,, ' ■ ■ * ■ " ' — ' * r T_* M. T r*_p I Auxiliary Base. I 2 3 4 11463-7583 11463-7533 L1463-7044 11463-7150 4 45854-9310 Amended length of Auxiliary Base. 114H3-7327 5 0-04384 II4H3-6889,