C—3.

Auckland Trigonometrical and Chain Closures, 1881-82.

Note. —The above shows a fair average of the closures ; it, of course, only includes a few of them.

SCHEDULE A.—WELLINGTON. Comparison of Bases, taking Waipakura Base, measured by Mr. John Annabell, as Standard for Comparison, equal 16,128·02 links.

A mean correction of I'B3 links per mile was applied to the old Wellington provincial triangulation distances to reduce them to the new Wellington City standard survey measurements. This nearly agrees with the results obtained by major triangulation, which showed that the Wellington distances were short by T56 per mile.

Comparison of Wellington District Triangulations.

33

Trigonometrical lhain. Surveyors. Number of Closures. Mean Differences of Bearing of Closures. Mean Ratio of Diff-rence of Closure per Mile. Number of Closures. Number of Traverse Lines. Total Length of Traverse Lines. Mean Ratio of Error of Closure. i. Weetman 5. C. Goldsmith j. Cussen p. Simpson P. H. Edgecumbe i. Newmann 5. Lambert '. E. Cheal V. J. Parris 3-. A. Martin 5. H.Hardy I. M. Smith '.I.Philips X Stevens '. Hannah I. A. Martin L.M.Ross 6 4 22 5 13" 4" ll"-3 19" Iks. ■53 •50 ■50 11 6 380 67 37-4 11-9 Iks. 1-6 4 3 11" 1 3 5 10 6 10 5 6 9 3 9 7 1 128 224 102 276 95 46 83 15-6 41-7 11-7 15-7 22-4 7-1 13-4 10-2 41-5 16-2 3-25 1-4 1-36 IT 5-28 2 2-5 2-2 0-4 2-35 2 01 "i 0-44 2 6 2 10" 0-8 1-9 0-6 130 16 7" fi 4 iio 48 16 6-9 6-5 2 Means and totals j 54 54 75"-3 10"-7 9-27 1-03 98 98 1,705 1,705 265-95 265-95 28-79 1-92

Base. Length. By Whom Measured. ?he " Westmere" (computed from Waipakura, = 8,621-00) 8,621-53 8,623-4 diff. P87 Mr. John Annabell and the Chief Surveyor, Mr. J. Mitchell. ?he"Okirae" = P74 per mile. 10,835-24 10,836-00 diff, 0-76 Mr. John Annabell. Computed from Waipakura. ?he"TeRuanui" ... = 0'56 per mile. 4,314-4 4,314-6 diff. 0-2 Mr. D. H. Munro, computed from Waipakura. = 0-39 per mile.

Surveyor and Survey District, a £ & 3 fc o a £ H 2 CO Side. Bearings. Distances. P S 0 " Remarks. O / // Iks. 28,350-1 53-1 diff. " 3-0 Iks. G. A. Northcroft, Puketoi. (Comparison with original work by A. Dundas and J. Kelleher.) 10" K, Rakonui, to J, Butters ... Mr. Northcroft's lay within limits of original triangulation. Puketoi, to K, Rakonui 292 15 7 15 10 0-9 I, Table, to J, Castle Ridge diff. 3 23,621-0 25-2 diff. ' 4-2 1-4