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APPENDIX. No. 1. Standard Survey. To J. T. Thomson, Esq., Surveyor-General. Sir, General Survey Office, Wellington, 23rd July, 1879. I have the honour to report on the operations of the Standard Surveyors during the twelve months ended 30th June, and generally on the subject of Standard Survey. Mr. J. W. A. Marchant extended a line of bearings from the station, near Burkes Pass, on through the plains of the Tekapo and Pukaki Lakes to a close on the Geodesical Station Cloud Hill, Ahuriri survey district, Lindis Peak meridian. The difference between the observed and computed convergence of the Timaru and Lindis Peak meridians is 16". Mr. Marchant also laid down a standard chain length at Government Buildings, Wellington, and by means of steel tapes, standardised to this distance, the standards at Auckland, Nelson, Christchurch, and Dunedin, have been compared, with the result that Auckland, Wellington, and Christchurch are practically the same in length, while the chain lengths at Dunedin and Nelson are each very nearly one-eigth (£) of an inch longer. These standards were all laid down at the temperature of 62° Fah. but by different persons and from different brass scales. A comparison of several scales has revealed minute, yet sensible differences in their lengths. The four feet brass scale at the head office, and the 66 feet measured from it at Government Buildings, will be assumed as the standards for the Colony, and all other survey standards will in future be expressed in terms of them. Mr. C. W. Adams began and completed the standard survey of the city of Christchurch, and of the suburban district lying to the west, and comprehended between the Lincoln and Papanui Roads. In Christchurch, lines were run along the street lines near the kerbing and parallel to the building lines, and the intersections are marked at the comers of streets with stone blocks in a manner similar to surveys undertaken in Dunedin and Invercargill some years ago. The original survey of Christchurch had been ranged accurately, hence it became practicable, not only to have the lines parellel to the true building lines, but also rectangular. The finding of lines to satisfy these conditions necessarily occupied more time than the running of arbitrary lines would. But the result is well worthy the trouble, as the arrangement will greatly simplifyjall future reference to the lines ; and as they have been measured with the same care as base lines of trig, surveys, and closed on each other perfectly, there is no reason why the position of every property that is brought under the Land Transfer Act should not be certainly known within a inch or two. The original blocks were laid off on the ground 1111 by 502 links, but as they were Crown granted 1100 by 500 it was impossible in making sub-divisions, to get the aggregate distances to agree with the total as Crown granted. Now that the facts are laid bare, there need be no further perplexity. With very ordinary care all risk of guaranteeing titles to encroachments should cease. A similar survey is in progress for the City of Auckland, where it is especially necessary, on account of original plans having been destroyed by fire, and the impossibility of compiling a plan from deeds extant. These town standard surveys may reveal discrepancies in recognised boundaries, but they do not affect to alter or correct them. Their sole object is to afford a sure basis of reference for the Land Transfer surveys. The trigonometrical survey becomes of little account as a basis for checking surveys in a town as the streets get built up. Besides, the trig, points are too far between, and would never do as starting and closing points for surveys of frontages, that may be worth a hundred or more pounds per foot. Each town standard survey is of course connected with the trig, survey, and the bearings of lines are all on true meridian. In Taranaki, the meridian line, run through the forest from Waitara to the Waimate Plains, was completed early in the season. It is forty-two miles long, and was run with very great care and accuracy. Mr. Humphries determined the true meridian at its south end astronomically, and on comparison with the line as marked on the ground, there was an almost perfect agreement, the discrepancy amounting to only 4". The instrument employed on this work is an excellent seven inch Transit Theodolite by Troughton and Simms. From the meridian line a perpendicular has been run for ten miles eastward into the forest. The natives have tampered with the marks on a portion of the meridian line, but to what extent is not yet known. An inland line of bearings run from hill-top to hill-top, which had to be cleared, has also been completed. The close in this case was not good b tug 1' 26" discrepant. In Marlborough, Mr. A. D. Wilson has completed the field work of ;i major and minor triangulation from a measured base of over two miles in the Wairau Plains near Ren wick. The chain of triangles extend from the initial station of meridional circuit, Goulter Hill, Wairau, up the Kaituna and Pelorus valleys to the crest of the hills overlooking Nelson. One or two triangles from the Nelson side will effect connection with the Messrs. Carkeek's triangulation, Waimea. Mr. Wilson is now engaged on the trig, and topographical plans of his work. The triangles cover 156,000 acres. In Westland, Mr. J. G. Roberts has established standard bearings south from Ko-i-terangi to Abut Head. As this country is difficult to get about in, and there is no great urgency for standard bearings, a major triangulation with subsidiary stations is being carried on simultaneously. The country south from Abut Head to Jackson's Bay,'_one or two of the interior valleys of Nelson, and the King country in the North Island are the only parts of the Colony remaining, over which it is desirable to extend standard bearings when there is opportunity. The extention of standard bearings may therefore be said to be completed for a time. Summarising the results of former seasons' work, there are twenty-eight meridional circuits, subdivided into survey districts, of as near as may be, 12J miles square or 100,000 acres. Each survey