H.—l

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puted through the network of triangles; also by comparing the observed and computed convergence of meridians. The results of these tests were very satisfactory, considering the means and the instruments used; and they do high credit to the skill and care of Mr. McKerrow, by whom all the original observations for latitude and true azimuth were made. The various circuits were now, with a little necessary humouring at the common edges, brought together on a geographical projection on the scale of eight miles to an inch, and the details were filled in from the topographical maps as far as finished and the original reconnaissance surveys, thus furnishing a pretty good map of the province, which was lithographed and published in 1871. In this map, a new edition of which with later details is being prepared, the Admiralty longitudes of Port Chalmers and the Bluff have been taken as fundamental. Summary of Progress. Acres. Section surveyed, trustworthy .. .. .. .. 2,800,000 Triangulated and topographically surveyed only .. .. 4,200,000 Reconnaisance only .. .. .. .. .. 4,000,000 Unsurveycd ..' .. .. .. .. .. 5,038,400 Total area of Otago .. .. 16,038,400

lII.—STTMMAKY. Reviewing what has been written thus far on the progress and state of the various surveys, it appears that, out of the 66,961,160 acres which make up the area of the two islands, 1 about 20,631,200 acres, 2 or three-tenths of the whole, have been covered with triangles trustworthily observed; 4,730,900 acres have been accurately and 6,405,500 acres 3 more or less inaccurately section-surveyed. Of Native claims, the surveyed total 4 amounts to about 4,689,787 acres, most of it needing some adjustment before it can be accepted as correct. The topographical and block surveys comprise 7,962,400 acres, nearly two-thirds of it good, the rest of doubtful quality; and the remaining 43,172,573 acres are either untouched or have been surveyed by reconnaissance only. The point to be now considered is, how far these materials are or can be made available for accurate cadastral or topographical maps. To take, in the first place, the triangulations. They, as has been shown, are spread in six or seven detached pieces over parts of the Provinces of Auckland, Hawke's Bay, Wellington, Canterbury, and Otago. In the various parts the base-lines and angles were measured with commendable care. A good deal of pains was taken in determining geographical positions. Details generally were carried out in a correct and orderly manner, and the records have been carefully kept. In short, high praise is due to the officers who have conducted these operations. But the work has been done piecemeal, and each piece in a different way. In its present state it rests on a multiplicity of bases and standards, and on eight or nine separate determinations of true meridian and geographical position—some of them doubtless good, others more or less imperfect according to the means and methods employed. In Otago alone there have been already at least seventy base-lines and seventy small triangulations, and there are many yet to follow. You have a number of disjointed details, of good enough quality in themselves, but as yet no means of piecing them together. To put them to their full uses, it will be necessary to bring the whole within the grasp of one exact and comprehensive system, and to refer them to a single standard of length and a single starting point. If this be done—and it can be done—the small errors and inconsistencies which must undoubtedly have crept into the present systems will be eliminated, and every part will be welded into a compact and homogeneous whole. The double purpose will also have been fulfilled of making all the trigonometrical work that has been done available both for cadastral record plans, and for the construction of accurate geographical maps of the country. In this way, hardly anything need be wasted. The state of the section surveys, however, is much less encouraging. Piecemeal work and want of unity of plan have here been introduced wholesale. Ten different departments have been at work in as many different parts of the colony, and following systems so various that scarcely any two are exactly alike. Some of these systems have been good and others bad. Out of the 11,136,400 acres returned as finished under this head, 4,730,900 acres, mainly in the triangulated area, may be said to come up to that standard of accuracy which fits them to form the kind of map required by the country —that is to say, a cadastral map on the correctness of which all men may agree, and which will give safety and value to Crown grants, and protect individuals from litigation, and Government from the risks involved in the issue of titles under the Land Transfer Act. But there is an enormous arrear of faulty work. Of the remaining 6,405,500 acres, a very large proportion has been inaccurately done, and is next to valueless for the purposes named j the whole of it must sooner or later be submitted to tedious and costly revision, 1 According to the Report of the Conference of Chief Surveyors, 1873. See also the Abstract at the end of this Report. 2 These figures do not include the small imperfect provincial triangulations in Marlborough, Westland, and Hawke's Bay, nor the 1,200,000 acres in Canterbury which need revision. 3 Including the Confiscated lands in Auckland. ■•Excluding 21,760 acres in Canterbury and Otago.