C.—lA

II

cost of the whole operation, both trigonometrical and topographical, will not much exceed a penny per acre ; and it is but due to the surveyors employed, Messrs. L. Cussen, H. M. Skeet, A. D. Wilson and his assistant W. H. Dunnage, John and Joseph Annabell, and Mr. Thorpe, to acknowledge their energy and devotion in a most arduous work, necessarily executed under much privation, and often with no small risk of life in the encounter with flooded rivers and the ascent of the lofty snow-capped Ruapehu. Mr. Cussen supplies a valuable report (see Appendix No. 2) on the soil, forests, and resources of the country triangulated by him; also his notes on Ruapehu and Lake Taupo, which are especially interesting at the present time on account of the volcanic eruption at Tarawera on the 10th June last. It has long been known that there was on the summit of Ruapehu a small lake of hot water girdled in everlasting snows; but hitherto little credence has been given to any assertion as to steam issuing from it, and if it did occur it certainly has been for many years past a very rare event. However, during the months of April and May, steam was frequently seen to issue. Thus, Mr. Cussen states that early in April he noticed on several days a column of steam rising high above the mountain-top ; and Mr. Wilson states : "When observing angles at Pipipi on the morning of the 15th May I noticed a column of steam about 300 ft. high ascending from Ruapehu, and since then I have occasionally seen small quantities of steam issuing from it." Mr. Dunnage's interesting report in the appendix is a confirmation of the fact of steam issuing from Ruapehu, he having been on the summit of the mountain when he saw the hot lake and the steam rising from it. In the Proceedings of the Royal Geographical Society for May, 1886, at page 335, there is an account of the ascent of the volcano of Popocatepetl, Mexico (altitude 18,000 ft.), and of the crater, from which steam and sulphur-fumes issue amid the snow, as in the case of Ruapehu. The soundings of Lake Taupo, which are given on plan in appendix, are a valuable contribution in aid of forming a correct theory as to the origin of the lake-basin. The uniformity of depth —generally about 400 ft.—the shape of the lake, and its surroundings, all so different from the long, narrow, deep lakes and West Coast sounds of the Middle Island, dispel at once any application of the theory of glacial action, which explains the gradation of soundings, moraine deposits, and other characteristics of these lakes and sounds, so well. Lake Taupo, by comparison, may be regarded as a great shallow natural reservoir on the line of the Waikato River, occupying a hollow, formed partly, it may be, by old volcanic craters and subsidence, and partly impounded by a rim of pumice, rhyolite, and other products of volcanic action. Were the lake to run dry, its bed would be a compact level plain of an area of 241 square miles, at an elevation of about 800 ft, above the sea. The great lakes of Otago, in the Middle Island, already referred to—viz., Te Anau, Manipouri, Wakatipu, Wanaka, and Hawea—cover an aggregate area of 419 square miles. They are long and narrow, occupying the old glacier-beds in the mountain-valleys, and of great depth—over a thousand feet at the deepest. They could not be run dry, as their beds are below the level of the sea. The sudden rise and fall of the waters of Lake Taupo on the 28th August, 1883, referred to by Mr. Cussen as noted by Major Scannell, and also recorded by Dr. Hector in Vol. XVI., Proceedings of New Zealand Institute, page 536, is a striking testimony to the terrible force of the volcanic eruption at Krakatoa, Straits of Sunda, which occurred on the 27th August, about twenty-two hours before the wave of pulsation reached Taupo, a distance of about five thousand miles. It is recorded that in the great earthquake of Lisbon in 1755 the waters of Loch Lomond and other lochs in Scotland rose and fell similarly—the distance in this case, about thirteen hundred miles. The great lakes in America were similarly affected by the Lisbon earthquake. The only other triangulation of note in the North Island is the completion by Mr. James Baber of a series of triangles over the Waiapu and East Cape District. This work was stopped by Native obstruction two years ago, and was only successfully resumed this season, and closed on the Opotiki coastal triangulation of Mr. C. A. Baker. In the Middle Island, Mr. F. S. Smith, District Surveyor, and assistants, Messrs. F. A. Thompson and L. Paske, were engaged in the trigonometrical and topographical survey of the high back-country at the head-waters of the Clarence and Waiau-ua Rivers, and along the eastern side of the main range, and also on the road and sectional surveys and runboundaries. They have booked a very good season's work, which is now in process of computation and mapping. A most grievous disaster befel this survey-party on the 9th June