C—io.

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Waingaromia River, and here their principal effort to strike oil was made. This bore reached a depth of 1,360 ft., and oil appears to have been found; in fact, through escaping oil and gas the derrick was burned down, despite which there are some who believe that oil was not struck in the South Pacific bore in the valley of the Waingaromia. Be this as it may, the formations here and at the oil-springs near the source of Oil-spring Creek are different, the latter being sandy argillaceous beds of Tertiary date, while the former consists of indurated chalky limestone, white siliceous shales, often of a pink colour with beds of greensand, as shown in the section along Oilspring Creek. Six miles west of the South Pacific borehole is the Minerva borehole, situated in the valley of the Waipaoa River, a mile above the junction of the Mangatu with that river. This also is in Tertiary beds of character similar or identical with those passed through in the South Pacific bore. The bore was sunk to a considerable depth, something approaching 1,000 ft., but no oil was found, and a tenacious pug-clay, it is reported, proved a difficulty that, with others, led to the enterprise being given up. In the case of the Minerva the borehole is within 30 chains of the outcrop of the Cretaceous rocks which appear as a narrow belt crossing east and west the Waipaoa River, and to the eastward are continued along the valley of Oil-spring Creek to the oil-springs, and thence into the valley of the Waitangi, for which see map accompanying. The Cretaceous rocks are continued north along the main range of this part of the Auckland District, but on the coast-line, and for some distance inland, Younger Tertiary beds are met with from the south side of Waipiro Bay to south of Tolago Bay, between which latter place and Gableend Foreland for a short distance in Waitanguru Bay Cretaceous rocks are seen, and again at Whangara, and also, to a limited extent, on the north side of Poverty Bay. North of Waipiro Bay the area between the Waiapu River and the coast-line is wholly occupied by Cretaceous rocks, and west of that river the mountainous region to the Palaeozoic rocks skirting the Bay of Plenty is also formed of Cretaceous rocks. This constitutes the northern area, within which are numerous gas-escapes and evidences of the presence of petroleum. In this region boring for oil was carried on at Rotokaituku, on the west side of the Waiapu Valley. The deepest hole put down by the Southern Cross Company attained a depth of 1,700 ft., but oil in payable quantities was not found, and when last visited by me in 1887 the company had ceased operations, which have not since been resumed. At that time there was a powerful escape of gas from the pipe. The gas had been ignited, and was then burning with a flame some 4 ft. in height, and had done so for some considerable time. In the southern part of the district oil is escaping from Tertiary rocks on Dobbie's Run, seventeen miles north-west of Gisborne. The springs are not powerful, but oil can be collected from one or two pools on the Pangihanga Block at a height of 740 ft. above the sea. Although active operations in search of oil have ceased for a number of years, there have been persistent reports of the discovery of fresh springs and gas-escapes in the Poverty Bay district; and I was led to believe that an important discovery had been made westward of Oil-spring Creek, in the Waipaoa Valley, to examine which I was instructed to visit the district and report what the facts and prospect of such new discoveries might be. I was accompanied from Wellington by Mr. R. Brett, who, in the interest of an English syndicate, is at present interesting himself in the matter of exploring for oil in various parts of the colony. Arrived at Gisborne, as soon as possible a start was made for Karaka, at the junction of the Waipaoa and Waikohu Rivers, and the valley of the latter stream was followed to Pohutu Accommodation-house, at the last crossing of the river on the Gisborne-Opotiki Road, and from that point were carried on yet further to the westward. It was my intention to have followed the Gisborne-Opotiki Road across the mountainran«e into the valley of the Motu River, in order to re-examine the lower beds of the Cretaceous sequence, which on the west side of the range are exposed under the higher calcareous beds, but the weather and the roads were alike execrable, and this part of the trip had to be abandoned. Immediately west of Pohutu and north of the road-line, the Cretaceous rocks appear from under the Tertiary beds that on the south side of the valley continue further to the west, and, the appearance of these along the crest of the anticline being the principal thing sought for, it was by Mr. Brett considered unnecessary to proceed along the road further west ; and I was anxious to see what fresh discoveries had been made in the Waipaoa Valley more to the north. Accordingly we proceeded to the Waingaromia Station, in the Waipaoa Valley, and next day followed the Waingaromia River to the site of the South Pacific borehole ; and passing this, from the Waitangi out-station, in the valley of the river of that name, ascended the range to the west, and at a height of 1,460 ft. reached the oil-springs east of the source of Oil-spring Creek. I anticipated that I was being taken to something new—to a locality I had not before visited, and where the flow of oil was greater than had before been seen by me ; and I certainly expressed surprise at being taken to a place well known to me, and which I had examined as far back as 1874, where oil had been sought for and the search abandoned years ago. After spending some two hours at the oil-springs we proceeded north-west across the ranges to Muir and Finlay's station, at the upper end of the Waipaoa Gorge, and the following day, after examining the valley for a mile and a half above the station, followed the gorge downwards to the junction of the Waipaoa with the Mangatu. It being necessary to return to Gisborne, the next work was an examination of the coast-line to within five miles of Tolago Bay, after which a return was made to the Waipaoa Valley, and the valley of its main tributary, the Mangatu, was examined nearly to its source. At a yet later date the district south of the Waikohu and west of the lower Waipaoa was examined, and the oil-spring-at Dobbie's, on the Pangihanga Block, was visited, which closed the examination made on the present occasion.