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Prospects op Gas and Oil. The Blairlogie gas-vent has long been known, and as a result of this work it is now known that it is not related to any favourable oil or gas structure. The source of the gas is the basal Cretaceous conglomerate which rests unconformable on the greywacke. This is exposed in the new cutting on the road and was followed south to where it pinched out, and north for two and a half miles. A mile and a quarter north-east of the road it was found to contain a slicken-sided, black, glossy, argillaceous matrix with Belemnites and Inoceramus, and to smell fairly strongly of oil. It is not an oil-sand into which oil has migrated, but is evidently a foul bottom conglomerate that contains enough organic material to yield a smell of petroleum. Samples of it broken under water did not give a scum. This bed was not seen at the gas-vent, the only rock visible there being a streaky clay, evidently a pug, but it crops out 10 chains east of the vent and evidently dips west below it. When crushed in the faulting this conglomerate, it is thought, is producing the gas that escapes at the vent. THE LIMESTONE DEPOSITS OF BLOCK I, KIDNAPPERS CROWN GRANT DISTRICT, AND SECTION 2k, BLOCK IV, KIDNAPPERS SURVEY DISTRICT. (By M. Onqley.) The limestone deposit is on a property of 13 acres in Block I, Kidnappers Crown Grant District, and part of Section 2k in Block IV, Kidnappers Survey District, about a quarter of a mile east of Tukituki River, at the junction of the Elsthorpe and Waimarama roads. It lies north of the road between the road and a small stream that flows west, a quarter mile north, into the Tukituki. South of the stream are three terrace-like flats 10 ft., 60 ft., and 130 ft. above it, and above the top flat rise the slopes of the hills. Mudstone crops out north of the stream, but parts of the bed of the stream and the three terrace fronts are calcareous sinter. The 10 ft. and 60 ft. flats have sinter appearing through them in places, and their flat, even form indicates that they are uniform and composed of sinter. No work to verify this has been done, as no importance is attached to them. The front of the upper terrace is sinter from end to end—that is, for 15 ch. to 16 ch. and 50 ft. to 120 ft. high. At a cave 20 ft. below the surface a tunnel penetrates 50 ft. and is through sinter all the way. At the quarry a cave extends 20 ft. into the sinter about 50 ft. below the surface. At the surface the holes sunk with a crowbar struck sinter 3 ft. to 5 ft. down at points indicated on the sketch and paced as 25 ft., 50 ft., 50 ft., 75 ft., and 100 ft. back from the terrace-front. The thickness of the sinter below the holes is not known. The evidence set out indicates a big deposit of sinter and suggests that all the terraces consist of sinter from the surface down to stream-level. This has not been tested and cannot be relied on and should not be used in estimating the quantity, for it is well known that many sinter deposits are in the form of thin crusts or are merely skins over rock. It would be simple to sink shafts or bore from the top terrace or to put in adits from the low levels and so secure data to allow the quantity to be measured. Half a dozen low-level adits spaced along the high terrace front would provide valuable evidence, and could be quickly and cheaply driven. I understand that the sinter in sight is considered sufficient for a generation, and that it is planned to go ahead with the quarrying. This certainly looks all right and will probably turn out successful, but it is taking an unnecessary risk that can be avoided cheaply. The stone is like nearly all sinters, slightly brownish in colour. Much of it is blanket formation or like curtains, much is in thin branching stems, and parts of it are stalactitic and stalagmitic. It is all chemically deposited sinter, and like most such sinters will probably be 99 per cent, calcium carbonate. I saw no impure or mixed sandy or earthy deposits and consider it all chemically deposited high-grade sinter. Altogether it is a surprisingly big deposit of high-grade sinter. AURIFEROUS DEPOSITS AT PORT MOLYNEUX. (By J. Healy.) A gold claim was inspected at Port Molyneux on Section 1, Block 11, South Molyneux district, where auriferous deposits are being worked by the owner, Mr. Tilson. The claim abuts on the main road running along the sea-coast from Port Molyneux, and the present workings are some 150 yd. back from the road, on rising ground immediately north of a small stream. The richest wash, a blue-grey gravel of unknown but probably inconsiderable thickness, rests on a solid rock. Above it is 4 ft. to 5 ft. of considerably oxidized conglomerate consisting mainly of pebbles up to 2 in. in diameter, though occasional boulders reach a foot; the matrix is blacksand, which is also found as lensoid pockets throughout the bed. This wash passes up into a 4 ft. layer of finely bedded blacksand showing cross-bedding in places, above which is a light-coloured sand stained slightly brown. The blacksand and underlying conglomerate are auriferous, all the gold being very fine. The upper surface of the sand is fairly level and about 20 ft. above sea-level, the overburden being a stiff, brown clay very similar to the loess from the Waikaka district. Its thickness increases as the slopes rise landward, where a terrace 80 ft. to 90 ft. above sea-level extends for a short distance to the south and south-west. Two hundred yards north-east of the workings is a rock-platform 30 ft. above sea-level, but half a mile to the south the rock rises to a much greater height, as a ridge which stretches away to the north-west and defines the probable boundary of the auriferous deposit, though its exact extent is obscured by the thick clay on top. Solid rock is found in many places at low level, and apparently forms a fairly uniform surface on which the gravel rests. The gold has been derived from the ancient Molyneux River, and the gravels and sands are either the remnants of a former estuarine deposit or of a beach formed when the land was some 20 ft. or more lower than at present.

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