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and the carrying on of a payable timber trade, from which the settlers reckoned to obtain occasional employment, is contingent upon the completion of the jetty at Jackson's Bay. The action of the Government is very anxiously looked forward to by the settlers remaining on the settlement, as the fact is very apparent that without the means of shipping our products the outlook is anything but promising. Sufficient evidence, I think, has been adduced to show you the vital importance of this work, and I trust your recommendation to the Government will be of such a nature as will convince them of the urgent necessity and public importance of this work, not merely as a work affecting the immediate vicinity of Jackson's Bay, but as affecting the future development of the whole of the southwest coast, and indirectly the whole of tbe colony. I have, &c, The Commissioners, Jackson's Bay 1 nquiry. D. Macfablane.

Notes on the Geology of the Jackson and Cascade Valleys. The presence in Jackson's Bay and neighbourhood of large masses of igneous and metamorphic rocks pointed to the existence of an igneous belt at no great distance inland ; therefore, whilst engaged on other duties connected with the special settlement, I took the opportunity, during a fortnight's exploration in the Jackson and Cascade Valleys, of noting the more salient points and features in the geology of those districts, thereby enabling me to locate the line of eruption from whence the rocks found along the coast have beeu derived. The results of my observations I now submit for your consideration. My route lay up the Jackson and Arawata Rivers, down to the left-hand branch of the Cascade to its junction with the main stream, thence to within five miles of the point at which the river enters the sea. The main branch of the Cascade I followed up to the point marked A. on the plan, about two miles below where the river comes in from the south-east. Seven miles above the junction of the Jackson with the Arawata I met with tho first indication of the igneous rock in situ. The belt, which is here about a mile wide, consists principally of the dark green serpentine marked X in the series of hand specimens accompanying this paper, with narrow bands of No. 11 running through it, showing a slight dip to the eastward. The whole formation is very much broken up, the jointings of the dark serpentine being filled in with thiu lamina of No. 1 ; this, on continued exposure to the atmosphere, turns into a white pasty substance, and presents a marked feature in the appearance of the country : as, for instance, where great slips have taken place recently, the exposed rock shows a beautiful light-green appearance; but after long exposure tho green changes to white, streaking the ranges with immense white patches that have been taken, when seen from a distance, for quartz and pipe-clay. No. A. (not seen in situ) occurs iv large angular fragments all along tho belt; the top of Mount Richard (from the top of which a complete view can be obtained, on a clear day, of the belt north and south, being composed of an immense cairn of such fragments piled up in indescribable confusion. The same rock is met with all along the Cascade plateau to the sea, more particularly on tho southern break of the terrace bounding the low^er reach of the Cascade Valley. No. Bx., occurring in boulder form, is met with along the same line. The red appearance, which is the characteristic colour of the whole range, is due to the oxidation of the minerals ; the red, white, and green, forming as they do such striking contrasts, presents a very remarkable appearance. The accompanying section, taken near the north end of the belt, together with hand specimens of the rocks as they occur, will better enable you to judge of the nature of the country than any description I can give. The auriferous lode, No. XII., is being prospected. I have failed iv detecting free gold in the stone, and whether the pyrites will be rich enough in gold to pay for its extraction, remains to be seen. The lode, which is of great width and standing nearly vertical, lies about sixty chains to the eastward of the igneous formation, having a north and south strike from this point ou the section line ; the dip of the slates gradually alters, until, at their junction with the eruptive rocks.it shows au angle of 40°. AVhether the same sequence prevails further south lam not in a position to state positively ; but, as seen from Mount Richards, the enclosing rock to the eastward is a dark and defined slate, showing distinct cleavage lines, and standing nearly vertical, forming a bold escarpment and apparently an abrupt transition from the serpentine rocks to the dark slates without the intervening green slates that are found further north. However, this is a matter requiring more careful and extended observation ; enough, if, by directing your attention to this remarkable belt, you may be induced to have it looked into and examined by a competent geologist and mineralogist, the result of whose labours would place you in possession of more extensive aud precise data than I have been able to furnish you with. Above a certain line the belt is entirely devoid of vegetation, and in many places it is bare to the foot of the range. The work of disintegration is going on very rapidly, great slips occurring very frequently, making travelling somewhat dangerous, as in attempting to cross some of those slips a very little disturbance sets hundreds of tons of the debris in motion. From where the formation shows in the Jackson the general course of the belt is south 30° west, widening as it goes south, attaining its greatest width at the back of Big Bay —that is, presuming that the red hill at this point is of the same character as the country I traversed. My furthest south was about twenty-five miles in a straight line from the Jackson to a point where the main branch of the Cascade falls about two hundred feet in about two chains, aud within about two miles of where the river comes in from the south-east. From the Jackson to this point I found the formation cut through by the following streams, forming in many places deep gorges —viz., the Jackson River, left-hand branch of the Cascade, AVood-hen Creek, McKay's Creek, Fall Creek, aud lastly the Cascade River. This stream, after crossing the formation, has followed along the western line of strike for a considerable distance ; but the belt keeps its course irrespective of the present valley formations and other natural features that at present obtain. How much further it may penetrate into Otago further explorations will tell, unless the same formation has been noticed north of Lake AVakatipu. To the westward of the valley I find the slates and sandstone dipping to the west at an angle of 30°. Specimen No. B, slate from Barn Bay Range, south side of Cascade Valley.