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At the point O, I found a bed of grit cropping out on a steep part of the hill-side, and by clearing the surface I got a section of the strata about 70 feet thick, shown on Diagram 10, the dip here is S.S.E 4 degrees. Both above and below the regular beds shown, the accumulation of debris is so great as to stop the work of excavation, the face of the trench at a being nine feet deep, yet nothing solid was seen above the bed of black sandstone. Below the first bed of grit at b no solid rock is found, though a great many places where examined to the depth of eight or nine feet, for I was unwilling to abandon a place where the strata, whenever found, were so regular and containing so much shale, which is always found in the immediate neighbourhood of coal. The lower part of this section is 970 feet above the sea.

At P, 805 feet above the sea (see Diagram 11) loose small coal was found spread over the surface of the ground, on the side of a steep spur, at the place marked d, and on tracing this up, a regular bed of one foot six inches thick was found, composed of small coal mixed with a little broken shale and other rocks, above this was a bed of broken shale, and above this again, surface soil and debris. This bed of coal was resting on a solid stratum of hard white sandstone, quite smooth and polished, with longitudinal scratches, the whole evidently formed by the friction of loose soft matter mixed with harder particles sliding down the surface of the rock. This section like the last shows everything in its true position from actual measurement, for I was anxious where it was possible to show exactly how the strata lie on this hill side. You will observe that in the lower part it is very steep and irregular but gradually becoming more level as it ascends. I traced it by digging a trench down to the top of the hard sandstone, from d to a, at which point, being nine feet from the surface, I started it and commenced a fresh one at the surface at c, keeping on the top of the bed of sandstone to b, when the depth of the trench again obliged me to desist, and as there was no satisfactory bed above, from which to commence again, I left the place, as it was not worth while to drive for a seam one foot six inches thick. However it is satisfactory that at this point the strata have the appearance of being regular. It will be observed that at several places the strata are much in this respect has been caused by the sudden bending. Further under the surface the strata are, I pretty regular, and at Q there is a small seam of shale and coal dipping to the W. at an angle of 10 degrees.

At R, 1258 feet above the level of the sea, there is a seam of coal three feet thick dipping to the N.W. 10 degrees. I cleared the face of the seam and intended to have driven in a few yards, but the outside was so very soft and wet that it could not be done without close timbering, which was not worth doing at that time, as the position is not favourable for working, even if a three feet seam can be considered workable in the first place, in a district where so many larger ones exist. It is unnecessary to mention all the places where trials were made, for in most of them nothing was found but debris.

On the whole this exploration on the mountain side, though it has not exposed the outcrop of workable seams, has been very useful in showing the position of the strata at various points, and different elevations, and from what I have seen I have come to the following conclusion, viz :—

That on the side of the table land of Mount Rochfort, between the Wariatea and the Waimangaroha Rivers, it is useless to seek for coal seams or indeed solid rock at all, (except in a very broken and distorted shape), at a less elevation than from 600 to 800 feet above the sea. Above this the strata are much more regular, and continue to get more level and less broken up to the edge of the table land. Perhaps much regularity of surface need not be ex-

pected under 1000 feet; but I think this distortion may only continue a short distance from the surface, on the steep hill side, where the beds appear to have been folded over and broken off while the whole mass was being elevated and that regular strata will be found at a much lower elevation in the body of the hill. For it is evident that while the whole was being forced up the surface would bend and slide while the interior of the mountain might remain almost unchanged except in elevation.

From the edge of the table land and over it to the base of Mount William, the nature of the surface and probable condition of the strata have been treated on in my report of September 3, 1862.

The lines from station 15 to 27 were cut down a spur to the plain, to connect the upper with the lower part of the survey.

After completing this part I traversed over the table land from station 18 T to the gorge at the junction of the north and south branch of Waimangaroha, and connected this part with Coal Brook Dale on Plan 4.

The gorge of Waimangaroha is a most extraordinary chasm, having apparently been torn open by some great convulsion; the sections from A. to B. will give some idea of its nature, it is from survey and rough measurements, and the horizontal and vertical scales are the same.

The walls of the Gorge on all sides drop from the level of the table land in perpendicular and in many places overhanging cliffs from 300 to 400 feet high; from the base of which to the edge of the river on each side, there is a steep shelving base bank formed of the broken rocks alone; in one place this bank is almost covered with hundreds of tons of coal fallen from the large seams on the face of the precipice, at a, there is a splendid section exposed, about 350 feet deep, shown on the margin of Plan 4; in this there are several seams of coal but it is impossible to examine them closely on the face of the precipice, as I could only get to the lowest which is five ft. six in. thick; the remainder of the section was constructed as before described; but at the distance of nearly half a mile it is almost impossible to distinguish the different rocks, particularly coal and shale which have long been exposed to the sun and atmosphere. The section, such as it is, is given below.

A little further to the south on the same precipice the whole of the beds of coal and shale join, (the intermediate bed of 42 feet of grit having run out,) and form after their junction a very large bed of coal and shale; this cannot be traced further, as there is a slip which covers everything up, but beyond this again there is a large seam exposed on both sides of the river at C, Ca, Cb, Cc, Cd. I measured this seam and the strata above it carefully on the spot, and got the following section which is drawn to scale on the margin of Plan 4.