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may not be superfluous if, before entering into the main object of this report, I describe briefly the geological and mineralogical characteristics of lignite or brown coal.

Every coal of tertiary age is called a lignite, because in many instances its woody structure can still be clearly discerned; it is called brown coal, not only from its brown streak, but also because some kinds, when decomposing, become dark brown, and are then used as pigments—(umbra). Lignite, besides being light and bulky, has much less carbon than true coal, so that 60 per cent. of carbon may be considered a fair average; but it has a larger amount of oxygen, and is, besides, often impregnated with sulphuret of iron and mixed with argillaceous matter; even the best qualities are, therefore, seldom used for steam purposes, and in most instances the empyreumatic smell and the great amount of iron pyrites which it contains, are sufficient reasons to prevent its being used for domestic purposes.

There are, it is true, some lignites which graduate insensibly into coal, but they are very rare, and when they occur we can trace the change of their characteristic structure to local and secondary causes, as for instance, volcanic eruptions in the neighbourhood.

There is another marked difference between true coal and lignite, namely, that whilst the former retains its compactness and crystalline structure when in contact with the atmospheric air, the latter soon cracks and crumbles away.

The specimen in our geological collection, taken two years ago from the best part of the main seam of the tertiary lignitiferous beds in question, has already cracked in different directions, although it has been carefully bound with strings; and will soon be nothing but a heap of crumbling fragments.

I may here add from Dr. Page’s “Handbook of Geological Terms,” his description of lignite:—“Wood coal or fossil wood, more or less mineralised and converted into coal. The lignites are usually of a dull, dark-brown appearance, compact or laminated, and revealing the woody texture; and never present the crystalline structure or pitchy lustre of true coal. They burn with much smoke and dull flame, are poorer in carbon or coke than common coal; give much less heat, and leave, in general, a large residuum of earthy ashes.”

All the lignites of the province of Canterbury are of nearly the same character, being of very medium quality; they may safely be compared to the Motupipi lignite, in Massacre Bay, but are far inferior in quality to those of Drury, Auckland, or to that of Jenkins’ coal mine of Nelson. In the geological part of this report I shall dwell at more length upon this subject, and describe those seams of lignite which have already come within the range of my observation. I shall now proceed to sketch the position of the lignitiferous beds lying on the north-western flank of the Thirteen Mile Bush Range, and afterwards give you a description of their geological structure.

In ascending the Kowai, where it issues from between the Mount Torlesse and Thirteen Mile Bush Ranges, we find it dividing into two main branches, the principal one of which flows in a north and south direction from the centre of Mount Torlesse, whilst the smaller one, known as McFarlane’s stream, after flowing for about three miles in a west to east direction, has a north and south course, its principal sources lying in the western slopes of Big Ben, the name given to the northern part of the Thirteen Mile Bush Range.

A ridge about 3,600 feet high, divides the head waters of the McFarlane stream from those of the Acheron, whilst another range, of an altitude of 4,000 to 4,500 feet, running parallel with the Thirteen Mile Bush Range, forms the western water-shed towards Lake Linden.

As the valley of McFarlane’s stream, above Mr. Thomas’ station is very rocky and precipitous, and covered with dense bush, the track usually taken to reach the open country at the sources of the stream, is over a grassed saddle, 3,074 feet above the sea. This country is remarkably broken, as the loose character of the tertiary strata has offered little resistance to the mountain streamlets descending from the flanks of Big Ben.

This basin, lying at an altitude of 2,700 to 3,200 feet above the level of the sea, is bounded on the eastern side by the western slopes of Big Ben, on the western by the eastern slopes of the Lake ridge; and on the southern by the ridge or saddle which unites the two ranges; and is traversed by the numerous small branches of the McFarlane stream, the principal ones coming from Big Ben.

The Thirteen Mile Bush Range consists of palaeozoic rocks of varied character, clay slates, alternating with sandstones.

The slates are sometimes blue, assuming the character of a true clay slate, and sometimes become coarse and lighter in colour, when they may be called greywacke slates.

The sandstones also undergo many alterations from a dark steel colour and compact semi-crystalline structure to true greywacke or mudstones.

Some abound in minute specks of mica, others take a black colour as if from carbonaceous matter, and some become gritty and even change into pebble beds.

Although many minor changes are observable, the general strike of these unfossiliferous strata is from north-north-east to south-south-west, with a dip from 60 to 80 degrees to the west-north-west.

The same strata occur in the Lake ridge, of which I examined only its northern termination at Porter’s Pass, where the strata have whirled round, striking from the west-north-west to the east-south-east, with a dip of 70 to 85 degrees to the north-north-east.

But I may here state that the strata stand often in a vertical position, and that reversed dips also sometimes occur.

When examining the extent of the Kowai coal measures, I ascended McFarlane’s stream and found several pieces of coal in its bed, which, although very small, I instantly discerned to be lignites.

Although the existence of this tertiary basin so high in the mountains was unknown to me, it was not quite unexpected, as I had previously received fossils and lignite from another tertiary basin of large extent in the upper Waimakariri country.

There is not the least doubt, that during some epochs in the tertiary period, the greater part of New Zealand was submerged beneath the sea, and also that two sub-divisions, at least, are represented by different formations, enclosing deposits of lignite.