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deep blue waters through which the eye can no more penetrate. Up the Fiords of the Te Anau and Manipori Lakes there are many places where there is no beach at all, but where the rocks rise perpendicularly out of the water for hundreds of feet; there it may be said that there is a precipice above and a precipice below the lakes. If the waters of the lakes were suddenly to dry up, the present shore line would, I believe, appear in most places to be the edge of a precipice. On the Waikathu Lake, one of Mr Rees’ boatmen tried the depth of the lake near Queenstown by means of a weight attached to the end of a rope; two hundred (200) fathoms of line were let out before reaching what was considered to be the bottom; similarly, on the Wanaka Lake, seventy (71) fathoms were let out. These results, although they cannot be relied on as precise, are of value as showing how very deep the lakes must be. Soundings of the lakes, carefully taken with deep-sea sounding apparatus, would aid in the solution of the problem—“By what means were the lakes produced?”

The recent development of inland navigation has directed attention to the fickle and uncertain winds that prevail on the lakes. The prime cause of this phenomena is accounted for by the principal thermal contrasts that underlies the explanation of all the motions in the atmosphere, viz.,—The tendency of cold air to supply the warmer and more rarified. The secondary causes are the unequal radiating powers of land and water, and more especially in this case in the very unequal and mountainous surface of the country surrounding the lakes; the cold mountain air descends into the gullies, and they all open into the lakes. Then again, they lie in different directions, and so receive the heat of the sun at different times of the day. The consequence of these varied influences at work is a condition of unstable equilibrium in the atmosphere, which, when intensified by a strong N.W. wind (the prevailing wind) raises a sea on the lakes that—confined within their narrow limits, and broken on many headlands and islands—becomes for the time a tumultuous assemblage of waters, against which it is in vain for human effort to contend. The action of the winds on the Te Anau Lake, from its greater size and diversity of shape, is more interesting than on any of the other lakes. Sometimes both a storm and a calm are the same time. Sometimes it will blow down the lake and at the same time be calm up the fiords, or vice versa. When such is the case, there is a sort of heaving motion over the calm part. During warm settled weather the phenomena of “land and sea-breeze” so grateful in warm countries prevails on the lakes. On the Te Anau Lake, where, on account of the large extent of downs on its east side, the radiation is more regular than from the surroundings of some of the other lakes; this effect during the intervals it operates was seen to be so regular, morning and evening, that it almost became a measure of time; and from the tidal effects that the breeze had on the Te Anau, it seemed to dignify it with the attributes of a sea.

Rivers.—The two principal rivers of the country surveyed, are the Waiau and Kawarau, these, together with the Upper Oreti and Wakaia, represent the drainage of the country. The Waiau issues from the Te Anau Lake, and after a very rapid sinuous course of 10 miles it enters the Manipori Lake at a distance of 5½ miles in a direct line from its exit from the Te Anau; after mingling its waters with those of the Manipori Lake, the Waiau leaves it at a distance of 6 miles south from where it entered it; for the first 5 miles of its course, after leaving the Manipori Lake, the Waiau flows E. by S. in a slow sluggish manner; at that distance it receives the Mararoa, a very considerable tributary, it then suddenly bends to the south, and at the same time quickens its current; it then pursues a rapid course of upwards of forty (40) miles in a general direction, very nearly due south, when it falls into the sea. The Waiau receives in its course, from the west side, the Borland, Monowai, Dean and Lillburn in the order named; and similarly from the east the Mararoa, Wairaki, Orawea, and many smaller streams; each of the streams just named is of considerable size, and two of them, the Mararoa and Monowai, may be classed as rivers, and will yet be noticed as such further on; still, so far as appearances indicate, there is no very perceptible increase of the Waiau after leaving the lakes; it seems to issue from them full-grown; its average breadth is 150 yards, its depth may be from 10 to 20 feet, and the rate of current, after being joined by the Mararoa, from four (4) to seven (7) miles an hour; judging of the volume of rivers, by the extent of country drained by them, the Waiau would be rated at rather more than one-third of the Clutha. In this case, however, I think, from causes already mentioned, that there will be greater precipitation on the western watershed of the Waiau, than on some of the watersheds of the Clutha, many of the latter being secondary ridges of mountains in the interior; if so, then there will have to be an allowance made in favor of the size of the Waiau.

The Mararoa takes its rise by means of two branches in the Livingstone Mountains, which unite together about half a mile