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exposed till the water resumed somewhat its original level, when the present formation presented itself. But although this might account for so heavy an accumulation of drift, we must look for the cause of their peculiarity of form in the existing lakes and rivers. I have attentively watched the wide parts of the Kawarau and the borders of the lake to endeavour to obtain some clue to the cause of their formation, and find that around those parts of the banks against which the strongest currents bear, the slopes are rocky and steep, but at the opposite sides (which are affected by a strong back under-current) drift deposits are being formed, both in shape and matter similar to the terraces before described. The slate being of so light a nature, is held longer in suspension by the turbid stream than would be the case with the heavier drifts of other localities, and being affected by the back flow is deposited in the sides of the streams, not acted on by the downward current of the water; the heavier matter sinks to the bottom, but the lighter being longer buoyed up by the action of the water forms the top of the terrace. The accompanying sketch

will illustrate my meaning: the arrows denote the course in which the water flows.

9. The drift deposits in the various river beds are composed of washed boulders of various colored slate and quartz, with traces of porphyry, greenstone, granite, gneiss, and various conglomerates, with fragments of metallic ores. The finer drift being a micaceous sand, resulting from degradation of the mica slate which forms the bed rock, there is throughout but a small proportion of argillaceous matter; it is therefore easily dispersed by the action of water—a great desideratum in mining operations.

10. Gold is usually found beneath these deposits in connection with the heavier kinds of drifts—black sand and the same mineral in boulders, and large pieces, called by the miner, the “Black Maori,”—being the principal. This (which I believe to be a carbonate of iron) is exceedingly heavy, and had consequently a similar form of deposit to gold itself. So intimately connected is this substance with gold that it is considered a sure indication of the value of a claim. I have accompanied this with a specimen of this mineral, containing a spec of gold, which I picked up at the Arrow River—I have known several similar pieces to be found, but this is the first I have been able to obtain. Auriferous matter is not always found in the deepest parts of the river beds, and not at all times on the bed rock; but more frequently on the false bottoms of heavier kinds of drifts. The impetuous floods that occur at the wet season of the year have the effect of lifting all matter from the river beds, and throwing it to the side where the least action exists.

11. The first workings here consisted of beach-washing, which was carried on simply with a tin dish, pick, and shovel; and some of the richest ground that I ever saw during eleven years of Gold Fields experience has been worked by this simple method. The rivers are, however, now occupying general attention; many systems have been adopted to reclaim the rich treasures from their watery bed—the wing-dam was the most in use. This consisted of bags filled with sand and laid with an elbow to the stream, enclosing a portion of the river, which was then worked by the assistance of Californian pumps. But although a great amount of gold was obtained by this means, it was