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The distribution of these sands, according to the size of their particles, is 

 very instructive, the deposits being of two kinds — beach formed and river 

 formed. The former are principally on the West Coast, both gold and iron 

 sand being of very fine grain. The greatest altitude at which any beach gold 

 has been found is about 125 feet above the sea, at Watchman's terrace, north 

 of the Grey river. It is found everywhere from Cape Farewell to Jackson's 

 Bay, the richest deposit being at Okarita, about the centre of the great West- 

 land Bight. The coast line south of this does not favour the deposit of fine 

 gold, having bold rocky shores and headlands. On the sandy beaches of the 

 south and east coasts of Otago auriferous sand again appears, and has been 

 found as far north on the East Coast as the commencement of the shingle 

 formation of the Canterbury Plains. 



In the North Island the great iron sand deposits have their maximum at 

 Taranaki, but extend north and south of that place, rarely being found at a 

 greater altitude than ninety to one hundred feet above the present sea level, 

 though small quantities can be found in nearly every sti'eam, except where 

 flowing wholly within marine tertiary rocks. No gold has as yet been 

 found with any of these deposits in the North Island, The river-formed 

 deposits of gold of the interior of the South Island are divided into three 

 groups, according to their position and the manner they are worked. The 

 oldest drifts are deposits at high levels, out of reach of the present drainage 

 system of the country, so that they can only be worked by bringing water to 

 bear upon them by a system of "fluming." In Otago such terraces have 

 formed the source of the bulk of the alluvial gold obtained from rich 

 diggings of the second class, which are marginal deposits of rivers and streams, 

 or shallow alluvial flats. Gabriel's Gully is one instance of this, as at the 

 Blue Spur, between Gabriel's and Monro's gullies we find a patch of the high 

 level older drift that has been tapped and sluiced down the bed of a modern 

 stream which concentrated the gold. The remaining form of alluvial gold is 

 that liberated by streams which are excavating rocky beds, but the amount is 

 very insignificant compared to that obtained in Victoria with this form of 

 mining. The quantity of gold got by shallow sinking on false bottoms in 

 Otago, has naturally led miners to expect that deep leads will be found to rest 

 on the true rock bottom. This subject requires a rigid enquiry into the causes 

 which have operated in producing the surface features of the country. 



We see, as previously stated, that in the West Coast district, a 

 stratum of auriferous alluvium is found to slope to the south from the Nelson 

 province, until at Boss it forms a true deep lead, being worked by under- 

 ground mines that are below the sea level, and are kept dry only by pumping. 

 Btit the basins in Otago are very different in character, being deep depressions 

 in the rock which have no outlet at the present time, except through rocky 

 gorges. These basins have been, to some extent, moulded in their form by a 

 previous extension of the glaciers, during the great Pleistocene elevation of the 

 New Zealand area ; but the depressions being partly occupied by Brown coal 

 and other Tertiary strata, proves that they are of much higher antiquity than 

 that period, and that the original inequalities are due to dislocations. But, at 

 the same time, there is no question that the glaciers have been the most active 

 agents in breaking up the surface rocks, and filling the depressions with the 

 auriferous alluvium. This is especially evident in the western district, where 

 the glaciers are still at work, and where the valleys which they occupied during 

 their previous greater extension have not been filled up, but are now occupied 

 by lakes. We have, in these cases, an opportunity of examining the configu- 

 ration of the valleys by means of the sounding line, and Plate 19, which is a 

 map and a diagramatic section of the N.W. district of Otago, between the 

 Wakatipu lake and the West Coast, will assist in making clear the nature of 



