386 Transactions. — Geology. 



from the smallest vessel might pass into the one next in size, 

 and so on. Water was then allowed to run slowly upon the 

 pasty mixture, which was stirred continuously, so as to drive off 

 the vegetable matter and lighter products. The process was 

 continued until nothing remained of the original soil except the 

 heavier and insoluble sands and grits. After allowing the mud 

 and lighter sands which had overflowed into the different vessels 

 to settle, the water was drawn off, and the sediment or deposit 

 contained in each was carefully collected and placed in an oven 

 to dry. The same plan was followed with a number of other 

 specimens from the hills where the lands had not been broken 

 up, as also from other places outside Napier, and in each 

 instance the results were very similar. The products, as far as 

 I have been able to make out with any degree of certainty, are : 

 pumice sands, magnetic iron sands (magnetite), lava, ashes, 

 felspar, nepheline, leucite, and olivine. Under the microscope 

 beautiful specimens of minute glass-like rod crystals of leucite 

 were common, having a faint black or dotted line running 

 through them similar to those described by Rutley. 



It is a curious fact that the whole of the East Coast between 

 Poverty Bay and Cape Kidnappers has a black soil similar to 

 that covering the Napier hills, the only difference being in the 

 thickness of the deposit, which varies from 4 inches to about 

 16 inches. 



Since writing the foregoing, I have found at Petane a peculiar 

 black sand or soil deposit, about 8 inches in thickness, inter- 

 bedded with fine sands like those which form the highest beds at 

 Battery Point, Napier. This black sand has a close resemblance 

 to the black soil covering the surrounding hills, and but for the 

 somewhat greater compactness of the former, due, no doubt, to 

 pressure, it would be difficult to distinguish it fi'om the present 

 surface soils. I have washed specimens of this black sand, and 

 I find that it also is of volcanic origin. Scoria, lava, obsidian, 

 olivine, perlite, felspar, mica, and a trace of magnetite are dis- 

 tinguishable ; but some of the sands I am still unable to identify. 

 Alter washing, the sand is not unlike emery powder in appear- 

 ance. 



From the results of my experiments I feel convinced that the 

 East Coast Distiict of this island has been subject, at a not very 

 remote date, to dust showers of volcanic ejectamenta. Had the 

 wind been blowing fiom the north-west at the time of the recent 

 eruptions, it is a matter of certainty that the dust showers 

 which fell in the district extending m a north-easterly direction 

 for about 120 miles from the seat of the volcanic outburst, 

 would have fallen throughout the East Coast District as far as 

 Napier and the Hawke's Bay river system. Within 76 miles of 

 Napier there are many volcanic cones, iucludiug the semi- 

 dormant Tongariro and the not - altogether - extinct cone of 



