336 Transactions. — Geology. 



geological position is in the Cretacco-tertiary series of the 

 New Zealand Geological Survey. The surface of the speci- 

 men, which is one of innumerable equally well-marked 

 samples which might have been chosen, is scored in more 

 than one direction by grooves or stria3, which vary much in 

 depth, the maximum being about yV^^- '> ^^^ w'ere it not that 

 some of these are curved they would present no features dis- 

 tinct from true glacial strite. 



The slip occurred on a surface of the coal-measures dipping 

 at 25°, and was caused by the accumulation of surface-water 

 in a deposit of soil and vegetable growth, the cohesion of 

 which had been destroyed by fires. After proceeding for some 

 distance the direction of the moving mass was changed to 

 about 40° from the straight line by an outstanding mass of 

 quartzose grit, and at this point the whole body plunged over 

 a vertical cliff about 20ft. in height, forming a veritable cascade 

 of mud, and stones, and tree-roots. In the lower portion the 

 angle of slope was reduced to 10°, and at this point a cottage 

 was carried away and destroyed, unfortunately not without 

 loss of life, for an infant member of the family was left be- 

 hind in the confusion, and the mother perished in a heroic but 

 unsuccessful effort to save her child. 



The surface bared in the upper portion of the slip is fire- 

 clay, rendered very slippery by the presence of water, while 

 the part which came away consists, below the soil, of about 

 8ft. of fireclay and quartz grit, the hard fragments of the 

 latter causing the striatiou of the remaining rock, which at 

 the time of my visit was covered with numbers of well-defined 

 grooves. 



Abt. XU. — On the Neighbourhood of Te Aoroa, Northern 



Wairoa. 



By John Harding, of Mount Vernon. 



[Read before the Hawkc's Bay Philosophical Institute, 13th Aug., 1888.1 



Te Aoroa is situated on the west bank of the Northern Wtxi- 

 roa, between Aratapu and Dargaville. This, together with a 

 long stretch of country to its north and south, is classed as 

 " drift " on our geological map. This would apply to the high 

 lands, but about one-fourth is rich alluvial flat and swamp, the 

 hills soft sandstone, varying in colour from snow-white to 

 black. The coast-hills differ much from those farther inland, 

 the latter having a large quantity of bog-iron mixed with the 

 surface-soil, in many parts rendering it impervious to water, 

 and so almost useless for agriculture or grazing. All this hill- 



