Its extreme richness in number of species (it comprises six-sevenths of the European flora) and the extremely restricted areas of many of them point to a great antiquity.
Over six-sevenths of the shipping is British.
Although of no great thickness it covers six-sevenths of the island, rising in a series of steps or platforms to a height of nearly 1 10o ft.
More than thirty mineral substances are obtained in commercial quantities from the mines, quarries and wells of New York, but of the total value of the mineral products in 1908 ($45,6 6 9, 861), nearly six-sevenths was' represented by clay products ($8,929,224), pig iron ($15,879,000), stone ($6,157,279), cement ($ 2, 2 54,759), salt ($2,136,738), petroleum ($2,071,533), and sand and gravel ($1,349,163).
The development of dairyfarming has led to the spread of settlement, especially in the west of North Island, where large tracts of fertile soil formerly covered with forest have now been cleared and converted into dairy-farms. Of 1,850,000 cattle in the colony, two-sevenths are dairy cows.