Page:Encyclopædia Britannica, Ninth Edition, v. 17.djvu/510

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468 NEW ZEALAND Average Temperature of Seasons. 1 Stations. Spring. Summer. Autumn. Winter. 1881. 1882. 58-0 56-9 54-4 53-8 51-2 SO-6 1881. 1882. 65-2 65-4 61 6 61-5 57-3 56-8 1881. 1882. 61-9 61-9 58-3 57-8 54-1 52-3 1881. 1882. 53-4 52-8 49-4 48-8 45-4 43-8 Wellington On the whole, the New Zealand climate is admirably suited to Europeans. In the Colonial Office List for 1883 it is stated that, according to the official reports of the medical department, whereas the annual mortality from all diseases out of every 1000 British soldiers quartered in the United Kingdom was 16, it was only 5 out of every 1000 in the troops quartered for more than twenty-five years in New Zealand. The true test of the comparative healthiness of countries is the rate of mortality distributed according to the ages of population ; and different actuarial investi gations show that this rate is light for New Zealand. It is generally supposed that in the course of ages volcanic action has gradually, by an alternate process of subsidence and upheaval, left New Zealand as it is. There are lines of volcanic craters stretching across the North Island, one at the Bay of Islands, another at Auckland, and a third from Mount Egmont near New Plymouth to White Island, an active volcano in the Bay of Plenty. There are evidences in the South Island of submarine volcanic action. Slight shocks of earthquake are often felt in different parts of New Zealand, but none of great severity has been felt since 1855. During 1882 twenty-eight shocks were recorded, only one being at all severe, while ten were described as "smart," and the other seventeen were slight tremors. A description of the general geological structure of the islands, so far as it is at present ascertained, is contained in the sketch geological map of 1883 by Dr Hector, the director of the geological survey of New Zealand, who has kindly allowed an advance proof to be available for this article (see Plate XIV.). The classification adopted in this map is founded on a mass of palaeontological data, but, owing to the unavoidable absence hitherto of minute surveys, is merely provisional. The following is an abstract of some of Dr Hector s remarks on this map : The post-Tertiary (Recent) deposits have accumulated with great rapidity in New Zealand, owing to the mountainous character of the country giving to the rivers, even when of large size, the char acter of torrents which are liable to occasional Hoods of extreme violence. The Pliocene formation belongs to a period when New Zealand was the mountain range of a greatly extended land area. The Upper Miocene beds are limited in their extent to the southern and eastern districts of the North Island, and in the South Island occur as patches. The New Zealand seas have yielded about 450 species of existing shells, of which 120 have been found in this formation, together with 25 forms which are now extinct. The Lower Miocene represents a period of great depression, and the deposits are remarkable for the absence of evidence of volcanic activity in any part of the region, and for the abundance of marine life. The Upper Eocene is a very marked formation of calcareous sandstone composed of shell fragments with corals and Bryozoa, and is a shallow-water and littoral deposit. Intense volcanic activity prevailed during this period in both islands. In the upper part of the Cretaceo-Tertiary formation occurs the valuable building stone, known commercially as the "Oamaru stone," a calcareous sandstone which is very easily worked, but which hardens when exposed to the weather. The principal coal deposits of New Zealand occur in the Cretaceo-Tertiary formation, but always at the base of the marine beds of the forma tion, in every locality where they occur. The Lower Greensand, which is confined to a few localities of limited extent, is very rich in fossils of the genera Belemnites and Trigonia, with a few saurian bones and large chimaeroid fishes. It has been found necessary to include in the Trias a thickness of strata which is quite unusual in other parts of the world, but the close connexion which exists throughout, founded both on palaeontological and on stratigraphieal grounds, and the clearly denned Permian character of the next underlying formation, renders this classification absolutely necessary. Saurian remains are associated with the Permian beds at Mount Potts, which were referred by Dr Hector to Ichthyosaurus in 1871, but subsequently to the genus Eosaurus of Marsh. The further remains obtained of this saurian are, however, of such gigantic size as compared with the original types found in Nova Scotia, in which the vertebrae were 2| inches in diameter, that the determination may be doubted. The Lower Carboniferous and Upper Devonian forma tion is of considerable importance from the large share it takes in the structure of the great mountain ranges, and from the occa sionally great development in it of contemporaneous igneous rocks with which are associated metalliferous deposits. The igneous rocks 1 Spring begins with September, summer with December, &c. (basic volcanic and acidic volcanic) have played an important part in almost every formation in New Zealand, marking great movements of the earth s crust at the different geological periods, while the superficial and later-formed volcanic rocks occupy nearly one-third of the area of the North Island. The geysers and boil ing springs in the North Island give rise to the formation of siliceous sinter deposits, which must be included as the most purely acidic products of volcanic action, and are due to the decomposition of the older rocks by the action upon them of fresh water ; but in the case of White Island and other localities where the decomposi tion is brought about by the agency of sea water, the sinter deposits are formed chiefly of sulphate of lime and not silica. The census of 1881 shows that out of a total population (other than aboriginal) of 489,933 there were 14,273 miners, of whom 12,996 were returned as being engaged in gold mining, and 1087 in coal mining. The principal quartz mines for gold are in the Thames and Coromandel districts near Auckland in the North Island, but several auriferous reefs are extensively worked in the Otago,_ Westland, and Nelson gold-fields in the South Island. There is good reason to believe that quartz mining in New Zealand is still in its infancy, and that its indefinite extension can be ensured by the judicious application of more capital. Alluvial gold mining chiefly exists in the Otago, Westland, and Nelson districts. Gold drift, as it is called, is found in river-beds and on the sea-coast, where it can be worked with comparative ease, and also in thick deposits of gravel, the working of which requires mechanical water-power, and often large expenditure. The opinion entertained in many quarters that the auriferous resources of New Zealand will soon be exhausted, and that the gold mining industry is approaching a rapid decline, is certainly not based upon fact. There still, it is reliably stated, exist large areas, both in the North and South Islands, that on geological grounds are highly promising for the existence of original or primary auriferous deposits, namely, quartz lodes. With regard to secondary or derived auriferous deposits namely, gold drift the more easily and cheaply accessible of them have, no doubt, been worked out, more or less, but the South Island still contains tracts that offer profitable employment to the miner for generations to come. The total quantity of gold produced in and exported from New Zealand from 1st April 1857 to 31st March 1883 was 10,144,926 ounces, valued at 39,747,940. The quantity during the year ended 31st March 1883 was 248,862 ounces, valued at 994,555. Good coal is obtained in many parts of New Zealand. The number of coal mines in work in 1882 was 104 ; and the output during 1882 was 378,172 tons, being 215,954 tons more than the output in 1878. Silver is chiefly extracted from the gold produced in the Thames district, but other mines containing silver ores have been found. There are many other valuable ores copper, iron, lead, zinc, antimony, chrome, and manganese some of which are being worked. Several fine mineral oils also are obtained. Building stones of various kinds and of excellent quality abound. Marble and cement stones occur in many places. In 1881 there were 127 brick, tile, and pottery manufactories in work ; and their lands, buildings, and machinery were valued at 105,765. There are extensive deposits of iron-sand on the west coast of the North Island. The following official table, in Dr Hector s Nciv Zealand Hand book, classifies the land according to the geological subsoil : North Island. South Island. Totals. 1. Fluviatile drifts, one-third agricultural... 2. Marine-Tertiary ,tvo-thirds agricultural ) (the rest pastoral) f Sq. miles. 8,447 13,898 Sq. miles. 6,286 4,201 Sq. miles. 14,733 18,099 3. Upper Secondary, coal-bearing, pastoral.. 4. Palaeozoic, pastoral 2,390 5,437 2,110 20 231 4,500 25,668 15 308 15 308 fi. Granite, worthless 5 978 5 978 .7. Volcanic, one-sixth agricultural (the ) rest pastoral) ) 14,564 1,150 15,714 Square miles 44 736 55 264 100 000 A study of this table, he adds, shows that " in the whole colony there are about 12,000,000 acres of land fitted for agriculture, and about 50,000,000 which are better adapted for pasturage; but from these estimates allowance must be made for about 20,000,000 of surface at present covered by forest." Dr Hector also reports the prevalence, in the north of Auckland and in the lower part of the Waikato Valley, of light volcanic soil, interspersed with areas of clay marl, which in the natural state is cold and uninviting to the agriculturist, but which under proper drainage and cultivation can be brought to high productiveness. He adds valuable information, in substance as follows, respecting other districts. In Taranaki and Wanganni districts the soil is very rich, and on the surface is formed by the decomposition of calcareous marls intermixed with the debris from the lava streams and tufaceous rocks of the extinct volcanic mountains. The forest growth which generally covers the land proves its productiveness,