Manawatu Herald. TUESDAY, NOV. 4, 1902. Geology.

Manawatu Herald, 4 November 1902, Page 2

Manawatu Herald. TUESDAY, NOV. 4, 1902. Geology.

The other day we mentioned that Dr Williams, in his preface to the third volume of the “ Encyclopedia Britannica ” had written “the net effect of scientific research in tho Victorian era was to oause it to be as usually accepted that the age of the world must be reckoned in millions of years.” Theoretical Geology is a science of comparatively recent growth, the geologist bases his deductions on numerous and well observed facts; collects, arranges, and compares, with honest and scrupulous care ; and by such means proceeds from phenomena that are obvious and taking place around him, to the explanation of those that are remote and less apparent. Had tho exterior crust of the earth been subject to no modifying causes, the world would have presented the same appearance now as at the time of its creation, but there has been one continuous change, caused by those operating through the medium of the atmosphere (Atmospheric); the Aqueous, or operations of water; the Organic depending on vegetable and animal growth ; the Chemical, resulting from the chemical action of substances on each other; and the Igneous, caused by heat in the interior of the globe. Thus in order to arrive at a knowledge of tho past conditions of the earth, it is necessary to examine not only the mineral character of the different strata, but to ascertain the nature of their fossils, their order of superposition, and other relations. At the present day, the layers of mud, clay, sand, and gravel depositing in tropical estuaries and seas, will contain less or more the remains of plants and animals peculiar to the tropics ; the deposits forming in temperate regions will contain in like manner, the remains of plants and animals belonging to temperate climates; and should a time arrive when these layers are converted into solid strata, the fossilised plants and animals will become a certain index to the conditions of the regions and areas in which, they were deposited. The classification of rocks are known as Recent, containing the remains of existing plants and animals only partially fossilised; Tertiary, containing plants and animals not differing widely in character from those now existing; Secondary, containing fossil plants and animals of species altogether different from those now existing; Transition, containing few or no fossil plants, and the remains of no higher animals than Crustacea, shell fish, and zopphytes ; and Primary, very bard and compact and totally destitute of organic remains. The Geologist, at the outset of his inquiry, says a well-known writer, is met by the fact that everything beneath and around him is in ceaseless re-action, and change. The causes of this change ha finds in the atoaespiiera that eimlopes the earth,

in the waters that courses its surface, iu the life that peoples it, ia the chemical constitution of the substances of which it is composed, and in the fires that glow within its interior. These are ever and everywhere active ; here wasting and degrading, there accumulating and reconstructing; here submerging ihe habitable dry laud bun .ath the ocean, there upheaving the sea-bottom to form new islands and continents; and anon preserving in the reformed material the remains of plants and animals as evidences of the world’s conditions at the time of their entombment. In this rocky crust we find sandstones that must have formerly spread out as sandy shores; conglomerates that formed pebbly beaches ; shales that were the muddy clays of former lakes and estuaries; limestones that once were living coralreefs ; and coal-beds composed of the remains of a bygone vegetation. Here, also, we discover imbedded corals and shells and fishes that must have lived in the ocean ; reptiles that thronged shallow bays and estuaries; huge mammalia that browsed on river plains ; and plants, some that flourished in the swampy jungle, and others that reared their trunks in the tropical forest. Of all this there is ihe clearest and most abundant evidence ; and by comparing and arranging, by tracing hack from the accumulations of yesterday to the deepest strata in the reeky crust, geologists have been enabled to present a pretty vivid outline of the world’s history, of all its phases and conditions from the earliest time wo have traces of organisation and life, up to the existing order of things, of which Man is the appointed head and ornament.”