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Lawrence in Canada. BRITISH. Wanting? FOREIGN. Beds of gneiss and quartzite, with interstratified limestones, in one of which, 1000 feet thick, occurs a foraminifer, Eozoon Canadense, the oldest known fossil. Order of Succession of Sedimentary Formations. Frequent Unconformability of Strata. Imperfection of the Record. Defectiveness of the Monuments greater in Proportion to their Antiquity.
Many of these limestones are of such composition as to be acted on freely by the elements of the atmosphere, which, in the form of nitric acid, combine with the earthy and alkaline bases of calcareous rock, and give rise to the formation of nitrates with the liberation of carbonic acid; hence the disintegrated rubbish of the caves yields nitrate of potash after being treated with the ley of ashes and subsequent evaporation of the saline lixivium.
For here we have an immense area east of the main divide, extending from the middle of Montana up to the Yellowhead Pass in Alberta, or over 350 miles long, where the tops of the mountains consist of jointed limestones or argillites of Algonkian or pre-Cambrian "age," resting on soft Cretaceous shales.
This red under-lyer is, in fact, a great deposit of red sandstone, breccia, and conglomerate with associated porphyry, basalt, and amygdaloid. According to Sir R. Murchison, the Permian rocks are composed, in Russia, of white limestone, with gypsum and white salt; and of red and green grits, occasionally with copper ore; also magnesian limestones, marl-stones, and conglomerates.
Air-breathers of the American Coal. Changes of Condition of Land and Sea indicated by the Carboniferous Strata of Nova Scotia. The next group which we meet with in the descending order is the Carboniferous, commonly called "The Coal," because it contains many beds of that mineral, in a more or less pure state, interstratified with sandstones, shales, and limestones.
Wood plays no part worth mentioning in the fully developed sculpture of Greece, except as it entered into the making of gold and ivory statues or of the cheaper substitutes for these. Stone and marble. Various uncrystallized limestones were frequently used in the archaic period and here and there even in the fifth century.
This may have been the case without regard to the origination of new species, but more probably it was otherwise; or why, for instance, should the polypiferous zoophyta be found almost exclusively in the limestones?
And it is an interesting fact that there is a distinct relation between deposits of magnetic iron ore and the metamorphoses of limestones into marbles; so that this substance not only gives to the marbles their colouring, but also their texture. Even the whitest saccharoidal or statuary marble, which it has not coloured, it has created by the crystallisation of the limestone associated with it.
For carbonate of lime is a widely-spread substance, and is met with under very various conditions. All sorts of limestones are composed of more or less pure carbonate of lime. The crust which is often deposited by waters which have drained through limestone rocks, in the form of what are called stalagmites and stalactites, is carbonate of lime.
We are just as if we were people of Hamburg going to Lubeck by way of Hanover!" I had better have kept my observations to myself. But my geological instinct was stronger than my prudence, and uncle Liedenbrock heard my exclamation. "What's that you are saying?" he asked. "See," I said, pointing to the varied series of sandstones and limestones, and the first indication of slate. "Well?"
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