Rocks

There be three things which are too wonderful for me, yea, four which I know not: the way of an eagle in the air; the way of a serpent upon a rock …— Holy Bible, Proverbs, 30:18-19.

A rolling stone gathers no moss.
— Proverb, dating back to the 16th century.

I had else been perfect,
Whole as the marble, founded as the rock
— William Shakespeare (1564 – 1616), Macbeth, III, iv, 20

Water may polish the rocks, but it nowhere leaves straight scratches upon their surface; it may furrow them, but these furrows are sinuous, whilst glaciers smooth and level uniformly, the hardest parts equally with the softest, and like a hard file, rub to uniform continuous surfaces the rocks upon which they move.
— Louis Agassiz (1807 – 1873)

… in the field some amount of information concerning igneous rocks can be obtained by rubbing down the chip on a grindstone and using a whetstone, carborundum file, or water of Ayr stone for the final grinding. By these and other methods … there are obtained slices of rocks which, though thick, uneven, scratched, and all that is bad, from the point of view of the professional maker of thin sections, are nevertheless capable of yielding much information. With a pocket lens it is possible to make out from such a ‘thin’ section the nature of the minerals present, the texture and the nature of the rock.
— Frank Rutley (1842 – 1904), Elements of Mineralogy, 22nd edition, 1915, 104.

The series of changes which fossil bodies are destined to undergo, does not cease with their elevation above the level of the sea; it assumes, however, a new direction, and from the moment that they are raised to the surface, is constantly exerted in reducing them again under the dominion of the ocean. The solidity is now destroyed which was once acquired in the bowels of the earth; and as the bottom of the sea is the great laboratory where loose materials are mineralized and formed into stone, the atmosphere is the region where stones are decomposed, and again resolved into earth.
— John Playfair (1748 – 1819), Illustrations of the Huttonian Theory, reprinted in A Treasury of Scientific Prose, 191-2, Little, Brown, 1963.

The ‘crust’ of the earth is a cool, relatively rigid shell which is probably not much more than 30 miles [50 kilometres] deep, i.e., less than eight thousandths of the distance from the surface to the earth’s centre. Beneath this shell, heat and pressure rise to such levels that all rock materials are thought to be plastic.
— Walter H. Bucher, ‘The Crust of the Earth’, Scientific American Reader (1953), 55.

More recently, advances in physics have given us methods to put absolute dates, in millions of years, on rocks and the fossils that they contain. These methods depend on the fact that particular radioactive elements decay at precisely known rates. It is as though precision-made miniature stopwatches had been conveniently buried in the rocks. Each stopwatch was started at the moment that it was laid down. All that the palaeontologist has to do is dig it up and read off the time on the dial.
— Richard Dawkins, The Blind Watchmaker, Penguin, 1986.

You force the birds to wing too high,
Where your unnatural vapours creep:
Surely living rocks shall die
When birds no rightful distance keep.
— Gordon Bottomley (b. 1874), To Iron-Founders and Others.

A freestone is a uniform thick-bedded sandstone with few divisional planes. It can be cut or worked easily in any direction, and consequently forms a good building stone. The term freestone is also applied to some limestones of similar character.
— G. W. Tyrrell, The Principles of Petrology, Methuen, 1929, 210.

In the agricultural sense soils are the superficial layers, usually less than a foot in thickness, of disintegrated and decomposed rock material, which is mingled with organic matter, and furnishes the necessary conditions and materials for plant growth.
— G. W. Tyrrell, The Principles of Petrology, Methuen, 1929, 184.

The United States alone, it is estimated by Federal geologists, is robbed of 783 million tons of its native soil every year in this way.
— A. W. Haslett, Unsolved Problems of Science, London 1937.

Rather more than a century ago Sir Charles Lyell, then an Oxford student, noticed that a small lake on his father’s Scotch estate was capable of depositing an appreciable layer of limestone on its bottom within quite a few years — and on his discovery that rocks could be built up as well as worn away is based a large part of modern geology.
— A. W. Haslett, Unsolved Problems of Science, London 1937.

The simplest form of weathering of exposed stone is that due to the physical action of wind and rain in actually eroding material from exposed surfaces. There is abundant evidence to show that this is actually an extremely slow process. Exposed parapet copings of Portland Stone high up on the outside of St Paul’s Cathedral in London have been studied and found to have eroded only 13 mm in 250 years.
— Robert F. Leggett, Cities and Geology, McGraw-Hill, 1973, 334.

It cannot therefore be doubted that the extensive volcanic elevations constituting the high table-land of Armenia and the island Iceland have flowed from sources which were chemically identical. The idea that perhaps all the volcanic formations on the earth’s surface have originated from the same source, or even, indeed, that it is from this very source that all the ferruginous and non-ferruginous rocks have originated by fusion together, is rendered the less improbable by the fact that the mineralogical differences between those Caucasian and Icelandic rocks which present the same mean composition, are not less marked than those observed among other ferruginous rocks of plutonic origin. It would therefore be very interesting to trace the genetic relations existing among the more ancient formations, in a manner similar to that which I have adopted with regard to the volcanic rocks. It would be necessary to select for this purpose only the more extensive and largely developed rock systems, in order to avoid those disturbing influences which may have resulted from the contact of chemically metamorphosed exogenous rocks with those of plutonic origin. These disturbing influences manifest themselves even where volcanic rocks have penetrated in isolated elevations, through calcareous or siliceous sedimentary beds.
— Robert Wilhelm Bunsen (1811 – 1899), ‘On the processes which have taken place during the formation of the Volcanic Rocks of Iceland’, Poggendorff’s Annalen, 1851, No. 6, translated in the Scientific Memoirs, edited by Tyndall & Francis, 1853.

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