Page:Encyclopædia Britannica, Ninth Edition, v. 11.djvu/60

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cases of secondary origin, and have been produced by the alteration of the granite. The mere presence of water is not incompatible with a pyrognostic origin; and Forbes has asserted (op. cit.) that specimens of lava, taken from a current on Etna while the lava was still flowing, contained crystals of stilbite, a mineral containing 16 per cent. of water. Mr Sorby has shown, too, that the quartz of volcanic rocks contains microscopic cavities enclosing liquid. It appears, indeed, that in the fusion of all eruptive rocks water has played a very important part. Dr Haughton has sought to reconcile the opposing views as to the origin of granite by admitting what he calls a hydrometamorphic origin for this rock. He believes that the rock, having been poured into veins and dykes when in a state of fusion, was subsequently altered by the action of water at temperatures which, though high, were insufficient for the fusion of the granite (On the Origin of Granite: an Address to the Geol. Soc. of Dublin, 1862).

Granitic rocks are extensively used for constructive and decorative purposes, though their industrial applications are necessarily restricted by the expense of working so hard a material. Although some granites are apt to decompose on exposure to atmospheric influences, the felspar passing into china-clay, other varieties are remarkable for their extreme durability, as attested by the monuments of ancient Egypt, on which the incised hieroglyphics still retain their sharpness. It appears that in England granite was not brought into extensive use much before the beginning of the present century (Creasy). It is now largely employed for massive structures, such as bridges and sea-walls, as also for kerbs and paving-sets. The best known granites are the grey variety from Aberdeen and the red granite of Peterhead, 30 miles north of Aberdeen. The granite of Dartmoor in Devonshire, and of the huge bosses which protrude through the clay slate of Cornwall, are largely worked as building and ornamental stones (for description of these granites see Sir H. T. de la Beche's Report on the Geol. of Cornwall and Devon). In Ireland there is much fine granite, which is quarried to a limited extent, the Castlewellan granite having been used in the Albert Memorial in Hyde Park (Hull's Building and Ornam. Stones, 1872). The hornblendic varieties of granite are remarkably tough, and are largely employed for road-metal. For this purpose great quantities are quarried in the Channel Islands. Red granite occurs in abundance on the coasts of Maine, U.S., as well as in New Brunswick, and grey granite at Quincy and elsewhere in Massachusetts. Granite is frequently polished when used for monumental and decorative purposes. The polishing is effected by an iron tool, worked first with sand and water, then with emery, and lastly with putty-powder or oxide of tin; when the emery and putty are used, a surface of flannel is interposed between the granite and the iron tool ("On Granite Working," by Geo. W. Muir, Journ. Soc. Arts, xiv., 1866, p. 470).

As an element of scenery granite generally forms rounded hills, scantily clad with vegetation; but it sometimes rises into sharp pinnacles, as in the aiguilles of the Alps. By denudation the rock may break up into cuboidal blocks, which often remain piled upon each other, forming the characteristic "tors" of Cornwall and Devon. Hills of granite are frequently surmounted by masses of weathered rock of spheroidal form, such as the Cornish rocking-stones or logan stones. The weathering of granite often produces boulder-shaped masses in such numbers as to form, around the summit of the hill, a "sea of rocks" (Felsenmeer).

In addition to the references given in the body of this article, the following authorities may be cited:—Lehrbuch der Petrographie, by F. Zirkel, 2 vols., Bonn, 1866; Elemente der Petrographie, by Von Lasaulx, Bonn, 1875; Cotta's Lithology, translated by P. H. Lawrence, 2d ed., London, 1878; The Study of Rocks, by F. Rutley, London, 1879; and the numerous contributions by the Rev. Prof. Hanghton in Proc. Irish Acad., and Quart. Journ. Geol. Soc. Lond. For chemical composition of Cleopatra's Needle, by G. W. Wigner, see the Analyst, 1878, p. 382.}} (f. w. r.*)


GRANMICHELE, or Grammichele, a market-town of Sicily, in the province of Catania, about 8 miles from Caltagirone on the road to Catania. It lies on the side of a hill, the summit of which is crowned by a castle which, along with the town itself, was formerly a fief of the Brancatelli Butera family. Beautiful marble is found in the vicinity, and the inhabitants, who in 1871 numbered 10,058, trade in oil.


GRANSON, Grandson, or Grandsee, a small town in Switzerland, canton of Vaud, is situated near the south-western extremity of the Lake of Neufchâtel. It possesses the ruins of an old castle, containing a collection of antiquities, and has a very ancient church, once connected with a Benedictine abbey, with a number of pre-Christian images. The town is of Roman origin. It was captured in 1475 by the Eidgenossen, and retaken in the following year by Charles the Bold; but in March of that year the Eidgenossen again defeated him near Granson with great slaughter. From that time till 1803 it was one of their lordships. The site of the battle is marked by three great blocks of marble. The population of the town in 1870 was 1587.


GRANT, Mrs Anne (1755-1838), a Scottish authoress, generally known as Mrs Grant of Laggan, was born at Glasgow, 21st February 1755. Her father, Duncan MacVicar, who held a commission in the army, went in 1757 with his regiment to America, and his family followed him in 1758. He received an allotment of land on retiring from the army in 1765, but ill health compelled him to return to Scotland in 1768, and after the outbreak of the revolutionary war his lands were confiscated. In 1779 Anne married the Rev. Mr Grant of Laggan, near Fort Augustus, Inverness, and on his death in 1801 she was left with a large family and only a very small income. It being known to several of her friends that she occasionally wrote verses, a proposal was made that she should publish a volume of poems, and this being acceded to, the names of as many as 3000 subscribers were obtained. The volume appeared in 1803 under the title of Original Poems, with some Translations from the Gaelic, and met with a rather favourable reception, on account of its easy versification and the truth and tenderness of the sentiment of some of its smaller pieces. In 1806 she published Letters from the Mountains, being a Selection from the Author's Correspondence with her Intimate Friends from 1773 to 1804, which, by its spirited descriptions of Highland scenery, character, and legends, awakened a large amount of interest. Her other works are Memoirs of an American Lady, with Sketches of Manners and Scenery in America as they existed previous to the Revolution (1808), containing reminiscences of her stay with Mrs Schuyler, the lady with whom she spent four years of her childhood in America; Essays on the Superstitions of the Highlanders of Scotland (1811); and Eighteen Hundred and Thirteen, a Poem (1814). After the death of her husband, Mrs Grant resided for some time on a small farm near Laggan; but in 1803 she removed to Woodend near Stirling, in 1806 to Stirling, and in 1810 to Edinburgh, in the society of which she was until her death a prominent figure, being much esteemed for her conversational powers, her tact and good sense, her cheerfulness of disposition, and her thorough kindness of heart. For the last twelve years of her life she received a pension from Government; and this, along with her other sources of income, not only placed her in easy circumstances, but enabled her to gratify her generosity by giving to others. She died November 7, 1838.

See Memoir and Correspondence of Mrs Grant of Laggan, edited by her son J. P. Grant, 3 vols., 1844.