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American beetle, Saperda inornata (Cerambycidae), which forms are the result of attacks on buds. Amongst the most remarkthe pseudo-galls of Salix longifolia and Populus angulata, or able galls recently discovered we may mention those found on cottonwood Among the Lepidoptera are gall-forming species Eucalyptus, Casuarina and other trees and plants in Australia. belonging to the Tineidae, Aegeriidae, Tortricidae and Plero- They are remarkable for their variety, and are due to small phoridae. The larva of a New Zealand moth, Morova subfasciato, scale-insects of the peculiar sub-family Brachyscelinae. As Walk. (Cacoëcia gallicolens), of the family Drepanulidae, causes regards the mode of production of galls, the most important the stem of a creeping plant, on the pith of which it apparently distinction is between galls that result from the introduction of subsists, to swell up into a fusiform gall."
an egg, or other matter, into the interior of the plant, and those Mite-galls, or acarocecidia, are abnormal growths of the leaves that are due to an agent acting externally, the gall in the latter of plants, produced by microscopic Acaridea of the genus case frequently growing in such a manner as ultimately to enclose Phyloplus (gall-mites), and consist of little tufts of hairs, or of its producers. The form and nature of the gall are the result thickened portions of the leaves, usually most hypertrophied on of the powers of growth possessed by the plant. It has long been the upper surface, so that the lower is drawn up into the interior, known, and is now generally recognized, that a gall can only be producing a bursiform cavity. Mite-galls occur on the sycamore, produced when the tissue of a plant is interfered with during, or pear, plum, ash, alder, vine, mulberry and many other plants; prior to, the actual development of the tissue. Little more than and formerly, e.g. the gall known as Erineum quercinum, on the this is known. The power that gall-producers possess of inleaves of Quercus Ccrris, were taken for cryptogamic structures. Auencing by direct interference the growth of the cells of the plant The lime-leaf“ nail-galls "of Phyloplus liliae closely resemble the that affords them the means of subsistence is an art that appears " trumpet-galls " formed on American vines by a species of to be widely spread among animals, but is at the same time one Cecidomyia. Certain minute Nematoid worms, as Anguillula of which we have little knowledge. The views of Adler as to the scandens, which infests the ears of wheat, also give rise to galls. alternation of generations of numerous gall-flies have been fully
Besides the larva of the gall-maker, or the householder, galls confirmed, it having been ascertained by direct observation that usually contain inquilincs or lodgers, the larvae of what are the galls and the insects produced from them in one generation termed guest-flies or cuckoo-flies. Thus the galls of Cynips and are entirely different from the next generation; and, it has also its allies are inhabited by members of other cynipideous genera, been rendered certain that frequently one of the alternate as Synergus, Amblynolus and Synophrus; and the pine-cone-like generations is parthenogenetic, no males being produced. It is gall of Salix strobiloides, as Walsh has shown, is made by a large supposed that these remarkable phenomena have gradually species of Cecidomyia, which inhabits the heart of the mass, the been evoked by difference in the nutrition of the alternating numerous smaller cecidomyidous larvae in its outer part being generations. When two different generations are produced in mere inquilines. In many instances the lodgers are not of the one year on the same kind of tree it is clear the properties of the same order of insects as the gall-makers. Some saw-flies, for sap and tissues of the tree must be diverse so that the two generaexample, are inquilinous in the galls of gall-gnats and some tions are adapted to different conditions. In some cases the gall-gnats in the galls of saw-flies. Again, galls may afford alternating generations are produced on different species of trees, harbour to insects which are not essentially gall-feeders, as in the and even on different parts of the two species. case of the Curculio beetle Conotrachelius nenuphar, Hbst., of On galls and their makers and inhabitants see further-J. T, C. which one brood eats the fleshy part of the plum and peach, and Ratzeburg, Die Forst-Insecten, Teil iii. pp. 53 seq. (Berlin, 1844): another lives in the “ black knot” of the plum-tree, regarded T. W. Harris, Insects injurious to Vegetation (Boston, U.S., 2nd ed.
Koch, Die Pfansenläuse A phiden (Nuremberg, 1854); by Walsh as probably a true cecidomyidous gall. The same T. Hartig. Die Familien der Blattwespen und Ilolawespen (Berlin, authority (loc, cil. p. 550) mentions a willow-gall which provides 1860); Walsh, “On the Insects, Coleopterous, Hymenopterous and no less than sixteen insects with food and protection; these are Dipterous, inhabiting the Galls of certain species of Willow," Proc. preyed upon by about eight others, so that alltogether some 1867), pp. 223-288; T. A. Marshall,
Enl. Soc. Philadelphia, iii
. (1863-1864), pp. 543-644. and vi. (1866.
On some British Cynipidae," twenty-four insects, representing eight orders, are dependent for Ent. Month. Mag. iv, pp. 6-8, &c.; H. W. Kidd and Albert Müller, their existence on what to the common observer appears to be "A List of Gall-bearing British Plants," ib. v. pp. 118 and 216, nothing but "an unmeaning mass of leaves." Among the G. L. Mayr, Die mitteleuropäischen Eichengallen in Wort und Bild
(Vienna, 1870-1871), and the translation of that work, with notes, in numerous insects parasitic on the inhabitants of galls are
the Entomologist, vols. vii. seq.; also, by the same author. "Die hymenopterous flies of the family Proclotrypidae, and of the Einmiethler der mitteleuropäischen Eichengallen." Verhandl. d. family Chalcididae, e.g. Callimome regius, the larva of which zoolog.-bot. Ges. in Wien, xxii. pp: 669-726; and “ Die europäischen preys on the larvae of both Cynips glutinosa and its lodger Torymiden," ib. xxiv. pp. 53-142 (abstracted In Cistula enlomologica Synergus facialis. The oak-apple often contains the larvae of Gallmücken," ib. pp. 143-162, and 321-328 ; 1: E. von Bergenstamm
Beiträge zur Kenntnis der Braconidae and Ichneumonidae, which Von Schlechtendal (loc. and P. Löw, “Synopsis Cecidomyidarum," ib. xxvi. pp. 1-104: sup. cit. p. 33) considers to be parasites not on the owner of the Perris, Ann. Soc. Entom. de France, 4th ser. vol. x. pp. 176-1853 gall, Andričus lerminalis, but on inquilinous Tortricidae. Birds R. Osten-Sacken, "On the North American Cecidomyidae," Smith are to be included among the enemies of gall-insects. Oak-galls, berg, Entomologie für Gärtner und Gartenfreunde (Leipzig, 1871):
sonian Miscellaneous Collections, vol. vi. (1867), p.173; E.L. Taschenfor example, are broken open by the titmouse in order to obtain J. W. H. Traill, Scottish Galls," Scollish Naturalist, i. (1871), pp. the grub within, and the " button-galls" of Neurolerus numis-123, &c.; Albert Müller, " British Gall Insects," The Entomologisi's malis, Oliv., are eaten by pheasants.
Annual for 1872, pp. 1-22; B. Altum, Forsizoologic, iii. “ Insecten,' A great variety of deformations and growths produced by pp. 250 seq; (Berlin, 1874.): J. H. Kaltenbach, Die Pflanzenfeinde aus insects and mites as well as by fungi have been described. They and J. Vesque, Les Maladies des plantes cultivées, pp. 98-105, (Paris, are in some cases very slight, and in others form remarkably 1878).
(F. H. B.) large and definite structures. The whole are now included under GALLUPPI, PASQUALE (1770-1846)Italian philosophet, the term Cecidia; a prefix gives the name of the organism to was born on the and of April 1770 at Tropea, in Calabria. He which the attacks are due, c.8. Phytoptocecidia are the galls was of good family, and after studying at the university of Naples formed by Phytoptid mites. Simple galls are those that arise he entered the public service, and was for many years employed when only one member of a plant is involved; compound galls in the office of the administration of finances. At the age of
sixty, having become widely known by his writings on philosophy, For figure and description see Zoology of the “Erebus " and he was called to the chair of logic and metaphysics in the univer"Terror" ii. pp. 46, 47 (1844-1875).
On the mite-galls and their makers, see F. Löw, " Beiträge zur sity of Naples, which he held till his death in November 1846. Naturgesch. der Gallmilben (Phytoptus, Duj.)." Verhandl. d. zoolog. His most important works are: Lellere filosofiche (1827), in which bol. Ges. in Wien, xxiv. (1874). DP: 2-16,
with plate; and " Uber he traces his philosophical development; Elementi di filosofia Milbengallen (Acarocecidien) der Wiener-Gegend," id. pp. 495-508: (1832); Saggio filosofico sulla critica della conoscenza (1819and F. A. W. Thomas, Ältere und neue Beobachiungen über Phyloplo. 1832); Sull' analisi e sulla sintesi (1807); Lesioni di logica e Cecidien (Halle, 1877).
di metafisico (1838–1836); Filosofia della volonld (1832–1842,
incomplete); Storia della filosofia (i., 1842); Considerazioni consul (166), and in the same year reduced the Ligurians to filosofiche sull' idealismo trascendentale (1841), a memoir on the submission. In 164 he was sent as ambassador to Greece and system of Fichte.
Asia, where he held a meeting at Sardis to investigate the charges On his philosophical views see 4. Ferri, Essai sur l'histoire de la brought against Eumenes of Pergamum by the representatives philosophie en Italie au XIXe siècle, i. (1869): V. "Botta
in Uebers of various cities of Asia Minor. Gallus was a man of great learnin Italy," in Mind, ill. (1878): ' v. Lastrucci, Pasquale Galluppi? ing, an excellent Greek scholar, and in his later years devoted Sludio critico (Florence, 1890).
himself to the study of astronomy, on which subject he is quoted GALLUS, CORNELIUS (c. 70-26 B.C.), Roman poet, orator and as an authority by Pliny. politician, was born of humble parents at Forum Julii (Fréjus) 20, De officiis, i. 6. De senectute, 14. Pliny. Nal. Hist. ii. 9.
See Livy, xliv, 37, Epii. 46; Polybius xxxi. 9, 10; Cicero, Brutus, in Gaul. At an early age he removed to Rome, where he was
GALOIS, EVARISTE (1811-1832), French mathematician, was taught by the same master as Virgil and Varius Rufus.. Virgil
, born on the 25th of October 1811, and killed in a duel on the 31st who dedicated one of his eclogues (x.) to him, was in great of May 1832. An obituary notice by his friend Auguste Chevalier measure indebted to the influence of Gallus for the restoration of appeared in the Revue encyclopédique (1832); and his collected his estate. In political life Gallus espoused the cause of Octavi- works are published, Journal de Liouville (1846), pp. 381-444, anus, and as a reward for his services was made praefect of Egypt about fifty of these pages being occupied by researches on the (Suetonius, Augustus, 66). His conduct in this position after- resolubility of algebraic equations by radicals. This branch of wards brought him into disgrace with the emperor, and having algebra he notably enriched, and to him is also due the notion been deprived of his estates and sentenced to banishment, he of a group of substitutions (see EQUATION: Theory of Equations; put an end to his life (Dio Cassius liii. 23). Gallus enjoyed a
also GROUPS, THEORY OF). high reputation among his contemporaries as a man of intellect, His collected works, with an introduction by C. F. Picard, were and Ovid (Tristia, iv, 10) considered him the first of the elegiac published in 1897 at Paris. poets of Rome. He wrote four books of elegies chiefly on his GALSTON, a police burgh and manufacturing town of Ayrshire, mistress Lycoris (a poetical name for Cytheris, a notorious Scotland. Pop. (1901) 4876. . It is situated on the Irvine, s m. actress), in which he took for his model Euphorion of Chalcis. E. by S. of Kilmarnock, with a station on the Glasgow & South(9.0.); he also translated some of this author's works into Latin. Western railway. The manufactures include blankets, lace, Nothing by him has survived; the fragments of the four poems muslin, hosiery and paper-millboard, and coal is worked in the attributed to him (first published by Aldus Manutius in 1590 vicinity. About 1 m. to the north, amid the“ bonnie woods and and printed in A. Riese's Anthologia Latino, 1869) are generally braes," is Loudoun Castle, a seat of the earl of Loudoun. regarded as a forgery.
GALT, SIR ALEXANDER TILLOCH (1817–1893), Canadian See C. Völker, De C. Galli vita et scriptis (1840-1844); A. Nicolas, statesman, was the youngest son of John Galt the author. Born De la vic el des ouvrages de C. Gallus (1851), an exhaustive monograph. in London on the 6th of September 1817, he emigrated to Canada An inscription found at Philae (published 1896) records the Egyptian in 1835, and settled in Sherbrooke, in the province of Quebec, exploits; see M. Schanz, Geschichte der römischen Lilleralur, and Plessis, Poésie latine (1909).
where he entered the service of the British American Land ComGALLUS, GAIUS AELIUS, praefect of Egypt 26-24 B.C. By pany, of which he rose to be chief commissioner. Later he was order of Augustus he undertook an expedition to Arabia Felix, one of the contractors for extending the Grand Trunk railway with disastrous results. The troops suffered greatly from disease, westward from Toronto. He entered public life in 1849 as Liberal heat, want of water and the obstinate resistance of the in- member for the county of Sherbrooke, but opposed the chief habitants. The treachery of a foreign guide also added to his
measure of his party, the Rebellion Losses Bill, and in the same difficulties. After six months Gallus was obliged to return to
year signed a manifesto in favour of union with the United States, Alexandria, having lost the greater part of his force. He was a
believing that in no other way could Protestant and Anglofriend of the geographer Strabo, who gives an account of the Saxon ascendancy over the Roman Catholic French majority in expedition (xvi. pp. 780-782; see also Dio Cassius liii. 29; his native province be maintained. In the same year he retired Pliny, Nal. Hist. vi. 32; C. Merivale, Hist. of the Romans under from parliament but re-entered it in 1853, and was till 1872 the the Empire, ch. 34; H. Krüger, Der Feldzug des A. G. nach chief representative of the English-speaking Protestants of dem glücklichen Arabien, 1862). He has been identified with the Quebec province. On the fall of the Brown-Dorion administra. Aelius Gallus frequently quoted by Galen, whose remedies are
tion in 1858 he was called on to form a ministry, but declined stated to have been used with success in an Arabian expedition.
the task, and became finance minister under Sir John Macdonald GALLUS, GAIUS CESTIUS, governor of Syria during the reign and Sir George Cartier on condition that the federation of the of Nero. When the Jews in Jerusalem, stirred to revolt by the British North American provinces should become a part of their outrages of the Roman procurators, had seized the fortress of programme. From 1858 to 1862 and 1864 to 1867 he was finance Masada and treacherously murdered the garrison of the palace minister, and did much to reduce the somewhat chaotic finances of Herod, Gallus set out from Antioch to restore order. On the of Canada into order. To him are due the introduction of the 17th of November A.D. 66 he arrived before Jerusalem. Having decimal system of currency and the adoption of a system of gained possession of the northern suburb, he attacked the temple protection to Canadian manufactures. To his diplomacy was mount; but, after five days' fighting, júst when (according to due the coalition in 1864 between Macdonald, Brown and Cartier, Josephus) success was within his grasp, he unaccountably with which carried the federation of the British North American drew his forces. During his retreat he was closely pursued by provinces, and throughout the three years of negotiation which the Jews and surrounded in a ravine, and only succeeded in followed his was one of the chief influences. He became finance making good his escape to Antioch by sacrificing the greater minister in the first Dominion ministry, but suddenly and part of his army and a large amount of war
material. Soon after mysteriously resigned on the 4th of November 1867. After his his return Gallus died (before the spring of 67), and was succeeded retirement he gave to the administration of Sir John Macdonald in the governorship by Licinius Mucianus, the prosecution of the a support which grew more and more fitful, and advocated war being entrusted to Vespasian.
independence as the final destiny of Canada: In 1871 he was See Tacitus, llist. ¥. 10, 13: Suetonius, Vespasian, 4: Josephus, again offered the ministry of finance on condition of abandoning Bell. Jud. ii. 14-20; E. Schürer, Hist. of the Jewish People, div. i. these views, but declined. In 1877 he was the Canadian nominee vol. ii. p. 212 (Eng. tr., 1890).
on the Anglo-American fisheries commission at Halifax, and GALLUS, GAIUS SULPICIUS, Roman general, statesman rendered brilliant service. In 1880 he was appointed Canadian and orator. Under Lucius Aemilius Paulus, his intimate friend, high commissioner to Great Britain, but retired in 1883 in favour he commanded the 2nd legion in the campaign against Perseus, of Sir Charles Tupper. During this period he advocated imperial king of Macedonia, and gained great reputation for having pre- federation. He was Canadian delegate at the Paris Monetary dicted an eclipse of the moon on the night before the battle of Conference of 1881, and to the International Exhibition of Pydna (168 B.C.). On his return from Macedonia he was elected | Fisheries in 1883. From this date till his death on the 19th of
September 1893 he lived in retirement. No Canadian statesman | dialect, and preserves much vigorous Doric phraseology fast passhas had sounder or more abundant ideas, but a certain intellectual ing out of use even in country districts. In this novel Mr Galt fickleness made him always a somewhat untrustworthy colleague used, for the first time, the term “ Utilitarian," which afterwards in political life.
(W. L. G.) became so intimately associated with the doctrines of John GALT, JOHN (1770-1839), Scottish novelist, was born at Stuart Mill and Bentham (see Annals of the Parish, chap. xxxv., Irvine, Ayrshire, on the 2nd of May 1779. He received his early and a note by Mill in Utilitarianism, chap. ii.). In Sir Andrew education at Irvine and Greenock, and read largely from one of Wylic the hero entered London as a poor lad, but achieved rethe public libraries while serving as a clerk in a mercantile office.markable success by his shrewd business qualities. The character In 1804 he went to settle in London, where he published anony- is somewhat exaggerated, but excessively amusing. The Entail mously a poem on the Battle of Largs. After unsuccessful was read thrice by Byron and Scott, and is the best of Galt's attempts to succeed in business Galt entered at Lincoln's Inn, longer novels. Leddy Grippy is a wonderful creation, and was but was never called to the bar. He obtained a commission from considered by Byron equal to any female character in literature a British firm to go abroad to find out whether the Berlin and since Shakespeare's time. The Provost, in which Provost Pawkie Milan decrees could be evaded. He met Byron and Sir John tells his own story, portrays inimitably the jobbery, bickerings Hobhouse at Gibraltar, travelled with Byron to Malta, and met and self-seeking of municipal dignitaries in a quaint Scottish him again at Athens. He was afterwards employed by the burgh. In Lawrie Todd Galt, by giving us the Scot in America, Glasgow merchant Kirkman Finlay on similar business at accomplished a feat which Sir Walter never attempted. This Gibraltar, and in 1814 visited France and Holland. His early novel exhibits more variety of style and a greater love of nature works are the Life and Administration of Wolsey, Voyages and than his other books. The life of a settler is depicted with unerring Travels, Lellers from the Levant, the Life of Benjamin West, pencil, and with an enthusiasm and imaginative power much more Historical Pictures and The Wandering Jew; and he induced poetical than any of the author's professed poems. Colburn to publish a periodical containing dramatic pieces The best of Galt's novels were reprinted in Blackwood's Standard rejected by London managers. These were afterwards edited Novels, to volume i. of which his friend Dr Moir prefixed a memoir. by Galt as the New Brilish Theatre, which included some plays of GALT, a town in Waterloo county, Ontario, Canada, 23 m. his own. He first showed his real power as a writer of fiction in N.N.W.of Hamilton, on the Grand river and on the Grand Trunk The Ayrshire Legalees, which appeared in Blackwood's Magazine and Canadian Pacific railways. Pop. (1881) 5187; (1901) 7866. in 1820. This was followed in 1821 by his masterpiece--The It is named after John Galt, the author. It has excellent water Annals of the Parisk; and, at short intervals, Sir Andrew Wylie, privileges which furnish power for flour-mills and for manuThe Entail, The Steam-Boal and The Provost were published. factures of edge tools, castings, machinery, paper and other These humorous studies of Scottish character are all in his industries. happiest manner. His next works were Ringan Gilhaize (1823), GALTON, SIR FRANCIS (1822 ), English anthropologist, a story of the Covenanters; The Spaewife (1823), which relates son of S. T. Galton, of Duddeston, Warwickshire, was born on the to the times of James I. of Scotland; Rothelan (1824), a novel 16th of Februaty 1822. His grandfather was the poet-naturalist founded on the reign of Edward III.; The Omen (1825), which Erasmus Darwin, and Charles Darwin was his cousin. After was favourably criticized by Sir Walter Scott; and The Last attending King Edward VI.'s grammar school, Birmingham, he of the Lairds, another picture of Scottish life.
studied at Birmingham hospital, and afterwards at King's In 1826 he went to America as secretary to the Canada Land College, London, with the intention of making medicine his proCompany. He carried out extensive schemes of colonization, fession; but after taking his degree at Trinity College, Cambridge, and opened up a road through what was inen forest country in 1843 he changed his mind. The years 1845-1846 he spent in between Lakes Huron and Erie. In 1827 he founded Guelph in travelling in the Sudan, and in 1850 he made an exploration, with upper Canada, passing on his way the township of Galt on the Dr John Anderson, of Damaraland and the Ovampo country in Grand river, named after him by the Hon. William Dixon, But south-west Africa, starting from Walfisch Bay. These tracts had all this work proved financially unprofitable to Galt. In 1829 practically never been traversed before, and on the appearance he returned to England commercially a ruined man, and devoted of the published account of his journey and experiences under the himself with great ardour to literary pursuits, of which the first title of Narrative of an Explorer in Tropical South Africa (1853) fruit was Lawrie Todd-one of his best novels. Then came Galton was awarded the gold medal of the Royal Geographical Southennan, a tale of Scottish life in the times of Queen Mary. Society. His Art of Travel; or, Shifts and Contrivances in Wild In 1830 he was appointed editor of the Courier newspaper-a Countries was first published in 1855. In 1860 he visited the post he soon relinquished. His untiring industry was seen in the north of Spain, and published the fruits of his observations of the publication, in rapid succession, of a Life of Byron, Lives of the country and the people in the first of a series of volumes, which Players, Bogle Corbel, Stanley Buxton, The Member, Tke Radical, he edited, entitled Vacation Tourists. He then turned to meteorEben Erskine, The Slolen Child, his Autobiography, and a col- ology, the result of his investigations appearing in Meleorolection of tales entitled Slories of the Study. In 1834 appeared graphica, published in 1863. This work was the first serious his Literary Life and Miscellanies, dedicated by permission to attempt to chart the weather on an extensive scale, and in it also William IV., who sent the author a present of £200. As soon as the author first established the existence and theory of antithis work was published Galt retired to Greenock, where he cyclones. Galton was a member of the meteorological committee continued his literary labours till his death on the 11th of April (1868), and of the Meteorological Council which succeeded it, for 1839.
over thirty years. But his name is most closely associated with Galt, like almost all voluminous writers, was exceedingly studies in anthropology and especially in heredity. In 1869 unequal. His masterpieces are The Ayrshire Legalees, The appeared his Heredilary Genius, its Laws and Consequences, a work Annals of the Parish, Sir Andrew Wylie, The Entail, The Provost which excited much interest in scientific and medical circles. This and Lawrie Todd. The Ayrshire Legatoes gives, in the form of was followed by English Men of Science, their Nature and Nurlure, a number of exceedingly diverting letters, the adventures of the published in 1874; Inquiries into Human Faculty and its DevelopRev. Dr Pringle and his family in London. The letters are made ment, issued in 1883; Life-History Album (1884); Record of the excuse for endless tea-parties and meetings of kirk-session Family Faculties (1884) (tabular forms and directions for enterin the rural parish of Garnock. The Annals of the Parish are ing data, with a preface); and Natural Inheritance (1889). The told by the Rev. Micah Balwhidder, Galt's finest character. This idea that systematic efforts should be made to improve the breed work (which, be it remembered, existed in MS. before Waverley of mankind by checking the birth-rate of the unfit and furtherwas published) is a splendid picture of the old-fashioned Scottish ing the productivity of the fit was first put forward by him in 1865; pastor and the life of a country parish; and, in rich humour, he mooied it again in 1884, using the term "eugenics " for the genuine pathos and truth to nature it is unsurpassed even by first time in Human Faculty, and in 1904 he endowed a research Scott. it is a fine specimen of the homely graces of the Scottish | fellowship in the university of London for the promotion of
knowledge of that subject, which was defined as “the study of documents in the possession of the Institute of Bologna, however, agencics under social control that may improve or impair the it appears that twenty years previous to the publication of his racial qualities of future generations, either physically or men. Commentary Galvani was already engaged in investigations as tally." Galton was the author of memoirs on various an to the action of electricity upon the muscles of frogs. The thropometric subjects; he originated the process of composite observation that the suspension of certain of these animals on an portraiture, and paid much attention to finger-prints and their iron railing by copper hooks caused twitching in the muscles of employment for the identification of criminals, his publications their legs led him to the invention of his metallic arc, the first on this subject including Finger Prints (1892), Decipherment of experiment with which is described in the third part of the Blurred Finger Prints (1893) and Finger Print Direclories (1895), Commenlary, with the date September 20, 1786. The arc he From the Royal Society, of which he was elected a fellow in 1860, constructed of two different metals, which, placed in contact he received a royal medal in 1886 and the Darwin medal in 1902, the one with a frog's nerve and the other with a muscle, caused and honorary degrees were bestowed on him by Oxford (1894) contraction of the latter. In Galvani's view the motions of the and Cambridge (1895). In 1908 he published Memories of My muscle were the result of the union, by means of the metallic arc, Life, and in 1909 he received a knighthood.
of its exterior or negative electrical charge with positive electricity GALUPPI, BALDASSARE (1706-1785), Italian musical com- which proceeded along the nerve from its inner substance. Volta, poser, was born on the 18th of October 1706 on the island of on the other hand, attributed them solely to the effect of Burano near Venice, from which he was often known by the electricity having its source in the junction of the two dissimilar nickname of Buranello. His father, a barber, and violinist at the metals of the arc, and regarded the nerve and muscle simply as local theatre, was his first teacher. His first opera, composed at conductors. On Galvani's refusal, from religious scruples, to the age of sixteen, being hissed off the stage, he determined to take the oath of allegiance to the Cisalpine republic in 1797, he study seriously, and entered the Conservatorio degli Incurabili at 'was removed from his professorship. Deprived thus of the means Venice, as a pupil of Antonio Lotti. After successfully producing of livelihood, he retired to the house of his brother Giacomo, two operas in collaboration with a fellow-pupil, G. B. Pescetti, in where he soon fell into a feverish decline. The republican 1728 and 1729, he entered upon a busy career as a composer of government, in consideration of his great scientific fame, eventuoperas for Venetian theatres, writing sometimes as many as five ally, but too late, determined to reinstate him in his chair, and he in a year. He visited London in 1741, and arranged a pasticcio, died at Bologna on the 4th of December 1798. Alexander in Persia, for the Haymarket. Burney considered his A quarto edition of his works was published at Bologna in 1841influence on English music to have been very powerful. In 1740 1842, by the Academy of Sciences of the Institute of that city, under he became vice-maestro di cappella at St Mark's and maestro in
the title Opere edile ed inedite del professore Luigi Galvani. 1762. In 1749 he began writing comic operas to libretti by GALVANIZED IRON, sheet iron having its surface covered Goldoni, which enjoyed an enormous popularity. He was invited with a thin coating of zinc. In spite of the name, galvanic to Russia by Catherine II. in 1766, where his operas made a action has often no part in the production of galvanized iron, favourable impression, and his influence was also felt in Russian which is prepared by dipping the iron, properly cleaned and church music. He returned to Venice in 1768, where he had held pickled in acid, in a bath of molten zinc. The hotter the zinc the the post of director of the Conservatorio degli Incurabili since thinner the coating, but as a high temperature of the bath is 1762. He died on the 3rd of January 1785.
attended with certain objections, it is a common practice to use a Galuppi's best works are his comic operas, of which Il Filosofo moderate temperature and clear off the excess of zinc by passing di Campagna (1754), known in England as The Guardian Trick'd the plates between rollers. In Norwood and Rogers's process a (Dublin, 1762) was the most popular. His melody is attractive thin coating of tin is applied to the iron before it is dipped in the rather than original, but his workmanship in harmony and zinc, by putting the plates between layers of granulated tin in a orchestration is generally superior to that of his contemporaries. wooden tank containing a dilute solution of stannous chloride, He seems to have been the first to extend the concerted finales of when tin is deposited on them by galvanic action. In “cold Leo and Logroscino into a chain of several separate movements, galvanizing" the zinc is deposited electrolytically from a bath, working up to a climax, but in this respect he is much inferior to preferably kept neutral or slightly acid, containing a 10% Sarti and Mozart.
solution of crystallized zinc sulphate, ZnS0x7H,0. The resulting Browning's poem, "A Toccata of Galuppi,” does not refer to surface is usually duller and less lustrous than that obtained by any known composition, but more probably to an imaginary the use of molten zinc. Another method of forming a coating of extemporization on the harpsichord, such as was of frequent zinc, known as “ sherardizing," was invented by Sherard Cowperoccurrence in the musical gatherings of Galuppi's day.
Coles, who found that metals embedded in zinc dust (a product See also Alfred Wotquerme, Baldassare Galuppi, étude biblio- obtained in zinc manufactureand consisting of metallic zinc mixed graphique sur ses æwres dramatiques (Brussels, 1902). Many of his with a certain amount of zinc oxide) and heated to temperatures autograph scores are in the library of the Brussels conservatoire. well below the melting point of zinc, become coated with a layer
(E. J. D.)
of that metal. In carrying out the process the articles are placed GALVANI, LUIGI (1737-1798), Italian physiologist, after in an air-light vessel with the zinc dust, which must be dry, and whom galvanism received its name, was born at Bologna on the subjected to a heat of 250-330°C., the time for which the heating 9th of September 1737. It was his wish in early life to enter the is continued depending on the thickness of the deposit required church, but by his parents he was educated for a medical career. and varying from one-half to several hours. If an air-tight At the university of Bologna, in which city he practised, he was receptacle is not available, a small percentage of powdered carbon in 1762 appointed public lecturer in anatomy, and soon gained is added to the zinc-dust, to prevent increase in the amount of repute as a skilled though not eloquent teacher, and, chiefly from oxide, which, if present in excess, tends to make the deposit dull. his researches on the organs of hearing and genito-urinary tract Galvanized iron by its zinc surface is protected from corrosion of birds, as a comparative anatomist. His celebrated theory by the weather, though the protection is not very efficient in of animal electricity he enunciated in a treatise, “ De viribus the presence of acid or sulphurous fumes, and accordingly it electricitatis in motu musculari commentarius,” published in the is extensively employed for roofing, especially in the form of 7th volume of the memoirs of the Institute of Sciences at Bologna corrugated sheets. The iron wire used for wire-netting, telein 1791, and separately at Modena in the following year, and graphic purposes, &c., is commonly galvanized, as also are bolts, elsewhere subsequently. The statement has frequently been nuts, chains and other fittings on ships. repeated that, in 1786, Galvani had noticed that the leg of a GALVANOMETER, an instrument for detecting or measuring skinned frog, on being accidentally touched by a scalpel which electric currents. The term is generally applied to instruments had lain near an electrical machine, was thrown into violent which indicate electric current in scale divisions or arbitrary convulsions; and that it was thus that his attention was first units, as opposed to instruments called amperemeters (9.0.), directed to the relations of animal functions to electricity. From I which show directly on a dial'the value of the current in amperes,
429 Galvanometers may be divided into direct current and alternating in the field, so as to set with its axis more nearly parallel to the lines current instruments, according as they are intended to measure mirror; in the latter form it is well represented by several much one or other of these two classes of currents (see ELECTRO- used laboratory instruments. The movable coil galvanometer has KINETICS).
the great advantage that it is not easily disturbed by the magnetic Direct Current Galvanometers.--The principle on which one type fields caused by neighbouring magnets or electric currents, and thus of direct current galvanometer, called a movable needle galvano is especially useful in the electrical workshop and factory. meter, depends for its action is that a small magnet when suspended In the practical construction of the suspended needle fixed coil in the centre of a coil of wire tends to set its magnetic axis in the galvanometer great care must be taken with the insulation of the direction of the magnetic field of the coil at that point due to the wire of the coil. This wire is generally silk-covered, current passing through it. In the other type, or movable coil wound on a frame, the whole being thoroughly saturated
Construc galvanometer, the coil is suspended and the magnet fixed; hence with paraffin wax. In some cases two wires are wound the coil tends to set itself with its axis parallel to the lines of force on in parallel, constituting a " differential galvanometer. of the magnet. The movable system must be constrained in some When properly adjusted this instrument can be used for the exact way to take up and retain a definite position when no current is comparison of electric currents by a null method, because if ats passing by means which are called the control."
electric current is passed In its simple and original form the movable needle galvanometer through one wire and creates consisted of a horizontal magnetic needle suspended within a coil certain deflexions of the Movable of insulated wire by silk fibres or pivoted on a point like needle, the current which
1910mg ca 10 a compass needle. The direction of such a needle is con- annuls this deflexion when Liham Dishes trolled by the direction of the terrestrial magnetic force passed through the other
PRO do salyano within the coil. If the needle is so placed that its axis is wire must be equal to the
Ndois parallel to the plane of the coil, then when an electric cur- first current. In the con
One best rent passes through the coil it is deflected and places itself at an angle struction of a movable coil
Pull bronayla to the axis of the coil determined by the strength of the current | galvanometer, it is usual to and of the controlling field. In the early forms of movable needle intensify the magnetic field galvanometer the needle was either a comparatively large magnet by inserting a fixed soft iron several inches in length, or else a smaller magnet was employed core in the interior of the carrying a long pointer which moved over a scale of degrees so as to movable coil. If the current indicate the deflexion. A method of measuring the deflexion by to be measured is too large
hanno means of a mirror scale and telescope was introduced by K. F. to be passed entirely through Gauss and W. Weber. The magnet had a mirror attached to it, the galvanometer, a portion and a telescope having cross wires in the focus was used to observe is allowed to flow through a the scale divisions of a fixed scale seen reflected in the mirror. Lord circuit connecting the two Mirror
Kelvin (Professor W. Thomson) made the important terminals of the instrument. galvanoimprovement of reducing the size of the needle and attach- This circuit is called a shunt
onts ing it to the back of a very small mirror, the two being and is generally arranged so aeters.
suspended by a single fibre of cocoon silk. The mirror as to take 0-9, 0.99, or 0.999 was made of silvered microscopic glass about in. in diameter, of the total current, leaving Fig. 1.-Kelvin Astatic Mirror Galand the magnetic needle or needles consisted of short fragments of 0-1, 0:or or 0.001 to flow vanometer. Elliott square pattern. watchspring cemented to its back. A ray of light being thrown on the through the galvanometer. mirror from a lamp the deflexions of the needle were observed by W.E.
Ayrton and T. Mather have designed a universal shunt box or watching the movements of a spot of light reflected from it upon
a resistance which can be applied
to any galvanometer and by which a fixed scale. This form of mirror galvanometer was first devised known fraction of any current can be sent through the galvanometer in connexion with submarine cable signalling, but soon became an
when we know its resistance (see Jour. Inst. Elec. Eng. Lond., 1894, indispensable instrument in the physical laboratory.
23, p. 314): A galvanometer can be calibrated, or the meaning of its In course of time both the original form of single needle galvano- deflexion determined, by passing through it an electric current of meter and mirror galvanometer were improved by introducing
the known value and observing the deflexion of the needle or coil. The Astatic
astatic principle and weakening the external controlling known current can be provided in the following manner -a single magnetic field. If two magnetic needles of equal size and secondary cell of any kind can have its electromotive
force measured galvano
moment are attached rigidly to one stem parallel to each by the potentiometer (q.v.), and compared with that of a standard
other but with poles placed in opposite directions an voltaic cell. If the secondary cell is connected with the galvanometer astatic system results; that is, if the needles
are to suspended as through a known high resistance R, and if the galvanometer is to be free to move in a horizontal plane, and if they are made exactly shunted, that is, has its terminals connected by another resistance S equal in magnetic strength, the system will have no directive power, then if the resistance of the galvanometer itself is denoted by G If one needle is slightly weaker than the other, the suspended gold system will set itself with some axis parallel to the lines of force
Tadi.ideal of a field in which it is placed. In a form of astatic needle galvanople
obro meter devised by Professor A. Broca of Paris, the pair of magnetized
Pot needles are suspended vertically and parallel to each other with Sio ALLIOTT SPOIL poles in opposite directions. The upper poles are included in one bi
Sve coil and the lower poles within another coil, so connected that the bitno
lo current circulates in the right direction in each coil to displace the bo pairs of poles in the same direction. By this mode of arrangement
sont a greater magnetic moment can be secured, together with more perfect astaticity and freedom from
disturbance by external fields. The earth's magnetic field can be weakened by means of a controlling magnet arranged to create in the space in the interior of the galvanometer coils an extremely feeble controlling magnetic field. In rom instruments having a coil for each needle and designed so that the current in both coils passes so as to turn both needles in the same direction, the controlling magnet is so adjusted that the normal hasil position of the needles is with the magnetic axis parallel to the plane of the coil. An astatic magnetic system used in conjunction with
po a mirror galvanometer gives a highly sensitive form of instruments
15 tests (fig. 1); it is, however, easily disturbed by stray magnetic fields caused by neighbouring magnets or currents through conductors,
FIG. 2.-Movable Coil Galvanometer. and therefore is not suitable for use in many places.
This fact led to the introduction of the movable coil galvanometer the whole resistance of the shunted galvanometer and high resistance which was first devised by Lord Kelvin as a telegraphic signalling has a value represented by R+GFs, and therefore the current Movable coil
and others into a laboratory galvanometer (fig. 2). In this through the galvanometer produced by an electromotive force E of galvano
instrument a permanent magnet, generally of the horse the cell is represented by
R(G+S)+GS is bifilar, consisting of two fine wires which are connected to the ends Suppose this current produces a deflexion of the needle or coil of the coil and serve to lead the current in and out. If such a coil or spot of light equal to X scale divisions, we can then alter the is placed with its plane parallel to the lines of force of the permanent value of the resistances R and S, and so determine the relation magnet, then when a current is passing through it it displaces itself between the deflexion and the current. By the sensitiveness of the