Chapter 4

See Robert Nisbet Bain,The Pupils of Peter the Great(London, 1895).

(R. N. B.)

DOLHAIN,the most eastern town of Belgium, situated on the Vesdre, N. E. of Verviers and close to the Prussian frontier. Pop. (1904) 4757. It is quite a modern town, occupying the site of the lower town of the ancient city of Limburg, which was destroyed by Louis XIV. in 1675. On a rocky eminence above Dolhain are still to be seen the fine ruins of the old castle of Limburg, the cradle of the ancient family of that name from which sprang the Luxemburg family and several emperors of Germany. The Gothic church of St George of the 13th century has been restored. At a short distance from Dolhain is the famous dam of the Gileppe, the vast reservoir constructed to supply Verviers with water free from lime for its cloth manufactures. The aqueduct from Gileppe to Verviers is nearly 5½ m. in length.

DOLICHOCEPHALIC(long-headed), a term invented by Andreas Retzius to denote (as opposed to “brachycephalic”) those skulls the diameter of which from side to side, or the transverse diameter, is small in comparison with the longitudinal diameter or that from front to back. Retzius, though inventing the term, did not define it precisely. Paul Broca applied it to skulls having a cephalic index of seventy-five and under, and this limit is generally adopted. Dolichocephaly, according to Retzius, was the distinctive cranial feature of the earliest inhabitants of Europe. To-day it is characteristic of the negro races, of thePapuans, the Polynesians and the Australians, though among the negritos and some of the pigmy races of Africa brachycephalic skulls are the rule. Of the yellow races the Eskimo is the most dolichocephalic. Of white races the Arabs and Kabyles of Algeria, and the Guanchos of the Canary Islands, are most notable for dolichocephalic tendency. Dolichocephaly is sometimes frontal, as among adult whites, sometimes occipital or confined to the back of the head, as among inferior negro-races, Australians, Papuans and newly-born whites.

DOLL,a child’s plaything in the shape of a human figure or taken as representing one. The word “doll” was not in common use in the middle ages, “children’s babies” and other terms being substituted for it; the commonly accepted view is that it is abbreviated from the name Dorothy (cf. Scottish “Doroty”). “Idol” has also been connected with it; but the accent is held to tell against this. Another derivation is from Norsedaul(woman), with which may be compared O.H.G.toccha, M.H.G.docke, a girl, doll, used also in the sense of butterfly, nightmare, &c., thus connecting the doll with magic and superstition. The same connexion is found in Asia Minor, South India, among the Pueblo peoples and in South Africa; philology apart, therefore, the derivation from “idol” has much to recommend it, and some side influence from this word may well have caused the selection of the form “doll.” Dolls proper should be distinguished from (a) idols, (b) magical figurines, (c) votive offerings, (d) costume figures. The festival figures of Japan, like the bambino of Italy, given to the child only on certain saints’ days, hardly come within the category of dolls.

Dolls were known in ancient Egypt (XVIIIth Dynasty) and Asia Minor; they were common both in Greece and Rome; Persius mentions that girls vowed them to Venus when they got married; dolls found in the catacombs are preserved in the Vatican and the Museum Carpegna. Theνευρόσπαστον(Lat.crepundia) of Greek finds of the 6th and later centuriesb.c.was a marionette. Dolls were in use among the Arabs at the time of Mahomet, and the prophet’s nine-year-old wife Ayesha is said to have induced him to join her in her play with them. Although Mahommedanism prohibits the making of figures in human shape, dolls do not seem to have disappeared from Mahommedan countries, though substitutes for them are perhaps more common there than elsewhere.

Dolls are extremely common in Africa. There seem to be forms peculiar to different regions, such as the flat, spade-shaped figure on the Gold Coast. Among the Wasaramo the girls carry from the age of puberty till the birth of their first child an object indistinguishable from the ordinary doll; it is calledmwana ya kiti(stool-child) because it is placed on a stool at home; it probably has a magical significance. The same may be said of the Australian figurines; others, made of cane, are undoubtedly children’s dolls; excellently moulded wax figures are also found. In Asia dolls properly so-called are apparently rare; but there are specimens in museums from the Malay peninsula, Persia and South India, and in Asia Minor children use cushions, &c., as surrogates. They are found in Alaska among the Eskimo. Most Red Indian tribes had them; a mother who has lost her child carries its dolls and other playthings. Cortes is said to have found Montezuma and his court playing with elaborate dolls; they have been dug up from prehistoric Peruvian graves. In the Gran Chaco metacarpal bones of the rhea are in use, wrapped in a blanket when they represent male, in a petticoat when they are female.

But little attention has been paid to the psychological side of dolls. Though many boys play with them, dolls are mainly confined to girls; and female dolls predominate in the proportion of twelve to one. The culmination of the doll instinct is between the age of eight and nine; but they are not entirely dropped till much later; in fact unmarried and childless women sometimes keep it up for years. In children it is said by Hall to be by no means always a manifestation of the maternal instinct; for dolls are not always regarded as children, and the proportion of adults increases with the age of the children. But the important point is whether the child regarded itself as older or younger than the doll. There is, on the other hand, a tendency to neglect dolls for babies and a reverse current of love of dolls which arises out of love of babies.

Bibliography.—For a list of works see A. MacDonald,Man and Abnormal Man(U. S. Senate Document, 1905, vol. ix. No. 187, p. 275); see also Andree,Ethnographische ParallelenN. F.; Schlegel,Indische Bibliothek. i. 139;Brandenburgia, xi. 28;Delineator, lviii. 927;Globus, lxxv. 354, lxxx. 205;Internat. Archiv f. Ethnog.vii. 45;Ladies’ Home Journ.xvi.;Westermann’s Monatshefte(Feb. 1899, &c.);Man(1903, No. 22). For the psychological side seePaedagogical Seminary, iv. 129, discussed inContemporary Rev.lxxv. 58; Mrs F. H. Burnett, “The One I know best of all”; Sully,Studies of Childhood; G. Sand,Histoire de ma vie.

(N. W. T.)

DOLLAR,a town of Clackmannanshire, Scotland, 6 m. N.E. of Alloa by the North British railway, not far from the Devon. Pop. (1901) 1619. The village, which is beautifully situated, contains several handsome stone villas occupied by families attracted to the town by its educational facilities. The academy, housed in a fine mass of buildings of the Grecian order (opened about 1819), was founded by Captain John McNab (1732-1802), a native who began life as a herdboy, and afterwards became a rich shipowner. From the burn of Dollar (or Dolour), which runs through the ravine of Dollar Glen, the town draws its water-supply. On an isolated hill above the junction of the parent streams, named Sorrow and Care, stands the ruin of Castle Campbell, known also as Gloom Castle, an old stronghold of the Argyll family. The castle was burned by the Macleans in 1644, in the interest of the marquess of Montrose, and not again restored. Although a ruin it is carefully preserved. The Rev. Dr James Aitken Wylie (1808-1890), the historian of Protestantism, was a minister in Dollar for several years. Patrick Gibson, the etcher and landscape-painter, was drawing-master at the academy from 1824 to 1829, and William Tennant, the author ofAnster Fair, was a teacher of classics from 1819 till 1834, when he was appointed to the chair of Hebrew in St Andrews University. Harviestoun Castle, about midway between Dollar and Tillicoultry, once belonged to the Tait family, and here Archibald Campbell Tait, archbishop of Canterbury, spent some of his boyhood.

DOLLAR,a silver coin at one time current in many European countries, and adopted under varying forms of the name elsewhere. The word “dollar” is a modified form ofthaler, which, with the variant forms (daler, dalar, daalder, tallero, &c.), is said to be a shortened form ofJoachimsthaler. ThisJoachimsthalerwas the name given to a coin intended to be the silver equivalent of the gold gulden, a coin current in Germany from the 14th century. In 1516 a rich silver mine was discovered in Joachimsthal (Joachim’s dale), a mining district of Bohemia, and the count of Schlitz, by whom it was appropriated, caused a great number of silver coins to be struck (the first having the date 1518), bearing an effigy of St Joachim, hence the name. TheJoachimsthalerwas also sometimes known as theSchlickenthaler. The first use of the word dollar in English was as applied to this silver coin, the thaler, which was current in Germany at various values from the 16th century onwards, as well as, more particularly, to the unit of the German monetary union from 1857 to 1873, when the mark was substituted for the thaler. The Spanish piece-of-eight (reals) was also commonly referred to as a dollar. When the Bank of England suspended cash payments in 1797, and the scarcity of coin was very great, a large number of these Spanish coins, which were held by the bank, were put into circulation, after having been countermarked at the Mint with a small oval bust of George III., such as was used by the Goldsmiths’ Company for marking plate. Others were simply overstamped with the initials G.R. enclosed in a shield. In 1804 the Maundy penny head set in an octagonal compartment was employed. Several millions of these coins were issued. These Spanish pieces-of-eight were also current in the Spanish-American colonies, and were very largely used in the British North American colonies. As the reckoning was by pounds, shillings and pence in the British-American colonies, great inconveniences naturally arose, but these were to some extent lessened by the adoption of a tariff list, by which the various gold and silver coins circulatingwere rated. In 1787 the dollar was introduced as the unit in the United States, and it has remained as the standard of value either in silver or gold in that country. For the history of the various changes in the weights and value of the coin seeNumismatics. The Spanish piece-of-eight was also the ancestor of the Mexican dollar, the Newfoundland dollar, the British dollar circulating in Hong Kong and the Straits Settlements, and the dollar of the South American republics, although many of them are now dollars only in name.

DOLLING, ROBERT WILLIAM RADCLYFFE(1851-1902), English divine, known as Father Dolling, was born at Magheralin, Co. Down, and educated at Harrow and Cambridge. From 1878 to 1882 he was warden of one of the houses of the Postmen’s League, started by Father Stanton of St Alban’s, Holborn. He was ordained in 1883 to a curacy at Corscombe, Dorset, but resided in London as head of St Martin’s mission, Stepney. In 1885 a difficulty as to the relation of his mission to Holy Trinity parish, Stepney, led to his resignation, and he next accepted the charge of St Agatha’s, Landport, the Winchester College mission. The remarkable reforms he accomplished there may be ascertained from hisTen years in a Portsmouth slum(London 1896). In 1885 he again resigned, owing to the bishop of Winchester’s refusal to sanction the extreme ritual used in the service at St Agatha’s. In 1897 he visited America, where his preaching made a great impression. He returned to England in the following year as vicar of St Saviour’s, Poplar, and retained that living until his death.

An account of Dolling’s person and missionary work among the poor is given inThe Life of Father Dolling(London, 1903), by the Rev. C. E. Osborne.

DÖLLINGER, JOHANN JOSEPH IGNAZ VON(1799-1890), German theologian and church historian, was born at Bamberg, Bavaria, on the 28th of February 1799. He came of an intellectual stock, his grandfather and father having both been physicians of eminence and professors of one or other of the branches of medical science; his mother too belonged to a family not undistinguished in intellectual power. Young Döllinger was first educated in the gymnasium at Wurzburg, and then began to study natural philosophy at the university in that city, where his father now held a professorship. In 1817 he began the study of mental philosophy and philology, and in 1818 turned to the study of theology, which he believed to lie beneath every other science. He particularly devoted himself to an independent study of ecclesiastical history, a subject very indifferently taught in Roman Catholic Germany at that time. In 1820 he became acquainted with Victor Aimé Huber (1800-1869), a fact which largely influenced his life. On the 5th of April 1822 he was ordained priest, after studying at Bamberg, and in 1823 he became professor of ecclesiastical history and canon law in the lyceum at Aschaffenburg. He then took his doctor’s degree, and in 1826 became professor of theology at Munich, where he spent the rest of his life. About this time Döllinger brought upon himself the animadversion of Heine, who was then editor of a Munich paper. The unsparing satirist described the professor’s face as the “gloomiest” in the whole procession of ecclesiastics which took place on Good Friday.

It has been stated that in his earlier years Döllinger was a pronounced Ultramontane. This does not appear to have been altogether the case; for, very early in his professorial career at Munich, the Jesuits attacked his teaching of ecclesiastical history, and the celebrated J. A. Möhler (q.v.) who afterwards became his friend, on being appealed to, pronounced on the whole in his favour. He also entered into relations with the well-known French Liberal Catholic Lamennais, whose views on the reconciliation of the Roman Catholic Church with the principles of modern society had aroused much suspicion in Ultramontane circles. In 1832 Lamennais, with his friends Lacordaire and Montalembert, visited Germany, and obtained considerable sympathy in their attempts to bring about a modification of the Roman Catholic attitude to modern problems. Döllinger seems to have regarded favourably the removal, by the Bavarian government, in 1841, of Professor Kaiser from his chair, because he had taught the infallibility of the pope. On the other hand, he published a treatise in 1838 against mixed marriages, and in 1843 wrote strongly in favour of requiring Protestant soldiers to kneel at the consecration of the Host when compelled officially to be present at Mass. Moreover, in his works onThe Reformation(3 vols. Regensburg, 1846-1848) and onLuther(1851, Eng, tr., 1853) he is very severe on the Protestant leaders, and he also accepts, in his earlier works, the Ultramontane view then current on the practical condition of the Church of England, a view which in later days he found reason to change. Meanwhile he had visited England, where he was well received; and he afterwards travelled in Holland, Belgium and France, acquainting himself with the condition and prospects of the Roman Catholic Church. In 1842 he entered into correspondence with the leaders of the Tractarian movement in England, and some interesting letters have been preserved which were exchanged between him and Pusey, Gladstone and Hope Scott. When the last-named joined the Church of Rome he was warmly congratulated by Döllinger on the step he had taken. He, however, much regretted the gradual and very natural trend of his new English allies towards extreme Ultramontane views, of which Archdeacon, afterwards Cardinal, Manning ultimately became an enthusiastic advocate. In 1845 Döllinger was made representative of his university in the second chamber of the Bavarian legislature. In 1847, in consequence of the fall from power of the Abel ministry in Bavaria, with which he had been in close relations, he was removed from his professorship at Munich, but in 1849 he was invited to occupy the chair of ecclesiastical history. In 1848, when nearly every throne in Europe was shaken by the spread of revolutionary sentiments, he was elected delegate to the national German assembly at Frankfort,—a sufficient proof that at this time he was regarded as no mere narrow and technical theologian, but as a man of wide and independent views.

It has been said that his change of relations to the Papacy dated from the Italian war in 1859, but no sufficient reason has been given for this statement. It is more probable that, like Grosseteste, he had imbibed in early youth an enthusiastic sentiment of attachment to the Papacy as the only centre of authority, and the only guarantee for public order in the Church, but that his experience of the actual working of the papal system (and especially a visit to Rome in 1857) had to a certain extent convinced him how little correspondence there was between his ideal and the reality. He may also have been unfavourably impressed with the promulgation by Pius IX. in 1854 of the dogma of the Immaculate Conception of the Blessed Virgin. But whatever may have been his reasons, he ultimately became the leader of those who were energetically opposed to any addition to, or more stringent definition of, the powers which the Papacy had possessed for centuries. In some speeches delivered at Munich in 1861 he outspokenly declared his view that the maintenance of the Roman Catholic Church did not depend on the temporal sovereignty of the pope. His book onThe Church and the Churches(Munich, 1861) dealt to a certain extent with the same question. In 1863 he invited 100 theologians to meet at Malines and discuss the question which Lamennais and Lacordaire had prematurely raised in France, namely, the attitude that should be assumed by the Roman Catholic Church towards modern ideas. His address to the assembled divines was “practically a declaration of war against the Ultramontane party.” He had spoken boldly in favour of freedom for the Church in the Frankfort national assembly in 1848, but he had found the authorities of his Church claiming a freedom of a very different kind from that for which he had contended. The freedom he claimed for the Church was freedom to manage her affairs without the interference of the state; the champions of the papal monarchy, and notably the Jesuits, desired freedom in order to put a stop to the dissemination of modern ideas. The addresses delivered in the Catholic congress at Malines were a declaration in the direction of a Liberal solution of the problem of the relations of Church and State. The pope for a moment seemed to hesitate, but there could be little doubt what course he would ultimately pursue, and after four days’ debate the assembly was closed at his command. On the 8th of December 1864 Pius IX. issuedthe famousSyllabus, in which he declared war against modern science and progress (seeSyllabus). It was in connexion with this question that Döllinger published hisPast and Present of Catholic Theology(1863) and hisUniversities Past and Present(Munich, 1867).

We now approach the critical period of Döllinger’s life. It was about this time that some of the leading theologians of the Roman Catholic Church, conceiving that the best way of meeting present perils was to emphasize, as well as to define more clearly, the authority of the pope, advised him to make his personal infallibility a dogma of the Church, and urged strenuously on him the necessity of calling a council for that purpose. There was considerable opposition in various quarters. Many bishops and divines considered the proposed definition a false one. Others, though accepting it as the truth, declared its promulgation to be inopportune. But the headquarters of the opposition was Germany, and its leader was Döllinger, whose high reputation and vast stores of learning placed him far above any other member of the band of the theological experts who now gathered around him. Among them were his intimate friends Johann Friedrich (q.v.) and J. N. Huber, in Bavaria. In the rest of Germany he found many supporters, chiefly professors in the Catholic faculty of theology at Bonn: among these were the famous canonist von Schulte, Franz Heinrich Reusch, the ecclesiastical historian Joseph Langen, as well as J. H. Reinkens, afterwards bishop of the Old Catholic Church in Germany, Knoodt, and other distinguished scholars. In Switzerland, Professor Edward Herzog, who became Old (or, as it is sometimes called, Christ-) Catholic bishop in Switzerland, and other learned men supported the movement. Early in 1869 the famousLetters of Janus(which were at once translated into English; 2nd ed.Das Papsttum, 1891) began to appear. They were written by Döllinger in conjunction with Huber and Friedrich, afterwards professor at Munich. In these the tendency of theSyllabustowards obscurantism and papal despotism, and its incompatibility with modern thought, were clearly pointed out; and the evidence against papal infallibility, resting, as theLettersasserted, on the False Decretals, and accepted without controversy in an age of ignorance, was ably marshalled for the guidance of the council. When, on the 8th of December 1869, it had actually assembled, the world was kept informed of what was going on in theLetters of Quirinus, written by Döllinger and Huber while the debates of the council were proceeding. Some of these letters appeared in the German newspapers, and an English translation was published by Rivington. Augustin Theiner, the librarian at the Vatican, then in disgrace with the pope for his outspoken Liberalism, kept his German friends well informed of the course of the discussions. The proceedings of the council were frequently very stormy, and the opponents of the dogma of infallibility complained that they were not unfrequently interrupted, and that endeavours were made to put them down by clamour. The dogma was at length carried by an overwhelming majority, and the dissentient bishops, who—with the exception of two—had left the council before the final division, one by one submitted (seeVatican Council). Döllinger, however, was not to be silenced. He headed a protest by forty-four professors in the university of Munich, and gathered together a congress at Nuremberg, which met in August 1870 and issued a declaration adverse to the Vatican decrees. An immense ferment took place. In Bavaria, where Döllinger’s influence was greatest, the strongest determination to resist the resolutions of the council prevailed. But the authority of the council was held by the archbishop of Munich to be paramount, and he called upon Döllinger to submit. Instead of submitting, Döllinger, on the 28th of March 1871, addressed a memorable letter to the archbishop, refusing to subscribe the decrees. They were, he said, opposed to Holy Scripture, to the traditions of the Church for the first 1000 years, to historical evidence, to the decrees of the general councils, and to the existing relations of the Roman Catholic Church to the state in every country in the world. “As a Christian, as a theologian, as an historian, and as a citizen,” he added, “I cannot accept this doctrine.”

The archbishop replied by excommunicating the disobedient professor. This aroused fresh opposition. Döllinger was almost unanimously elected rector-magnificus of the university of Munich, and Oxford, Edinburgh and Marburg universities conferred upon him the honorary degree of doctor of laws and Vienna that of philosophy. The Bavarian clergy invited Bishop Loos of the Jansenist Church in Holland, which for more than 150 years had existed independent of the Papacy and had adopted the name of “Old Catholic,” to hold confirmations in Bavaria. The offer was accepted, and the bishop was received with triumphal arches and other demonstrations of joy. The three Dutch Old Catholic bishops declared themselves ready to consecrate a bishop, if it were desired. The momentous question was discussed at a meeting of the opponents of the Vatican decrees, and it was resolved to elect a bishop and ask the Dutch bishops to consecrate him. Döllinger, however, voted against the proposition, and withdrew from any further steps towards the promotion of the movement. This was the critical moment in the history of the resistance to the decrees. Had Döllinger, with his immense reputation as a scholar, as a divine and as a man, allowed himself to be consecrated bishop of the Old Catholic Church, it is impossible to say how wide the schism would have been. But he declined to initiate a schism. His refusal lost Bavaria to the movement; and the number of Bavarian sympathizers was still further reduced when the seceders, in 1878, allowed their priests to marry, a decision which Döllinger, as was known, sincerely regretted. The Old Catholic Communion, however, was formally constituted, with Reinkens at its head as bishop, and it still continues to exist (seeOld Catholics).

Döllinger’s attitude to the new community was not very clearly defined. It may be difficult to reconcile the two declarations made by him at different times: “I do not wish to join a schismatic society; I am isolated,” and “As for myself, I consider that I belong by conviction to the Old Catholic community.” The latter declaration was made some years after the former, in a letter to Pastor Widmann. The nearest approach to a reconciliation of the two statements would appear to be that while, at his advanced age, he did not wish to assume the responsibility of being head of a new denomination, formed in circumstances of exceptional difficulty, he was unwilling to condemn those who were ready to hazard the new departure. “By conviction” he belonged to the Old Catholics, but he never formally joined them. Yet at least he was ready to meet their leaders, to address them, and to discuss difficult problems with them. His addresses on the reunion of the Churches, delivered at the Bonn Conference of 1872, show that he was by no means hostile to the newly formed communion, in whose interests these conferences were held. In 1874 and again in 1875, he presided over the Reunion Conferences held at Bonn and attended by leading ecclesiastics from the British Isles and from the Oriental Church, among whom were Bishop Christopher Wordsworth of Lincoln; Bishop Harold Browne of Ely; Lord Plunket, archbishop of Dublin; Lycurgus, archbishop of Syros and Tenos; Canon Liddon; and Professor Ossinine of St Petersburg. At the latter of these two conferences, when Döllinger was seventy-six years of age, he delivered a series of marvellous addresses in German and English, in which he discussed the state of theology on the continent, the reunion question, and the religious condition of the various countries of Europe in which the Roman Catholic Church held sway. Not the least of his achievements on this occasion was the successful attempt, made with extraordinary tact, ability, knowledge and perseverance, to induce the Orientals, Anglicans and Old Catholics present to accept a formula of concord, drawn from the writings of the leading theologians of the Greek Church, on the long-vexed question of the Procession of the Holy Spirit. This result having been attained, he passed the rest of his days in retirement, emerging sometimes from his retreat to give addresses on theological questions, and also writing, in conjunction with his friend Reusch, his last book,Geschichte der Moralstreitigkeiten in der römisch-katholischen Kirche seit dem sechzehnten Jahrhundert mit Beiträgen zur Geschichte und Charakteristik des Jesuitenordens(Nordlingen, 1889), in which he deals with the moral theology of St Alfonso de’ Liguori. He diedin Munich, on the 14th of January 1890, at the age of ninety-one. Evenin articulo mortishe refused to receive the sacraments from the parish priest at the cost of submission, but the last offices were performed by his friend Professor Friedrich.

In addition to the works referred to in the foregoing sketch, we may mentionThe Eucharist in the First Three Centuries(Mainz, 1826); aChurch History(1836, Eng. trans. 1840);Hippolytus and Callistus(1854, Eng. trans., 1876);First Age of Christianity(1860);Lectures on the Reunion of the Churches;The Vatican Decrees; Studies in European History(tr. M. Warre, 1890);Miscellaneous Addresses(tr. M. Warre, 1894).SeeLifeby J. Friedrich (3 vols. 1899-1901); obituary notice inThe Times, 11th January 1890; L. von Kobell,Conversations of Dr Döllinger(tr. by K. Gould, 1892).

SeeLifeby J. Friedrich (3 vols. 1899-1901); obituary notice inThe Times, 11th January 1890; L. von Kobell,Conversations of Dr Döllinger(tr. by K. Gould, 1892).

(J. J. L.*)

DOLLOND, JOHN(1706-1761), English optician, was the son of a Huguenot refugee, a silk-weaver at Spitalfields, London, where he was born on the 10th of June 1706. He followed his father’s trade, but found time to acquire a knowledge of Latin, Greek, mathematics, physics, anatomy and other subjects. In 1752 he abandoned silk-weaving and joined his eldest son, Peter Dollond (1730-1820), who in 1750 had started in business as a maker of optical instruments. His reputation grew rapidly, and in 1761 he was appointed optician to the king. In 1758 he published an “Account of some experiments concerning the different refrangibility of light” (Phil. Trans., 1758), describing the experiments that led him to the achievement with which his name is specially associated, the discovery of a means of constructing achromatic lenses by the combination of crown and flint glasses. Leonhard Euler in 1747 had suggested that achromatism might be obtained by the combination of glass and water lenses. Relying on statements made by Sir Isaac Newton, Dollond disputed this possibility (Phil. Trans., 1753), but subsequently, after the Swedish physicist, Samuel Klingenstjerna (1698-1765), had pointed out that Newton’s law of dispersion did not harmonize with certain observed facts, he began experiments to settle the question. Early in 1757 he succeeded in producing refraction without colour by the aid of glass and water lenses, and a few months later he made a successful attempt to get the same result by a combination of glasses of different qualities (seeTelescope). For this achievement the Royal Society awarded him the Copley medal in 1758, and three years later elected him one of its fellows. Dollond also published two papers on apparatus for measuring small angles (Phil. Trans., 1753, 1754). He died in London, of apoplexy, on the 30th of November 1761.

An account of his life, privately printed, was written by the Rev. John Kelly (1750-1809), the Manx scholar, who married one of his granddaughters.

DOLMAN(from Turk.dōlāmān), originally a long and loose garment left unfastened in front, and with narrow sleeves. It is worn generally by the Turks, and is not unlike a cassock in shape. The name was given to the uniform jacket, worn by hussars, and slung from the shoulders with the sleeves hanging loose; and it is also used for a similar garment worn by ladies, with wide cape-like arrangements instead of sleeves.

DOLNJA TUZLA,orDonji Soli, the capital of the Dolnja Tuzla district, in Bosnia, beautifully situated on the Jala or Julla, a small stream flowing into the Spreča, which joins the Bosna at Doboj, 39 m. W.N.W.; and on a branch railway from Doboj. Pop. (1895) 10,227; almost all, including a permanent colony of gipsies, being Moslems. Dolnja Tuzla is the seat of a district court and an Orthodox bishop; with several churches, many mosques, a hospital, gymnasium and commercial school. Besides large alkali works, it has a vigorous trade in grain, livestock, timber and coal, from the surrounding hills, where there is a colony of Hungarian miners; while the salt springs, owned by the state both at Dolnja, or Lower, and Gornja, or Upper Tuzla, 6 m. E., are without a rival in the Balkan Peninsula.

Dolnja Tuzla was called by the RomansAd Salinas. Constantine Porphyrogenitus mentions it, in the 10th century, asSalenes; in other medieval documents it appears asSou,SoworSoli. Its modern name is derived from the Turkishtuz, “salt.” In 1690 the Austrians routed the Turks at Gornja Tuzla, and removed the Franciscan friars, with about 3000 other Roman Catholics, into Slavonia.

DOLOMIEU, DÉODAT GUY SILVAIN TANCRÈDE GRATET DE(1750-1801), French geologist and mineralogist, was born at Dolomieu, near Tour-du-Pin, in the department of Isère in France, on the 24th of June 1750. He was admitted in his infancy a member of the Order of Malta. In his nineteenth year he quarrelled with a knight of the galley on which he was serving, and in the duel that ensued killed him. He was condemned to death for his crime, but in consideration of his youth the grand master granted him a pardon, which, at the instance of Cardinal Torrigiani, was confirmed by Pope Clement XIII., and after nine months’ imprisonment he was set at liberty. Throughout that period he had solaced himself with the study of the physical sciences, and during his subsequent residence at Metz he continued to devote himself to them. In 1775 he published hisRecherches sur la pesanteur des corps à differentes distances du centre de la terre, and two Italian translations of mineralogical treatises by A. F. Cronstedt (1702-1765) and T. O. Bergman (1735-1784). These works gained for him the honour of election as a corresponding member of the Académie des Sciences at Paris. To obtain leisure to follow his favourite pursuits Dolomieu now threw up the commission which, since the age of fifteen, he had held in the carabineers, and in 1777 he accompanied thebailli(afterwards Cardinal L. R. E.) de Rohan to Portugal. In the following year he visited Spain, and in 1780 and 1781 Sicily and the adjacent islands. Two months of the year 1782 were spent in examining the geological structure of the Pyrenees, and in 1783 the earthquake of Calabria induced him to go to Italy. The scientific results of these excursions are given in hisVoyage aux îles de Lipari(1783);Mémoire sur le tremblement de terre de la Calabre(1784);Mémoire sur les îles Ponces, et catalogue raisonné des produits de l’Etna(1788) and other works. In 1789 and 1790 he busied himself with an examination of the Alps, his observations on which form the subject of numerous memoirs published in theJournal de physique. The mineraldolomite, which was named after him, was described by Dolomieu in 1791. He returned to France in that year, bringing with him rich collections of minerals. On the 14th of September 1792 the duc de la Rochefoucauld, with whom he had been for twenty years on terms of the closest intimacy, was assassinated at Forges, and Dolomieu retired with the widow and daughter of the duke to their estate of Roche Guyon, where he wrote several important scientific papers. The events of the 9th Thermidor (July 27, 1794) having restored the country to some tranquillity, Dolomieu recommenced his geological tours, and visited various parts of France with which he had been previously unacquainted. He was in 1796 appointed engineer and professor at the school of mines, and was chosen a member of the Institute at the time of its formation. At the end of 1797 he joined the scientific staff which in 1798 accompanied Bonaparte’s expedition to Egypt. He had proceeded up the Nile as far as Cairo when ill-health made his return to Europe necessary, and on the 7th of March 1799 he set sail from Alexandria. His ship proving unseaworthy put into Taranto, and as Naples was then at war with France, all the French passengers were made prisoners. On the 22nd of May they were carried by ship to Messina, whence, with the exception of Dolomieu, they embarked for the coast of France. Dolomieu had been an object of the hatred of the Neapolitan court since 1783, when he revealed to the grand master of his order its designs against Malta, and the calumnies of his enemies on that island served now as a pretext for his detention. He was confined in a pestilential dungeon, where, clothed in rags, and having nothing but a little straw for a bed, he languished during twenty-one months. Dolomieu, however, did not abandon himself to despair. Deprived of writing materials, he made a piece of wood his pen, and with the smoke of his lamp for ink he wrote upon the margins of a Bible, the only book he still possessed, his treatiseSur la philosophie minéralogique et sur l’espèce minérale(1801). Friends entreated, but in vain, for his liberty; it was with difficulty that they succeeded in furnishing him with a little assistance, and it was only by virtue of a special clause in the treaty between France and Naples that, on the 15th of March 1801, he was released. On his arrival in France he commenced the duties of the chair of mineralogy at the museumof natural history, to which, after the death of Daubenton, he had been elected in January 1800. His course of lectures concluded, he revisited Switzerland. Returning thence he reached the residence of his brother-in-law at Château-Neuf, in the department of Saône-et-Loire, where he was seized with a fever, to which in a few days he succumbed, on the 26th of November 1801.

Dolomieu’s geological theories are remarkable for originality and boldness of conception. The materials constituting the primordial globe he held to have arranged themselves according to their specific gravities, so as to have constituted a fluid central sphere, a solid crust external to this, next a stratum of water, and lastly the atmosphere. Where water penetrated through the crust, solidification took place in the underlying fluid mass, which enlarging in consequence produced rifts in the superincumbent rocks. Water rushing down through the rifts became decomposed, and the resulting effervescence occasioned submarine volcanoes. The crust of the earth he believed to be continually increasing in thickness, owing to the deposition of aqueous rocks, and to the gradual solidification of the molten interior, so that the volcanic eruptions and other geological phenomena of former must have been of far greater magnitude and frequency than those of recent times.

See Lacépède, “Éloge historique de Dolomieu,” inMémoires de la classe des sciences de l’Institut(1806); Thomson, inAnnals of Philosophy, vol. xii. p. 161 (1808).

DOLOMITE,a mineral species consisting of calcium and magnesium carbonate, CaMg(CO3)2, and occurring as rhombohedral crystals or large rock-masses. Analyses of most well-crystallized specimens correspond closely with the above formula, the two carbonates being present in equal molecular proportions (CaCO3, 54.35; MgCO3, 45.65%). Normal dolomite is thus not an isomorphous mixture of calcium and magnesium carbonates, but a double salt; and any variations in composition are to be explained by the isomorphous mixing of this double salt with carbonates of calcium, iron, magnesium, manganese, and rarely of zinc and cobalt.

In crystalline form dolomite is very similar to calcite, belonging to the same group of rhombohedral carbonates; the primitive rhombohedron,r(100), parallel to the faces of which there are perfect cleavages, has interfacial angles of 73° 45′, the angle of the cleavage rhombohedron of calcite being 74° 55′. A specially characteristic feature is that this rhombohedron is frequently the only form present on the crystals (in calcite it is rare except in combination with other forms); the faces are also usually curved (fig. 1), sometimes to an extraordinary degree giving rise to saddle-shaped crystals (fig. 2). Crystals with plane faces are usually twinned, there being an interpenetration of two rhombohedra with the vertical axes parallel. The secondary twin-lamination, parallel to the obtuse rhombohedrone(110), so common in calcite, does not exist in dolomite. In the degree of symmetry possessed by the crystals there is, however, an important difference between calcite and dolomite; the former has the full number of planes and axes of symmetry of a rhombohedral crystal, whilst the latter is hemihedral with parallel faces, having only an axis of triad symmetry and a centre of symmetry. This lower degree of symmetry, which is the same as that of dioptase and phenacite, is occasionally shown by the presence of an obliquely placed rhombohedron, and also by the want of symmetry in the etching and elasticity figures on the faces of the primitive rhombohedron.

Dolomite is both harder (H. = 3½-4) and denser (sp. gr. 2.85) than calcite. The two minerals may also be readily distinguished by the fact that dolomite is not acted upon by cold, dilute acids (see below,Dolomite Rock). Crystals of dolomite vary from transparent to translucent, and often exhibit a pearly lustre, especially when the faces are curved; the colour is usually white or yellowish.

The crystallized mineral was first examined chemically by P. Woulfe in 1779, and was named compound-spar by R. Kirwan in 1784; other early names are bitter-spar, rhomb-spar and pearl-spar (but these included other rhombohedral carbonates). The name dolomite (dolomieof N. T. de Saussure, 1792) is in honour of the French geologist, D. G. Dolomieu, who in 1791 noted that certain Tyrolese calcareous rocks and Italian marbles effervesce only slightly in contact with acid; this name was for many years applied to the rock only, but was later extended to the crystallized mineral, first in the form dolomite-spar.

In the white crystalline dolomite-rock of the Binnenthal near Brieg in Switzerland beautiful water-clear crystals of dolomite are found; and crystallized masses occur embedded in serpentine, talc-schist and other magnesian silicate rocks. The best crystallized specimens are, however, usually found in metalliferous deposits; for example, in the iron mines of Traversella near Ivrea in Piedmont (as large twinned rhombohedra) and Cleator Moor in Cumberland; in the deposits of lead and zinc ores at Alston in Cumberland, Laxey in the Isle of Man, Joplin in Missouri; and in the silver veins of Schemnitz in Hungary and Guanajuato in Mexico.

Several varieties of dolomite have been distinguished, depending on differences in structure and chemical composition. Miemite is a crystallized or columnar variety, of a pale asparagus-green colour, from Miemo near Volterra in Tuscany; taraspite is a similar variety from Tarasp in Switzerland. Gurhofite, from Gurhof near Aggsbach in Lower Austria, is snow-white, compact and porcellanous. Brossite, from the Brosso valley near Ivrea in Piedmont, and tharandite, from Tharand in Saxony, are crystallized varieties containing iron. Closely related is the species ankerite (q.v.).

(L. J. S.)

Dolomite Rock.—The rock dolomite, also known as dolomitic or magnesian limestone, consists principally of the mineral of the same name, but often contains admixture of other substances, such as calcite, quartz, carbonate and oxides of iron, argillaceous material, and chert or chalcedony. Dolomites when very pure and well crystallized may be snowy white (e.g.some examples from the eastern Alps), but are commonly yellow, creamy, brownish or grey from the presence of impurities. They tend to be crystalline, though on a fine scale, and appear under the microscope composed of small sharply angular rhombohedra, with a perfect cleavage and very strong double refraction. They can be often recognized by this, but are most certainly distinguished from similar limestones or marbles by tests with weak acid. Dolomite dissolves only very slowly in dilute hydrochloric acid in the cold, but readily when the acid is warmed; limestones are freely attacked by the acid in either state. Magnesian limestones, which contain both dolomite and calcite, may be etched by exposing polished surfaces for a brief time to cold weak acid; the calcite is removed, leaving small pits or depressions. The distribution of the calcite may be rendered more clear by using ferric chloride solution. This is decomposed, leaving a yellow stain of ferric hydrate where the calcite occurred. Alternatively, a solution of aluminium chloride will serve; this precipitates gelantinous alumina on contact with calcite and the film can be stained with aniline dyes (Lemberg’s solution). The dolomite is not affected by these processes.

Dolomites of compact structure have a higher specific gravity than limestones, but they very often have a cavernous or drusy character, the walls of the hollows being lined with small crystals of dolomite with a pearly lustre and rounded faces. They are also slightly harder, and for these and other reasons they last better as building stones and wear better when used for paving or road-mending. Dolomites are rarely fossiliferous, as the process of dolomitization tends to destroy any organic remains originally present. As compared with limestones they are less frequently well bedded, but there are exceptions to this rule. Manydolomites, particularly those of the north of England, show a very remarkable concretionary structure. The beds look as if made up of rounded balls of all sizes from a foot or two in diameter downwards. Often they are stuck together like piles of shot or bunches of grapes. They are composed of fibrous radiate calcite crystals, which by some kind of concretionary action have segregated from the dolomitic material and grouped themselves together in this way. Other concretions from these beds resemble bunches of corals, tufts of plants, or present various strange imitative forms.

Dolomite, unlike calcite, is not secreted by marine animals to build up the hard parts of their skeletons, and it is generally agreed also that dolomite is only very rarely and under exceptional conditions deposited directly from solution in water. On the other hand, there is much evidence to show that limestones may absorb or be partly replaced by magnesium carbonate, and the double salt dolomite substituted for calcite by one of those processes which are described as “metasomatic.” Thus the Carboniferous limestones of various parts of Britain pass into dolomites along lines of joint, fissure or fault, or occasionally along certain bedding planes. At the same time the rock becomes crystalline, its minute structure is altered, its fossils are effaced, and as dolomite has a higher specific gravity than limestone, contraction results and cavities are formed. The prevalence of crystalline, concretionary and drusy structures in dolomite can thus be simply explained. The process may actually be studied in many “magnesian limestones,” in which by means of the microscope we may trace the gradual growth of dolomite crystals taking place simultaneously with the destruction of the original features of the limestone. Recent investigations in coral reefs show that these changes are going on at the present day at no considerable depths and in rocks which have not long consolidated.

All this goes to prove that the double carbonate of calcium and magnesium is under certain conditions a more stable salt than either of the simple carbonates, and that these conditions recur in nature with considerable frequency. Experiments have proved that at moderately high temperatures (100° to 200° C.) solutions of magnesium salts will convert calcite into dolomite in the laboratory, and that aragonite is even more readily affected than calcite. The analogy with dolomitization of limestones is strong but not complete, as the latter process must take place at ordinary temperatures and approximately under atmospheric pressures. No completely satisfactory explanation of the change, from the standpoint of the geologist, has as yet been advanced, though much light has been thrown upon the problem. Many limestones are rich in aragonite, but this in course of time tends to recrystallize as calcite. Magnesium salts are abundant in sea-water, and in the waters of evaporating enclosed coral lagoons and of many bitter lakes. Calcite is more soluble than dolomite in water saturated with carbonic acid and would tend to be slowly removed from a limestone, while the dolomite increased in relative proportion. Dolomite also being denser than calcite may be supposed to replace it more readily when pressure is increased. These and many other factors probably co-operate to effect the transmutation of limestones into dolomites.

Examples of dolomitization may be obtained in practically every geological formation in which limestones occur. The oldest rocks are most generally affected,e.g.the Cambrian limestones of Scotland, but the change occurs, as has already been stated, even in the upraised coral reefs of the Indian and Pacific oceans which are very recent formations. It is very interesting to note that dolomites are very frequent among rocks which indicate that desert or salt-lake conditions prevailed at the time of their deposit. The dolomite or magnesian limestone of the English Permian is an instance of this. The explanation may be found in the fact that the waters of bitter lakes are usually rich in magnesium salts which, percolating through beds of limestone, would convert them into dolomite. Among the most famous dolomites are those of the Dolomite Alps of Tirol. They are of Triassic age and yield remarkably picturesque mountain scenery; it is believed that some were originally coral reefs; they are now highly crystalline and often contain interesting minerals and ores. The galena limestone of the North American Trenton rocks is mostly a dolomite.

Dolomites furnish excellent building stones, and those of the north-east of England (Mansfield stone, &c.) have long been regarded with great favour on account of their resistance to decomposition. They vary a good deal in quality, and have not all proved equally satisfactory in practice. Part of the Houses of Parliament at Westminster is built of dolomite.

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