"Formosum pastor Corydon ardebat Alexin."
"Formosum pastor Corydon ardebat Alexin."
"Formosum pastor Corydon ardebat Alexin."
This poem of Barnfield's was the most extraordinary specimen hitherto produced in England of the licence introduced from Italy at the Renaissance. Although the poem was successful, it did not pass without censure from the moral point of view. Into the conventional outlines ofThe Affectionate Shepherdthe young poet has poured all his fancy, all his epithets, and all his coloured touches of nature. If we are not repelled by the absurd subject, we have to admit that none of the immediate imitators ofVenus and Adonishas equalled the juvenile Barnfield in the picturesqueness of his "fine ruff-footed doves," his "speckled flower call'd sops-in-wine," or his desire "by the bright glimmering of the starry light, to catch the long-bill'd woodcock." Two months later, in January 1595, Barnfield published his second volume,Cynthia, with certain Sonnets, and this time signed the preface, which was dedicated, in terms which imply close personal relations, to William Stanley, the new earl of Derby. This is a book of extreme interest; it exemplifies the earliest study both of Spenser and Shakespeare. "Cynthia" itself, a panegyric on Queen Elizabeth, is written in the Spenserian stanza, of which it is probably the earliest example extant outsideThe Faerie Queene. This is followed by a sequence of twenty sonnets, which have the extraordinary interest that, while preceding the publication of Shakespeare's sonnets by fourteen years, they are closer to them in manner than are any others of the Elizabethan age. They celebrate, with extravagant ardour, the charms of a young man whose initials seem to have been J. U. or J. V., and of whom nothing else seems known. These sonnets, which preceded even theAmorettiof Spenser, are of unusual merit as poetry, and would rank as high in quality as in date of publication if their subject-matter were not so preposterous. They show the influence of Drayton'sIdea, which had appeared a few months before; in that collection also, it is to be observed, there had appeared amatory sonnets addressed to a young man. If editors would courageously alter the gender of the pronouns, several of Barnfield's glowing sonnets might take their place at once in our anthologies. Before the publication of his volume, however, he had repented of his heresies, and had become enamoured of a "lass" named Eliza (or Elizabeth), whom he celebrates with effusion in an "Ode." This is probably the lady whom he presently married, and as we find him a grandfather in 1626 it is unlikely that the wedding was long delayed. In 1598 Barnfield published his third volume,The Encomion of Lady Pecunia, a poem in praise of money, followed by a sort of continuation, in the same six-line stanza, called "The Complaint of Poetry for the Death of Liberality." In this volume there is already a decline in poetic quality. But an appendix of "Poems in diverse Humours" to this volume of 1598 presents some very interesting features. Here appears what seems to be the absolutely earliest praise of Shakespeare in a piece entitled "A Remembrance of some English Poets," in which the still unrecognized author ofVenus and Adonisis celebrated by the side of Spenser, Daniel and Drayton. Here also are the sonnet, "If Music and sweet Poetry agree," and the beautiful ode beginning "As it fell upon a day," which were until recently attributed to Shakespeare himself. In the next year, 1599,The Passionate Pilgrimwas published, with the words "By W. Shakespeare" on the title-page. It was long supposed that this attribution was correct, but Barnfield claimed one of the two pieces just mentioned, not only in 1598, but again in 1605. It is certain that both are his, and possibly other things inThe Passionate Pilgrimalso; Shakespeare's share in the twenty poems of that miscellany being doubtless confined to the five short pieces which have been definitely identified as his. In the opinion of the present writer the sonnet beginning "Sweet Cytherea" has unmistakably the stamp of Barnfield, and is probably a gloss on the first rapturous perusal ofVenus and Adonis; the same is to be said of "Scarce had the sun," which isaut Barnfield, aut diabolus. One or two other contributions toThe Passionate Pilgrimmay be conjectured, with less confidence, to be Barnfield's. It has been stated that the poet was now studying the law at Gray's Inn, but for this the writer is unable to discover the authority, except that several members of that society are mentioned in the course of the volume of 1598. In all probability Barnfield now married and withdrew to his estate of Dorlestone (or Darlaston), in the county of Stafford, a house romantically situated on the river Trent, where he henceforth resided as a country gentleman. In 1605 he reprinted hisLady Pecunia, and this was his latest appearance as a man of letters. His son Robert Barnfield and his cousin Elinor Skrymsher were his executors when his will was proved at Lichfield; his wife, therefore, doubtless predeceased him. Barnfield died at Dorlestone Hall, and was buried in the neighbouring parish church of St Michael's, Stone, on the 6th of March 1627. The labours of Dr Grosart and of Professor Arber have thrown much light on the circumstances of Barnfield's career. He has taken of late years a far more prominent place than ever before in the history of English literature. This is due partly to the remarkable merit of his graceful, melodious and highly-coloured verse, which was practically unknown until it was privately printed in 1876 (ed. Grosart, Roxburghe Club), and at length given to the public in 1882 (ed. Arber,English Scholars' Library). It is also due to the mysterious personal relation of Barnfield to Shakespeare, a relation not easy to prove in detail, as it is built up on a great variety of small indications. It is, however, obvious that Barnfield warmly admired Shakespeare, whose earliest imitator he may be said to have been, and that between 1595 and 1600 the younger poet was so close to the elder that the compositions of the former could be confused with those of the latter. Barnfield died, as a poet, in his twenty-fifth year. Up to that time he had displayed a talent which, if he had pursued it, might have placed him very high among the English poets. As it is, he will always interest a certain number of readers as being, in his languid "Italianate" way, a sort of ineffectual Meleager in the rich Elizabethan anthology.
Besides the editions already cited,The Affectionate Shepherdwas edited by Mr J. O. Halliwell-Phillipps for the Percy Society (Early English Poetry, vol. xx.);The Encomion of Pecuniaand some other poems by J. Boswell (Roxburghe Club, 1816); and by J. P. Collier inIllustrations of Old English Literature(vol. i., 1866).
(E. G.)
BARNIM,the name of a district between the Spree, the Oder and the Havel, which was added to the mark of Brandenburg during the 13th century. In the 15th century it was divided into upper and lower Barnim, and these names are now borne by two circles (Kreise) in the kingdom of Prussia.
BARNIM,the name of thirteen dukes who ruled over various divisions of the duchy of Pomerania. The following are the most important:—
BarnimI. (c.1209-1278), called theGood, was the son of Bogislaus II., duke of Pomerania-Stettin, and succeeded to this duchy on his father's death in 1220. After he became of age he was engaged in a long struggle with external enemies, and in 1250 was compelled to recognize the supremacy of the margrave of Brandenburg. Having in 1264 united the whole of Pomerania under his rule, Barnim devoted his energies to improving its internal condition. He introduced German settlers and customs into the duchy, founded many towns, and was extremely generous towards ecclesiastical foundations. He died on the 13th or 14th of November 1278.
BarnimIII. (c.1303-1368), called theGreat, was the son of Otto I., duke of Pomerania-Stettin, and took a prominent part in the defence and government of the duchy before his father'sdeath in 1344. A long and intermittent struggle with the representatives of the emperor Louis IV., who had invested his own son Louis with the mark of Brandenburg, enabled him to gain military experience and distinction. A victory gained by him in August 1332 was mainly instrumental in freeing Pomerania for a time from the vexatious claim of Brandenburg to supremacy over the duchy, which moreover he extended by conquest. Barnim assisted the emperor Charles IV. in his struggle with the family of Wittelsbach. He died on the 24th of August 1368.
BarnimXI. (1501-1573), son of Bogislaus X., duke of Pomerania, became duke on his father's death in 1523. He ruled for a time in common with his elder brother George; and after George's death in 1531 he shared the duchy with his nephew Philip I., retaining for himself the duchy of Pomerania-Stettin. The earlier years of his rule were troubled by a quarrel with the margrave of Brandenburg, who wished to annex Pomerania. In 1529, however, a treaty was made which freed Pomerania from the supremacy of Brandenburg on condition that if the ducal family became extinct the duchy should revert to Brandenburg. Barnim adopted the doctrines of Martin Luther, and joined the league of Schmalkalden, but took no part in the subsequent war. But as this attitude left him without supporters he was obliged to submit to the emperor Charles V., to pay a heavy fine, and to accept theInterim, issued from Augsburg in May 1548. In 1569 Barnim handed over his duchy to his grand-nephew, John Frederick, and died at Stettin on the 2nd of June 1573.
BARNSLEY(Black, or properlyBleak Barnsley), a market town and municipal borough in the Barnsley parliamentary division of the West Riding of Yorkshire, England, 15 m. N. of Sheffield. Pop. (1891) 35,427; (1901) 41,086. It is served by the Midland, Great Central, Lancashire & Yorkshire, Great Northern, and Hull & Barnsley railways. It is in the parish of Silkstone, which gives name to important collieries. It is situated on rising ground west of the river Dearne, and, though it loses in attraction owing to its numerous factories, its neighbourhood has considerable natural beauty. Among the principal buildings and institutions are several churches, of which the oldest, the parish church of St Mary, was built in 1821 on an early site; court house, public hall, institute and free library. Among several educational institutions, the free grammar school dates from 1665; and a philosophical society was founded in 1828. A monument was erected in 1905 to prominent members of the Yorkshire Miners' Association. The park was presented in 1862 by the widow of Joseph Locke, M.P. The manufacture of iron and steel, and the weaving of linen and other cloth, are the two principal industries; but there are also bleachfields, printfields, dyeworks, sawmills, cornmills and malt-houses; and the manufacture of glass, needles and wire is carried on. There are large coalfields in the neighbourhood, which, indeed, extend under the town. Coal and coke are largely exported to London and Hull. In the vicinity, Monk Bretton Priory, a Cluniac foundation of 1157, retains a Perpendicular gatehouse, some Decorated domestic remains, and fragments of the church. Wentworth Castle, built in 1730 by Thomas, earl of Strafford, stands in a singularly beautiful park, and contains a fine collection of portraits of historical interest. Besides the communications afforded by railway, Barnsley has the advantage of connexion with the Aire and Calder Navigation system of canals. The borough is under a mayor, six aldermen and eighteen councillors. Area, 2385 acres.
At the time of the Domesday survey Ilbert de Lacy held Barnsley by gift of William the Conqueror as part of the honour of Pontefract, and the overlordship remained in his family until the reign of Stephen, when it was granted by Henry de Lacy to the monks of Pontefract. Henry III. in 1249 granted the prior and convent of Pontefract a market every Wednesday at Barnsley, and a fair on the vigil and feast of St Michael and two following days, and Henry VIII. in 1512 granted them a new fair on the day of the Conversion of St Paul and two following days. The monastery evidently also held another fair there called St Ellen's fair, for in 1583 Queen Elizabeth granted this fair and St Paul's fair and the market "lately belonging to the dissolved monastery of Pontefract" to one Henry Burdett, and Ralph and Henry his sons for their lives. Besides these charters and others granting land in Barnsley to the monks of Pontefract there is very little history of the town, since it was not until after the introduction of the linen manufacture in 1744 that it became really important. Before that time the chief industry had been wire-drawing, but this trade began to decrease about the end of the 18th century, just as the linen trade was becoming important. In 1869 Barnsley was incorporated.
See Rowland Jackson,The History of the Town and Township of Barnsley(1858);Victoria County History—Yorkshire.
BARNSTABLE,a seaport township and the county-seat of the county of the same name, in Massachusetts, U.S.A. Pop. (1900) 4364, of whom 391 were foreign-born; (1910, U.S. census) 4676. Barnstable is served by the New York, New Haven & Hartford Railway. It is situated between Cape Cod Bay on the N. and Nantucket Sound on the S., extending across Cape Cod. The soil of the township, unlike that of other parts of the county, is well adapted to agriculture, and the principal industry is the growing of vegetables and the supplying of milk and poultry for its several villages, nearly all of which are summer resorts. At Hyannis is a state normal school (1897; co-educational). Cranberries are raised in large quantities, and there are oyster and other shell fisheries. In the 17th century the mackerel and whale fisheries were the basis of economic life; the latter gave way later to the cod and other fisheries, but the fishing industry is now relatively unimportant. Much of the county is a region of sands, salt-marshes, beach-grass and scattered woods. From 1865 to 1895 the county diminished 20.1% in population. Barnstable was settled and incorporated in 1639 (county created 1685), and includes among its natives James Otis and Lemuel Shaw.
See F. Freeman,The History of Cape Cod: the Annals of Barnstable County(2 vols., Boston, 1858, 1862; and other impressions 1860 to 1869).
BARNSTAPLE,a seaport, market town and municipal borough, in the Barnstaple parliamentary division of Devonshire, England, on the river Taw, near the north coast. Pop. (1901) 14,137. It is served by the London & South-Western, the Great Western, and the Lynton & Barnstaple railways. The Taw is here crossed by a stone bridge of sixteen arches, said to have been built in the 12th or 13th century. The town manufactures lace, gloves, sail-cloth and fishing-nets, and has extensive potteries, tanneries, sawmills and foundries, while shipbuilding is also carried on. The harbour admits only small coasting vessels. The public buildings and institutions include a guildhall (1826), a free grammar school and a large market-place. The poet John Gay was born in the vicinity, and received his education at the grammar school, which at an earlier period had numbered Bishop Jewel among its pupils. It was founded in the 14th century, in connexion with a chantry. There are also some curious Jacobean almshouses. The borough is under a mayor, six aldermen and eighteen councillors. Area, 2236 acres.
Barnstaple (Berdestaple, Barnstapol, Barstaple, also Barum) ranks among the most ancient of royal boroughs. As early as Domesday, where it is several times mentioned, there were forty burgesses within the town and nine without, who rendered 40s. Tradition claims that King Athelstan threw up defensive earthworks here, but the existing castle is attributed to Joel of Totnes, who held the manor during the reign of William the Conqueror, and also founded a Cluniac priory, dedicated to St Mary Magdalene. From this date the borough and priory grew up side by side, but each preserving its independent privileges and rights of government until the dissolution of the latter in 1535. In Edward II.'s reign the burgesses petitioned for the restoration of rights bestowed by a pretended charter from Athelstan. The existence of this charter was denied, but the desired privileges were conceded, including the right to elect a mayor. The earliest authenticated charter is that of Henry I., which was confirmed in a charter of Henry II. The later charter states that the burgesses should have customs similar to those granted to London, and further charters confirmed the same right. A charter of Queen Mary in 1556 added some new privileges, and specified that the common council should consist of a mayor, two aldermenand twenty-four chief burgesses. James I., by a charter dated 1610, increased the number of chief burgesses to twenty-five and instituted a recorder, a clerk of the market, justices of the peace and other officers. This charter was confirmed in 1611 and 1689, and held force until the Municipal Corporations Act of 1835, which established six aldermen and eighteen councillors. The borough sent two members to parliament in 1295, and so continued to do until the Redistribution of Seats Act of 1885, when the representation was merged in that of the county. Barnstaple was once famous for its woollen trade, now entirely declined, and as early as the reign of Edward III. was an important naval port, with an extensive shipping trade. That this prosperity was not altogether uninterrupted is testified by the fact that, at the time of the Armada, the mayor pleaded inability to contribute three ships, on account of injuries to trade consequent on the war with Spain. The Friday market and the annual four days' fair in September are held by immemorial prescription.
See J. B. Gribble,Memorials of Barnstaple(Barnstaple, 1830).
BARNUM, PHINEAS TAYLOR(1810-1891), American showman, was born in Bethel, Connecticut, on the 5th of July 1810, his father being an inn- and store-keeper. Barnum first started as a store-keeper, and was also concerned in the lottery mania then prevailing in the United States. After failing in business, he started in 1829 a weekly paper,The Herald of Freedom, in Danbury; after several libel suits and a prosecution which resulted in imprisonment, he moved to New York in 1834, and in 1835 began his career as a showman, with his purchase and exploitation of a coloured woman, Joyce Heth, reputed to have been the nurse of George Washington, and to be over a hundred and sixty years old. With this woman and a small company he made well-advertised and successful tours in America till 1839, though Joyce Heth died in 1836, when her age was proved to be not more than seventy. After a period of failure, he purchased Scudder's American Museum, New York, in 1841; to this he added considerably, and it became one of the most popular shows in the United States. He made a special hit by the exhibition, in 1842, of Charles Stratton, the celebrated "General Tom Thumb" (seeDwarf). In 1844 Barnum toured with the dwarf in England. A remarkable instance of his enterprise was the engagement of Jenny Lind to sing in America at $1000 a night for one hundred and fifty nights, all expenses being paid by theentrepreneur. The tour began in 1850. Barnum retired from the show business in 1855, but had to settle with his creditors in 1857, and began his old career again as showman and museum proprietor. In 1871 he established the "Greatest Show on Earth," a travelling amalgamation of circus, menagerie and museum of "freaks," &c. This show, incorporated in the name of "Barnum, Bailey & Hutchinson," and later as "Barnum & Bailey's" toured all over the world. In 1907 the business was sold to Ringling Brothers. Barnum wrote several books, such asThe Humbugs of the World(1865),Struggles and Triumphs(1869), and hisAutobiography(1854, and later editions). He died on the 7th of April 1891.
BAROCCHIO(orBarozzi),GIACOMO,calledDa Vignola(1507-1573), Italian architect, was born at Vignola in the Modenese territory on the 1st of October 1507. His early work was conducted at Bologna, Piacenza, Assisi and Perugia, until he was summoned to Rome as papal architect under Pope Julius III. In 1564 he succeeded Michelangelo as the architect of St Peter's, and executed various portions of that fabric, besides a variety of works in Rome. The designs for the Escorial were also supplied by him. He is the author of an excellent work on theFive Orders of Architecture(Rome, 1563), and another work onPractical Perspective(Rome, 1583). To his extensive acquirements and exquisite taste were superadded an amenity of manners and a noble generosity that won the affection and admiration of all who knew him. He died in Rome on the 7th of July 1573. He was an eminent upholder of the classic style at a period when the style known asbaroquewas corrupting the architecture of Italy. The termbaroqueowes its origin to the Spanish wordbarruecoorberrueco, an imperfectly round pearl, and is not derived from the architect Barocchio, whose name so much resembles it. Yet it is curious that it was much used to describe a debased form of architecture encouraged by the Jesuits whose church in Rome was built by Barocchio.
BAROCCI(orBaroccio),FEDERIGO(1528-1612), Italian painter, was born at Urbino, where the genius of Raphael inspired him. In his early youth he travelled to Rome, where he painted in fresco and was warmly commended by Michelangelo. He then returned to Urbino, where, with the exception of some short visits to Rome, he continued to reside till his death. He acquired great fame by his paintings of religious subjects, in the style of which he to some extent imitated Correggio. His own followers were very numerous, but according to Lanzi (Hist. of Painting) carried their master's peculiarities to excess. Barocci also etched from his own designs a few prints, which are highly finished, and executed with great softness and delicacy.
BARODA,a native state of India, within the Gujarat province of Bombay, but in direct relations with the governor-general. It consists of four isolated divisions, each of which is interlaced in the most intricate fashion with British territory or with other native states. Three of these divisions—Kadi, Baroda and Nausari—are in Gujarat proper; the fourth, Amreli with Okhamandal, is in the peninsula of Kathiawar. The total area covers 8099 sq. m. In 1901 the population was 1,952,692, showing a decrease of 19% in the decade, compared with an increase of 11% in the preceding decade. This decrease was due partly to the famines of 1896-1897 and 1900-1901, partly to the epidemics of cholera and fever which accompanied them, and partly to the plague which attacked the state in as great measure as the surrounding presidency.
The princes of Baroda were one of the chief branches of the Mahratta confederacy, which in the 18th century spread devastation and terror over India. About 1721 one Pilaji gaekwar carved a fertile slice of territory out of Gujarat, and afterwards received the title of "Leader of the Royal Troops" from the peshwa. During the last thirty-two years of the century the house fell a prey to one of those bitter and unappeasable family feuds which are the ruin of great Indian families. In 1800 the inheritance descended to a prince feeble in body and almost idiotic in mind. British troops were sent in defence of the hereditary ruler against all claimants; a treaty was signed in 1802, by which his independence of the peshwa and his dependence on British government were secured. Three years later these and various other engagements were consolidated into a systematic plan for the administration of the Baroda territory, under a prince with a revenue of three-quarters of a million sterling, perfectly independent in all internal matters, but practically kept on his throne by subsidiary British troops. For some time the history of the gaekwars was very much the same as that of most territorial houses in India: an occasional able minister, more rarely an able prince; but, on the other hand, a long dreary list of incompetent heads, venal advisers and taskmasters oppressive to the people. At last a fierce family feud came to a climax. In 1873 an English committee of inquiry was appointed to investigate various complaints of oppression against the gaekwar, Malhar Rao, who had recently succeeded to the throne after being for a long time kept in prison by his brother, the former gaekwar. No real reform resulted, and in 1874 an attempt at poisoning the British resident led to the gaekwar being formally accused of the crime and tried by a mixed commission. The result of the trial (1875) was a failure to obtain a unanimous verdict on the charge of poisoning; the viceroy, Lord Northbrook, however, decided to depose Malhar Rao on the ground of gross misgovernment, the widow of his brother and predecessor, Khande Rao, being permitted to adopt an heir from among the descendants of the founder of the family. This heir, by name Sayaji Rao, then a boy of twelve years in the humble home of a Deccani cultivator, was educated by an English tutor, the administration being meanwhile placed for eight years under the charge of Sir T. Madhava Rao, formerly diwan of Travancore, one of the ablest and most enlightened of Indian statesmen. The result was a conspicuous success. The gaekwar showed himself a model prince, and his territoriesbecame as well governed and prosperous as a British district. He repeatedly visited Europe in company with his wife. In 1887 the queen-empress conferred upon him at Windsor the insignia of G.C.S.I., and in 1892 upon his wife the Imperial order of the crown of India.
The gross revenue of the state is more than a million sterling. In 1901 the state currency of Babashai rupees was withdrawn, and the British rupee was introduced. The regular military force consists of a field battery, with several regiments of cavalry and battalions of infantry. In addition, there is an irregular force of horse and foot. Compulsory education has been carried on experimentally since 1893 in the Amreli division with apparent success, the compulsory age being 7 to 12 for boys and 7 to 10 for girls. Special measures are also adopted for the education of low castes and aboriginal tribes. There is a female training college under a Christian lady superintendent. The Kala Bhavan, or technical school, has departments for drawing, carpentry, dyeing, weaving and agriculture. There is also a state museum under a European director, and a state library. Portions of the state are crossed by the Bombay & Baroda and the Rajputana railways. In addition, the state has constructed three railways of its own, on three different gauges. Other railways are in contemplation. The state possesses a cotton mill.
The city of Baroda is situated on the river Viswamitri, a station on the Bombay & Baroda railway, 245 m. N. of Bombay by rail. Pop. (1901) 103,790. The whole aspect of the city has been changed by the construction of handsome public buildings, the laying-out of parks and the widening of the streets. An excellent water-supply is provided from the Ajwa lake. The cantonments, garrisoned by a native infantry regiment, are under British jurisdiction, and have a population of 4000. The city contains a college and many schools. The chief hospitals are called after the countess of Dufferin, Sayaji Rao and Jamnabai, the widow of Khande Rao.
SeeBaroda Gazetteer, 1908.
BAROMETER(from Gr.βάρος, pressure, andμέτρον, measure), an instrument by which the weight or pressure of the atmosphere is measured. The ordinary or mercurial barometer consists of a tube about 36 in. long, hermetically closed at the upper end and containing mercury. In the "cistern barometer" the tube is placed with its open end in a basin of mercury, and the atmospheric pressure is measured by the difference of the heights of the mercury in the tube and the cistern. In the "siphon barometer" the cistern is dispensed with, the tube being bent round upon itself at its lower end; the reading is taken of the difference in the levels of the mercury in the two limbs. The "aneroid" barometer (from the Gr.α-privative, andνηρός, wet) employs no liquid, but depends upon the changes in volume experienced by an exhausted metallic chamber under varying pressures. "Baroscopes" simply indicate variations in the atmospheric pressure, without supplying quantitative data. "Barographs" are barometers which automatically record any variations in pressure.
Philosophers prior to Galileo had endeavoured to explain theHistorical.action of a suction pump by postulating a principle that "Nature abhorred a vacuum." When Galileo observed that a common suction pump could not raise water to a greater height than about 32 ft. he considered that the "abhorrence" was limited to 32 ft., and commended the matter to the attention of his pupil Evangelista Torricelli. Torricelli perceived a ready explanation of the observed phenomenon if only it could be proved that the atmosphere had weight, and the pressure which it exerted was equal to that of a 32-ft. column of water. He proved this to be the correct explanation by reasoning as follows:—If the atmosphere supports 32 feet of water, then it should also support a column of about 2½ ft. of mercury, for this liquid is about 13½ times heavier than water. This he proved in the following manner. He selected a glass tube about a quarter of an inch in diameter and 4 ft. long, and hermetically sealed one of its ends; he then filled it with mercury and, applying his finger to the open end, inverted it in a basin containing mercury. The mercury instantly sank to nearly 30 in. above the surface of the mercury in the basin, leaving in the top of the tube an apparent vacuum, which is now called theTorricellian vacuum; this experiment is sometimes known as theTorricellian experiment. Torricelli's views rapidly gained ground, notwithstanding the objections of certain philosophers. Valuable confirmation was afforded by the variation of the barometric column at different elevations. René Descartes and Blaise Pascal predicted a fall in the height when the barometer was carried to the top of a mountain, since, the pressure of the atmosphere being diminished, it necessarily followed that the column of mercury sustained by the atmosphere would be diminished also. This was experimentally observed by Pascal's brother-in-law, Florin Périer (1605-1672), who measured the height of the mercury column at various altitudes on the Puy de Dôme. Pascal himself tried the experiment at several towers in Paris,—Notre Dame, St Jacques de la Boucherie, &c. The results of his researches were embodied in his treatisesDe l'équilibre des liqueursandDe la pesanteur de la masse d'air, which were written before 1651, but were not published till 1663 after his death. Corroboration was also afforded by Marin Mersenne and Christiaan Huygens. It was not long before it was discovered that the height of the column varied at the same place, and that a rise or fall was accompanied by meteorological changes. The instrument thus came to be used as a means of predicting the weather, and it was frequently known as theweather-glass. The relation of the barometric pressure to the weather is mentioned by Robert Boyle, who expressed the opinion that it is exceedingly difficult to draw any correct conclusions. Edmund Halley, Leibnitz, Jean André Deluc (1727-1817) and many others investigated this subject, giving rules for predicting the weather and attempting explanations for the phenomena. Since the height of the barometric column varies with the elevation of the station at which it is observed, it follows that observations of the barometer afford a means for measuring altitudes. The early experiments of Pascal were developed by Edmund Halley, Edme Mariotte, J. Cassini, D. Bernoulli, and more especially by Deluc in hisRecherches sur les modifications de l'atmosphère(1772), which contains a full account of the early history of the barometer and its applications. More highly mathematical investigations have been given by Laplace, and also by Richard Ruhlmann (Barometrischen Hohenmessung., Leipzig, 1870). The modern aspects of the relation between atmospheric pressure and the weather and altitudes are treated in the articleMeteorology.
Many attempts have been made by which the variation in the height of the mercury column could be magnified, and so more exact measurements taken. It is not possible to enumerate in this article the many devices which have been proposed; and the reader is referred to Charles Hutton'sMathematical and Philosophical Dictionary(1815), William Ellis's paper on the history of the barometer in theQuarterly Journal of the Royal Meteorological Society, vol. xii. (1886), and E. Gerland and F. Traumüller'sGeschichte der physikalischen Experimentierkunst(1899). Descartes suggested a method which Huygens put into practice. The barometer tube was expanded into a cylindrical vessel at the top, and into this chamber a fine tube partly filled with water was inserted. A slight motion of the mercury occasioned a larger displacement of the water, and hence the changes in the barometric pressure were more readily detected and estimated. But the instrument failed as all water-barometers do, for the gases dissolved in the water coupled with its high vapour tension destroy its efficacy. The substitution of methyl salicylate for the water has been attended with success. Its low vapour tension (Sir William Ramsay and Sydney Young give no value below 70° C.), its low specific gravity (1.18 at 10° C.), its freedom from viscosity, have contributed to its successful use. In the form patented by C. O. Bartrum it is claimed that readings to .001 of an inch of mercury can be taken without the use of a vernier.
The diagonal barometer, in which the upper part of the tube is inclined to the lower part, was suggested by Bernardo Ramazzini (1633-1714), and also by Sir Samuel Morland (or Moreland). This form has many defects, and even when thetube is bent through 45° the readings are only increased in the ratio of 7 to 5. The wheel barometer of Dr R. Hooke, and the steel-yard barometer, endeavour to magnify the oscillation of the mercury column by means of a float resting on the surface of the mercury in the cistern; the motion of the float due to any alteration in the level of the mercury being rendered apparent by a change in the position of the wheel or steel-yard. The pendant barometer of G. Amontons, invented in 1695, consists of a funnel-shaped tube, which is hung vertically with the wide end downwards and closed in at the upper end. The tube contains mercury which adjusts itself in the tube so that the length of the column balances the atmospheric pressure. The instability of this instrument is obvious, for any jar would cause the mercury to leave the tube.
Fig. 1. Siphon Barometer.Fig.1. Siphon Barometer.
Fig.1. Siphon Barometer.
TheSiphon Barometer(fig. 1) consists of a tube bent in the form of a siphon, and is of the same diameter throughout. A graduated scale passes along the whole length of the tube, and the height of the barometer is ascertained by taking the difference of the readings of the upper and lower limbs respectively. This instrument may also be read by bringing the zero-point of the graduated scale to the level of the surface of the lower limb by means of a screw, and reading off the height at once from the surface of the upper limb. This barometer requires no correction for errors of capillarity or capacity. Since, however, impurities are contracted by the mercury in the lower limb, which is usually in open contact with the air, the satisfactory working of the instrument comes soon to be seriously interfered with.
Fig. 2. Cistern Barometer.Fig.2. Cistern Barometer.
Fig.2. Cistern Barometer.
Fig. 2 shows theCistern Barometerin its essential and simplest form. This barometer is subject to two kinds of error, the one arising from capillarity, and the other from changes in the level of the surface of the cistern as the mercury rises and falls in the tube, the latter being technically called theerror of capacity. If a glass tube of small bore be plunged into a vessel containing mercury, it will be observed that the level of the mercury in the tube is not in the line of that of the mercury in the vessel, but somewhat below it, and that the surface is convex. The capillary depression is inversely proportional to the diameter of the tube. In standard barometers, the tube is about an inch in diameter, and the error due to capillarity is less than .001 of an inch. Since capillarity depresses the height of the column, cistern barometers require an addition to be made to the observed height, in order to give the true pressure, the amount depending, of course, on the diameter of the tube.
The error of capacity arises in this way. The height of the barometer is the perpendicular distance between the surface of the mercury in the cistern and the upper surface of the mercurial column. Now, when the barometer falls from 30 to 29 inches, an inch of mercury must flow out of the tube and pass into the cistern, thus raising the cistern level; and, on the other hand, when the barometer rises, mercury must flow out of the cistern into the tube, thus lowering the level of the mercury in the cistern. Since the scales of barometers are usually engraved on their brass cases, which are fixed (and, consequently, the zero-point from which the scale is graduated is also fixed), it follows that, from the incessant changes in the level of the cistern, the readings would be sometimes too high and sometimes too low, if no provision were made against this source of error.
A simple way of correcting the error of capacity is—to ascertain (1) the neutral point of the instrument, or that height at which the zero of the scale is exactly at the height of the surface of the cistern, and (2) the rate of error as the barometer rises or falls above this point, and then apply a correction proportional toFortin's Barometer.this rate. The instrument in which the error of capacity is satisfactorily (indeed, entirely) got rid of isFortin's Barometer. Fig. 3 shows how this is effected. The upper part of the cistern is formed of a glass cylinder, through which the level of the mercury may be seen. The bottom is made like a bag, of flexible leather, against which a screw works. At the top of the interior of the cistern is a small piece of ivory, the point of which coincides with the zero of the scale. By means of the screw, which acts on the flexible cistern bottom, the level of the mercury can be raised or depressed so as to bring the ivory point exactly to the surface of the mercury in the cistern. In some barometers the cistern is fixed, and the ivory point is brought to the level of the mercury in the cistern by raising or depressing the scale.
Fig. 3. Fortin's Barometer.Fig.3.—Fortin's Barometer.
Fig.3.—Fortin's Barometer.
In constructing the best barometers three materials are employed, viz.:—(1) brass, for the case, on which the scale is engraved; (2) glass, for the tube containing the mercury; and (3) the mercury itself. It is evident that if the coefficient of expansion of mercury and brass were the same, the height of the mercury as indicated by the brass scale would be the true height of the mercurial column. But this is not the case, the coefficient of expansion for mercury being considerably greater than that for brass. The result is that if a barometer stand at 30 in. when the temperature of the whole instrument, mercury and brass, is 32°, it will no longer stand at 30 in. if the temperature be raised to 69°; in fact, it will then stand at 30.1 in.Corrections of the barometer reading.This increase in the height of the column by the tenth of an inch is not due to any increase of pressure, but altogether to the greater expansion of the mercury at the higher temperature, as compared with the expansion of the brass case with the engraved scale by which the height is measured. In order, therefore, to compare with each other with exactness barometric observations made at different temperatures, it is necessary to reduce them to the heights at which they would stand at some uniform temperature. The temperature to which such observations are reduced is 32° Fahr. or 0° cent.
If English units be used (Fahrenheit degrees and inches), this correction is given by the formula
in the centigrade-centimetre system the correction is .0001614 HT (H being the observed height and T the observed temperature). Devices have been invented which determine these corrections mechanically, and hence obviate the necessity of applying the above formula, or of referring to tables in which these corrections for any height of the column and any temperature are given.
The standard temperature of the English yard being 62° and not 32°, it will be found in working out the corrections from the above formula that the temperature of no correction is not 32° but 28.5°. If the scale be engraved on the glass tube, or if the instrument be furnished with a glass scale or with a wooden scale, different corrections are required. These may be worked out from the above formula by substituting for the coefficient of the expansion of brass that of glass, which is assumed to be 0.00000498, or that of wood, which is assumed to be 0. Wood, however, should not be used, its expansion with temperature being unsteady, as well as uncertain.
If the brass scale be attached to a wooden frame and be free to move up and down the frame, as is the case with many siphon barometers, the corrections for brass scales are to be used, since the zero-point of the scale is brought to the level of the lower limb; but if the brass scale befixedto a wooden frame, the corrections for brass scales are only applicable provided the zero of the scale be fixed at (or nearly at) the zero line of the column, and be free to expand upwards. In siphon barometers, with which an observation is made from two readings on the scale, thescale must be free to expand in one direction. Again, if only the upper part of the scale, say from 27 to 31 in., be screwed to a wooden frame, it is evident that not the corrections for brass scales, but those for wooden scales must be used. No account need be taken of the expansion of the glass tube containing the mercury, it being evident that no correction for this expansion is required in the case of any barometer the height of which is measured from the surface of the mercury in the cistern.
In fixing a barometer for observation, it is indispensable thatPosition of barometer.it be hung in a perpendicular position, seeing that it is theperpendicular distancebetween the surface of the mercury in the cistern and the top of the column which is the true height of the barometer. The surface of the mercury column is convex, and in noting the height of the barometer, it is not the chord of the curve, but its tangent which is taken. This is done by setting the straight lower edge of the vernier, an appendage with which the barometer is furnished, as a tangent to the curve. The vernier is made to slide up and down the scale, and by it the height of the barometer may be read true to 0.002 or even to 0.001 in.
It is essential that the barometer is at the temperature shown by the attached thermometer. No observation can be regarded as good if the thermometer indicates a temperature differing from that of the whole instrument by more than a degree. For every degree of temperature the attached thermometer differs from the barometer, the observation will be faulty to the extent of about 0.003 in., which in discussions of diurnal range, &c., is a serious amount.
Before being used, barometers should be thoroughly examined as to the state of the mercury, the size of cistern (so as to admit of low readings), and their agreement with some known standard instrument at different points of the scale. The pressure of the atmosphere is not expressed by the weight of the mercury sustained in the tube by it, but by the perpendicular height of the column. Thus, when the height of the column is 30 in., it is not said that the atmospheric pressure is 14.7 lb on the square inch, or the weight of the mercury filling a tube at that height whose transverse section equals a square inch, but that it is 30 in., meaning that the pressure will sustain a column of mercury of that height.
It is essential in gasometry to fix upon some standard pressure to which all measurements can be reduced. The height of the standard mercury column commonly used is 76 cms. (29.922 in.) of pure mercury at 0°; this is near the average height of the barometer. Since the actualforceexerted by the atmosphere varies with the intensity of gravity, and therefore with the position on the earth's surface, a place must be specified in defining the standard pressure. This may be avoided by expressing the force as the pressure in dynes due to a column of mercury, one square centimetre in section, which is supported by the atmosphere. If H cms. be the height at 0°, andgthe value of gravity, the pressure is 13.596 Hgdynes (13.596 being the density of mercury). At Greenwich, whereg= 981.17, the standard pressure at 0° is 1,013,800 dynes. At Paris the pressure is 1,013,600 dynes. The closeness of this unit to a mega-dyne (a million dynes) has led to the suggestion that a mega-dyne per square centimetre should be adopted as the standard pressure, and it has been adopted by some modern writers on account of its convenience of calculation and independence of locality.
The height of the barometer is expressed in English inchesBarometric readings.in England and America, but the metric system is used in all scientific work excepting in meteorology. In France and most European countries, the height is given in millimetres, a millimetre being the thousandth part of a metre, which equals 39.37079 English inches. Up to 1869 the barometer was given in half-lines in Russia, which, equalling the twentieth of an English inch, were readily reduced to English inches by dividing by 20. The metric barometric scale is now used in Russia. In a few European countries the French or Paris line, equalling 0.088814 in., is sometimes used. The English measure of length being a standard at 62° Fahr., the old French measure at 61.2°, and the metric scale at 32°, it is necessary, before comparing observations made with the three barometers, to reduce them to the same temperature, so as to neutralize the inequalities arising from the expansion of the scales by heat.
The sympiezometer was invented in 1818 by Adie of Edinburgh.Sympiezometer.It is a revived form of Hooke's marine barometer. It consists of a glass tube, with a small chamber at the top and an open cistern below. The upper part of the tube is filled with air, and the lower part and cistern with glycerin. When atmospheric pressure is increased, the air is compressed by the rising of the fluid; but when it is diminished the fluid falls, and the contained air expands. To correct for the error arising from the increased pressure of the contained air when its temperature varies, a thermometer and sliding-scale are added, so that the instrument may be adjusted to the temperature at each observation. It is a sensitive instrument, and well suited for rough purposes at sea and for travelling, but not for exact observation. It has long been superseded by theAneroid, which far exceeds it in handiness.