Chloride of barium possesses acrid-narcotic pro- overspreading the whole of the inside, and then a perties, its taste being irritating and burning. It layer of woody matter, which answers to the resembles medicinally chloride of calcium, but is spaces of wood included between the medullary more potent; in poisonous doses its action is si- processes. These annual additions, which are milar to arsenic, with this difference, that it requires called the liber, or endophloum (whence books, a larger dose to destroy life, and while its local which were written upon such layers properly action is less marked, producing less disintegration prepared, were called libri), must therefore be of the stomach, it is more rapidly absorbed and exactly the same in number as the annual layers produces death more speedily. It is rarely em- of wood, and would be arranged with equal ployed as a means of self-destruction, or of inten- regularity if the bark were not affected by any tional injury to others. Fortunately an efficient disturbing cause. But, in consequence of the antidote exists in agents readily procured, and in- wood's perpetual increase in diameter, there is an variably efficacious if speedily administered. Any incessant lateral strain upon the liber, so that alkaline sulphate, such as Epsom or Glauber salts, after the first year there is little trace of regularity or sulphuric acid greatly diluted, will instantly to be discovered in the structure of the bark. It form an insoluble and harmless sulphate of ba- soon becomes a mere confused mass of woody rytes. Medicinally this compound is employed tubes and cellular tissue, in which all trace of in very minute doses in various forms of scrofula. annual concentric formation has disappeared. The It possesses slight tonic powers, improves the ap- manner in which it was originally generated is petite, and promotes absorption, reducing the however said to be detected in some plants, by glandular enlargements. It once enjoyed, chiefly the facility with which the bark will peel into from the testimony of Hufeland, a high celebrity. layer after layer; but it may be doubted whether But, like many other muriates once confided in this phenomenon is not more connected with the for the removal of scrofula, it has almost fallen original arrangement of the ultimate vesicles of into disuse, particularly since iodine has become the bark than with the annual formations. These known. layers are sometimes so numerous, that as many as 150 have been separated on a single tree. When young, the bark is overspread with a BARJOLS. [VAR.] be pulled off, and which allows the green matter with which its cells are at that time filled to be seen through it; but this is soon ruptured by the expansion of the bark, and is never renewed. The green matter forms a cellular envelope called epiphloum, which, after exposure to the air, becomes brown, and loses its vitality; so that the bark of an exogenous tree consists, after a year or two, of living matter in the inside, and of dead BARK, in vegetable physiology, is the externa! coating of the stem and branches of plants, en-thin transparent skin, called cuticle, which may sheathing the wood. In woody Exogens it separates spontaneously from the wood in spring and summer, and in herbaceous plants of the same class it may be easily removed with a little care; but in Endogens and Acrogens it is so continuous with the central part of the stem, that it can never be divided except by violence, and by lacerating the tissue which lies immediately below it. This difference arises from the manner in which the plants of these three great natural classes re-matter on the outside. There is a perpetual spectively grow. Exogens add annually new tendency to throw the dead part off, which is matter to the inside of their bark and the outside evinced either by rending into perpendicular of their wood, which renders it necessary that a fissures, such as are seen upon old trunks, or by spontaneous separation of wood and bark should peeling away layer after layer, as in the birchtake place in order to make room for the newly tree, or by the rejection of irregular plates of ingenerated substance; but Endogens, which grow considerable size, as in the plane-tree. The cork by addition to their centre, and Acrogens, by of commerce is formed by the expansion of the elongation of their point, require no such separa-suberous layer, or mesophloum, and is the dead tion. In its anatomical structure bark consists of a mass of cellular tissue pierced longitudinally by woody matter, which is composed entirely of woody tubes without any trace of vessels, but which is sometimes accompanied by long fistular cavities, in which resinous, or milky, or juicy, or other secretions are lodged. part of the bark of the cork-tree, which is readily separated at the time when the living portion adheres firmly to the wood. That the bark of Exogens is thus continually perishing externally and renewing internally, is proved by a very simple experiment. Let a name be cut upon the bark of a rapidly growing tree; in a few years the letters will have disappeared. Or let a nail be driven into the bark; in time its head will be distinct from the substance in which it was originally buried, the upper part will next become visible, and in course of time the nail will be entirely thrown off. In the first year of its existence bark is a cylinder, the woody matter of which is a continuation of that of the wood itself. In Endogens and Acrogens it undergoes no material increase or alteration subsequently, unless it be that the parts are increased in quantity without shifting their In Endogens the only alteration which takes position. But in Exogens, in consequence of their place in the bark, from the period of its first forwood being annually augmented by external ad-mation, consists in its becoming more fibrous, and ditions, as before stated, the bark undergoes losing its green colour. In Acrogens it becomes annual changes. Corresponding with the annual simply harder. additions to the wood are annual additions to the The bark is always of considerable thickness in inside of the bark, consisting of a cellular layer proportion to the wood, especially in younger branches, and it contains a considerable quantity Independently of its chemical properties, bark of air in the cavities of its cells. These two cir- is of great occasional importance for its organic cumstances render it well adapted for one of its products. The woody tubes of the liber are often functions, namely, that of protecting its newly so tough as to be fit for cordage; and ropes have formed wood and its own liber from the effect of been manufactured from that of the willow, the changes in temperature. This is more amply lime, the cocoa-nut, the hibiscus tiliaceus, and provided for in trees of cold climates than in those many other plants. The liber of the lime-tree, of hot ones. For example, the bark of the Dou- the bread-fruit tree, and the paper mulberry, is glas fir, which bears the utmost inclemency of torn into slips and manufactured into useful mats; cold on the north-west coast of America, is ex- or, in the case of the two latter, is macerated and ceedingly thick; and in the birches, which beaten in water till it becomes thin enough to be are among the most hardy of northern trees, it is used as linen. A most elegant preparation of the the quantity of air which lies among the tissue liber is obtained from the lace-bark tree of Jathat gives to their bark the white appearance for maica, a kind of spurge-laurel (Daphne): in that which it is remarkable, and that, from its buoy- plant it is very white, separates freely into a ancy, renders it particularly well adapted for the great number of layers, and may be easily consides of canoes. verted into a substance very much resembling lace. This is effected simply by pulling the liber sideways, when its woody tubes separate into a net-work of lozenge-shaped meshes. [TIMBER.] Another supposed function of the bark is the carrying downwards those juices which have been elaborated in the leaves. There is, however, reason to question whether there is a descent of the sap of this kind. All the peculiar secretions of plants are undoubtedly formed in the cells in which they are found, and the notion of the descent of the sap has been founded on the fact of a general diffusion of the sap throughout every part of the plant. It sometimes happens that bark has another and a different function to perform, as in what are called succulent plants, which have no leaves except rudimentary organs, that perish almost as soon as they are generated: such are stapelias and cacti. In these subjects the bark undoubtedly performs the function of the leaves. BARK. Several kinds of bark, being used for processes in the arts or for medicines, enter largely into commerce. Of the former class are oak bark, cork bark, mimosa or wattle bark, and quercitron bark; and the most important among the latter is Jesuits' or Peruvian baik. [CINCHONA.] Some others, such as CINNAMON and CASSIA, are noticed elsewhere. Oak bark is extensively, and was formerly almost exclusively, used in tanning, for which it is valuable on account of the large proportion which it contains of the peculiar astringent called tannin. Sir H. Davy has shown that 8 lbs. of oak bark are equal in efficiency to 21 lbs. of galls, 3 lbs. of sumach, 7 lbs. of the bark of the Leicester willow, 11 lbs. of the bark of the Spanish chestnut, 18 lbs. of elm bark, or 21 lbs. of common willow bark. The quantity of tannin, however, varies both with the age of the trees, and with the season in which they are cut; being more abundant in the bark of young than of old trees, while if taken in the spring the bark has four and a half times the quantity, in a given weight, that it would have in the winter. For the mode of using oak bark, see TANNING. It is in bark that we find the essential principles of the oak, the larch, and other trees used by tanners; and of the cinnamon, the cinchona, and other aromatic or febrifugal species; and that we procure, by wounding it, such matters as resin and gum, which readily flow from incisions made in it. As all such secretions are formed in consequence of evaporation from the leaves, it would follow that the proper time for collecting them is at the period when the leaves have performed their office for the year, and all superfluity of moisture has been parted with this period is Cork bark, or Cork, is the outer bark of an winter, or the season of torpor. But, as at that evergreen oak (Quercus suber), which grows abuntime the liber adheres firmly to the wood, the dantly in Portugal, Spain, the south of France, spring is more frequently chosen for barking; and and Italy. Most of the cork bark used in Europe theory would say, that the proper time is just at is supplied by Spain and Portugal, but that of the the moment when the sap begins to be in motion, best quality by France. As the cork is really and the liber and sap to separate, and before the dead bark, it may be carefully removed without secretions have been diluted or dissolved by the injuring the tree, which may be stripped every ascent of fluid from the earth. But this will ob- eight or ten years, beginning when it is fifteen viously depend upon the nature of the substance years old. At each successive stripping the prowhich is sought for: for example, the greatest duce becomes greater, and better in quality. (See quantity of tannin is found in the youngest liber; Plate.) The inner bark, which contains much therefore, bark for tanners' purposes should be tannin, cannot be removed without destroying the stripped just before it begins to adhere to the tree. Cork bark is usually charred lightly when wood after the leaves are fully formed, and when taken from the tree, to improve the texture by they are in full action; because at that time the closing the pores; but this process, which is liable whole of the liber which is formed during the to impart a disagreeable flavour to liquors stopped year is developed, and few chemical changes have with cork so treated, is not required for the begun to take place in its constituent parts. Tur- thinner but closer layers of young bark. The pentine, again, will only flow in the summer; and lightness of cork recommends its use as floats for therefore that which is to be obtained by a spon- fishing-nets, for life-preservers, for insuring the taneous emission must be sought for at that season. buoyancy of life-boats, and for similar purposes; while its compressibility and elasticity, being com- which consists of a common thermometer introbined with closeness of pore, render it valuable for duced into the hollow end of a pole, and thus stopping bottles and casks. protected from being broken when thrust into The Greeks and Romans were both well ac- the tan. quainted with cork, and seem to have occasionally] BARK BEETLE, one of the insects named used it as stoppers for vessels, but it was not ex- Xylophagi, or wood-eaters. The name is given to tensively employed for this purpose till the seven-many of the family Coleoptera. One well known teenth century, when glass bottles-of which no form is the bark-chafer, or typographer beetle mention is made before the fifteenth century-(Tomicus typographus). began to be generally introduced. Cork trees BARKAL, JEBEL BARKAL, an isolated grow well in various parts of Algeria, and the sandstone-rock in Nubia, about a mile from the French government encourages their cultivation. right bank of the Nile, in 18° 31′ N. lat., and Mimosa, or Wattle bark, is collected from two 31° 46′ E. long. The rock rises abruptly on all species of Mimosa which abound in New South sides, and quite perpendicularly on the side toWales, Tasmania, and New Zealand, where it is wards the river, to the height of nearly 400 feet, employed in tanning. It contains about 150 lbs. forming a wide plateau at the summit. Its cirof pure tannin in a ton of bark, and it imparts a cumference at the base is about twenty-five reddish colour to the leather. minutes' walk. The remains of several great Quercitron bark is the produce of the Quercus temples lie between the mountain and the river. nigra or tinctoria, or North American oak, and is The most remarkable are that called the Typhoused as a yellow dye. The colouring matter resides nium, and the Great Temple. The Typhonium, wholly in the inner bark; and care is needful in the best preserved of all, was dedicated to Typhon, extracting it to avoid any admixture of the tann nor the evil genius, as appears from several figures of the bark, which would give a brown tinge. of Typhon still remaining. The temple is 108 feet in length; its entrance faces the S.S.E. The fore part of the temple is a regular construction; and the further or inner part is excavated in the rock itself. BARK, PERUVIAN. [CINCHONA.] BARK-BED, in Horticulture, is a bed formed of the spent bark used by tanners, placed in the inside of a brick pit in a glazed house, constructed for forcing, or for the growth of tender plants. Gar- The Great Temple, one of the largest monudeners use it for all plants which require what ments in Nubia, is at some distance from the they call bottom heat, that is to say, for all species rock; it was entirely a constructed edifice, but which are natives of tropical climates, and for the walls are now a heap of ruins, and the bases pine-apples especially. In constructing a bark- and fragments only of its seventy-eight pillars are bed, the coarsest bark which can be obtained after discernible. Two enormous propyla, each 65 the tanners have used it should be selected, because French feet long and nearly 40 feet in thickness, it is found that the slowness of the fermentation form the front of the temple; the entrance beand consequently the steadiness of the heat given tween them is 13 feet wide. The first or outer off, is in proportion to the size of the fragments of hall is 126 feet long and somewhat less in width; bark employed: small tan, broken into minute the lateral walls are 7 feet thick. The second pieces by machinery, although often the only ma- hall is 146 feet long and 85 feet wide. The third terial to be had, should consequently never be used chamber is 53 feet long and 41 feet wide, and if it can be avoided. After having been slightly it was separated by partition walls from two lateral dried by being spread in the sun, the tan is first chambers of smaller dimensions. A passage 13 laid in heaps, covered with mats, until fermenta- feet wide leads from this chamber into the next. tion has commenced; it is then transferred to the It is 36 feet square, and also stands between two brick pit, in which it is finally to remain. Having lateral chambers. At the farthest end, facing been lightly but evenly arranged in the pit, and the entrance, is an altar of grey granite, 4 feet the glass roof of the house having been closed, 9 inches square at the base; the sides are beautithe tan is left to undergo fermentation; which at fully sculptured. Behind the granite altar is a first is violent, evolving more heat than any plants narrow opening which leads into various small could bear. But in a few days it subsides; and chambers, communicating with each other. These when the temperature of the bed has fallen to formed the farthest extremity of the building, the 96° it is in a proper state to receive the pots, whole length of which is nearly 500 feet, accordwhich are to be plunged in it. The heat willing to Rüppel, in a line S.E. by S. and N.W. by gradually, but very slowly diminish to 60°, below N., the front being to the S.E. which it is scarcely desirable, in the opinion of Before the northern entrance of a ruined buildgardeners, that the tan should be retained; but ing, two lions of red granite were found. They the temperature may a second time be raised to are about seven feet in length. These two lions 70° or 80°, by turning the tan over, or fermenta- were brought from Barkal by Lord Prudhoe, in tion may be further renewed by the addition of a 1832, and were placed in the British Museum. small quantity of yeast. The temperature of the The material is a flesh-coloured granite; and tan is generally judged of by feeling the end of a the execution possesses a high degree of merit. stick which is thrust into the centre of the bed; Both of the lions are represented in a reclining but, as it is impossible to use so rude a test as posture, one lying on his right side and the other this with any accuracy, it is now more customary to on the left. employ what is called a Breegazzi's thermometer, At a quarter of an hour's distance from Mount BARKING. [ESSEX.] Barkal, and both to the N.W. and S.W. of it, are l'restorations' three beautiful churches in the distwo groups of small pyramids, many of them in trict of Wensleydale. His death happened at Leeds, good preservation. The largest of those which April 10, 1855. are entire is about 40 feet high. Several of them have small exterior temples attached to one side, BARLAAM. This person would le of very with an outer door and an inner one walled up, little consequence, but for the fact that he is leading apparently to the interior of the pyramid. nearly the last of those who wrote in Greek on The first European traveller who visited the ruins mathematics, and that his work is a curious illusof Barkal was Mr. Waddington; he was followed tration of the arithmetic which preceded the inby Cailliaud in 1821; and Cailliaud was followed troduction of algebra and the Indian notation. by Dr. Rüppel in 1824-25, who has given a very Bernard of Seminara in Calabria was born about minute description of them. the end of the 13th century. He took the vows BARKER, EDMUND HENRY, was born on as a member of the order of St. Basil at an early 22nd December, 1788, at his father's vicarage of age, and the name of Barlaam at the same time. Hollym, in Yorkshire. He entered in 1807 as He died probably about 1348. The mathematical work of Barlaam consists a student of Trinity College, Cambridge, but he did not take a degree, having (it is said) scrupled entirely of arithmetic and arithmetical geometry, to subscribe the bachelor's oath. Upon leaving then called Logistic. It was written in Greek, in the university he became amanuensis to Dr. Parr, six books. The first book is on the addition and in whose house at Hatton he resided for several subtraction of fractions; the second on their years. He then married and settled at Thetford, multiplication and division; the third on the in Norfolk. The last few years of his life were marked by painful reverses of fortune. They were spent chiefly in London, where he died, after a very short illness, on the 21st of March, 1839. · Barlaam is said to have written a work on multiplication and division of sexagesimals; the fourth on operations with surfaces and lines by means of numbers; the fifth on ratios, the sixth on numerical data. Delambre has reviewed the third book (Hist. d'Astrom. Anc.,' v. i. p. Mr. Barker's labours as a writer and editor 320). It altogether gives us but a poor idea of were very great. He was a constant contributor the science of the age, and justifies Delambre's to Valpy's Classical Journal.' He edited, with remark, that Barlaam must have had more leisure than ingenuity. English notes, for the use of schools, portions of several of the classics, both Greek and Latin; among which were Caesar, Tacitus, and Cicero, Xenophon and Demosthenes. He superintended the English impression of Anthon's edition of Lemprière's Classical Dictionary,' and of Noah Webster's English Dictionary.' He also joined with Professor Dunbar in the compilation of a Greek and English Lexicon. Mr. Barker was also, as is universally understood, the real efficient editor of Valpy's reprint of Henry Stephens's Thesaurus Lingus Græcæ,' London, 1816-1828, 10 vols. folio. right-angled triangles; and there is in the catalogue of De Thou's library the title of a work of his as follows: Arithmetica Demonstratio eorum qua Euclides Libro II. in Lineis demonstravit.' (No date or place.) BARLE US, or CASPAR VAN BAERLE, was born at Antwerp, in 1584, studied theology made professor of logic in the University of Leyden. at Leyden, and took orders. In 1617 he was Having taken the part of the Arminians against the Gomarists, he was dismissed from his situation in 1619. He then applied to the study of BARKER, THOMAS, often called Barker of medicine, in which he received his doctor's degree Bath, was born in that city in 1769, and died at Caen in Normandy. In 1631 he was made in 1847. He began his career by very attentively professor of philosophy and eloquence in the copying the Flemish and Dutch masters, especially newly established University of Amsterdam. He Rembrandt and Ruysdael; and having acquired died at Amsterdam in 1648. He wrote numerous sufficient proficiency, he executed several pictures works, chiefly in Latin; several poems, 2 vols. of familiar character, amongst which are noted 8vo., Amsterdam, 1645; an interesting history of those of the Woodman,' and of 'Old Tom.' Brazil, under the administration of Maurice, He also painted a large fresco in his house near count of Nassau, with the following title, 'Rerum Bath. per Octennium in Brasilia et alibi nuper gestaBARKER, WILLIAM GIDEON MICHAEL rum sub Præfectura J. Mauritii Nassovia CoJONES, better known as 'the Wensleydale poet,' mitis, Historia,' fol., Amsterdam, 1647. Brazil was the only son of Thomas and Sarah Barker of was then possessed partly by the Dutch, and East Wilton, Yorkshire, and was adopted and edu- partly by the Portuguese. Among his Latin cated by the late Rev. W. Jones, vicar of that parish. poems is Britannia Triumphans, which was His first publication was a copy of verses of consi- written on the accession of Charles I. to the derable promise, Stanzas on Cape Coast Castle.' throne. Barlæus's Dutch poems are written in He subsequently produced some other small and an easy and pure style, and contain many fine casual works; but that which made his name most conceptions. His 'Epistolæ' were published after widely known in the North of England was his his death, 2 vols. 8vo., Amsterdam, 1667. 'Three Days, or Histories and Antiquities of BARLE'RIA, a genus of plants belonging to Wensleydale,' published in 1854. He was an the natural order Acanthacea. The species are active member of the Archæological Institute, and natives of various parts of the East Indies: a few was mainly instrumental in saving from modern of them have been introduced into our gardens, of which Barleria lupulina, with its large bracts middle of the ear, alternately on each side, and ter, and where the sun is powerful immediately after the melting of the snow in spring, as is the case in parts of Russia, Poland, and some parts of North America. In most climates, where the winter consists of alternate frost and thaws, and the early part of spring is usually wet, as is the case in England, Scotland, and Ireland, the young barley is too apt to suffer from these vicissitudes, and the spring-sown barley gives the more certain prospect of a good crop: but the grain of the lat ter is seldom so heavy as that which has stood the winter, and, being harvested later, it interferes with the wheat harvest, which is an incon BARLEY (Hordeum), a grain too generally The winter-sown barley is generally of the six- Agricultural writers in general have distinguished the different species of barley, either from the time of sowing them, into winter barley and spring barley; or, from the number of rows of grains in the ears, into six-rowed, four-rowed, and two-rowed, or flat barley. Another distinction may be made between those which have the corolla strongly adhering to the seed, and those in which it separates from it, leaving the seed naked; from which circumstance these are called naked barleys. Without entering into any discussion whether these differences are sufficient to constitute distinct species, or are to be considered as varieties produced by climate, soil, or cultivation, we shall only observe that those kinds which are hardier, and will bear the winters of our climate, may also with success be sown in spring, as is the case with the Scotch bere or bigg. There seem, in fact, to be only two very distinct species of barley generally cultivated one which produces three perfect flowers, and as many seeds united at the base, at each joint of the rachis, or for its succulent stems and leaves, which make it by far the best sort to sow for the purpose of green food, for cattle and sheep; and, if fed off early, the roots will, in a rich soil, shoot out an abundance of fresh stems, and produce a good crop of grain at harvest. The barley most commonly cultivated in England is that which has only two rows. It is almost universally sown in spring. The varieties produced by difference of soil and cultivation, as well as by seed occasionally brought from other countries, are innumerable; they have been divided by most agricultural writers into the early ripe sorts and the late ripe, from the period of their being fit to reap. But this is a distinction which is not very accurate. It is well known that hot gravelly soils bring any grain to perfection in less time than the stronger and colder soils, and that the produce acquires from the soil in which it grew a disposition to ripen earlier or later. This property it retains for a few seasons, by some modification of its vegetating power, to which, for want of a better name, that of habit may be given, being analogous to the alterations produced on living animals by habit. Thus seed sown repeatedly in a light dry soil becomes early ripe, and that sown on heavy moist land late ripe, |