In the Lavoisierian nomenclature acids were regarded as binary oxygenated compounds, the associated water being relegated to the position of a mere solvent. Somewhat similar views were held by Berzelius, when developing his dualistic conception of the composition of substances. In later years Berzelius renounced the ``oxygen acid'' theory, but not before Davy, and, almost simultaneously, Dulong, had submitted that hydrogen and not oxygen was the acidifying principle. Opposition to the ``hydrogen-acid'' theory centred mainly about the hypothetical radicals which it postulated; moreover, the electrochemical theory of Berzelius exerted a stultifying influence on the correct views of Davy and Dulong. In Berzelius' system potassium sulphate is to be regarded as K2O+.SO3-; electrolysis should simply effect the disruption of the positive and negative components, potash passing with the current, and sulphuric acid against the current. Experiment showed, however, that instead of only potash appearing at the negative electrode, hydrogen is also liberated; this is inexplicable by Berzelius's theory, but readily explained by the ``hydrogen-acid'' theory. By this theory potassium is liberated at the negative electrode and combines immediately with water to form potash and hydrogen.
Further and stronger support was given when J. Liebig promoted his doctrine of polybasic acids. Dalton's idea that elements preferentially combined in equiatomic proportions had as an immediate inference that metallic oxides contained one atom of the metal to one atom of oxygen, and a simple expansion of this conception was that one atom of oxide combined with one atom of acid to form one atom of a neutral salt. This view, which was specially supported by Gay-Lussac and Leopold Gmelin and accepted by Berzelius, necessitated that all acids were monobasic. The untenability of this theory was proved by Thomas Graham's investigation of the phosphoric acids; for he then showed that the ortho- (ordinary), pyro- and metaphosphoric acids contained respectively 3, 2 and 1 molecules of ``basic water'' (which were replaceable by metallic oxides) and one molecule of phosphoric oxide, P2 O5. Graham's work was developed by Liebig, who called into service many organic acids—-citric, tartaric, cyanuric, comenic and meconic—-and showed that these resembled phosphoric acid; and he established as the criterion of polybasicity the existence of compound salts with different metallic oxides. In formulating these facts Liebig at first retained the dualistic conception of the structure of acids; but he shortly afterwards perceived that this view lacked generality since the halogen acids, which contained no oxygen but yet formed salts exactly similar in properties to those containing oxygen, could not be so regarded. This and other reasons led to his rejection of the dualistic hypothesis and the adoption, on the ground of probability, and much more from convenience, of the tenet that ``acids are particular compounds of hydrogen, in which the latter can be replaced by metals''; while, on the constitution of salts, he held that ``neutral salts are those compounds of the same class in which the hydrogen is replaced by its equivalent in metal. The substances which we at present term anhydrous acids (acid oxides) only become, for the most part, capable of forming salts with metallic oxides after the addition of water, or they are compounds which decompose these oxides at somewhat high temperatures.''
The hydrogen theory and the doctrine of polybasicity as enunciated by Liebig is the fundamental characteristic of the modern theory. A polybasic acid contains more than one atom of hydrogen which is replaceable by metals; moreover, in such an acid the replacement may be entire with the formation of normal salts, partial with the formation of acid salts, or by two or more different metals with the formation of compound salts (see SALTS). These facts may be illustrated with the aid of orthophosphoric acid, which is tribasic:— Acid. Normal salt. Acid salts. H3PO4 Ag3PO4 Na2HPO4; NaH2PO4 Phosphoric Silver phosphate. Acid sodium acid. phosphates. Compound salts. Mg(NH4)PO4; Na(NH4)HPO4. Magnesium ammonium Microcosmic phosphate; salt. Reference should be made to the articles CHEMICAL ACTION, THERMOCHEMISTRY and SOLUTIONS, for the theory of the strength or avidity of acids.
Organic Acids.—-Organic acids are characterized by the presence of the monovalent group—CO.OH, termed the carboxyl group, in which the hydrogen atom is replaceable by metals with the formation of salts, and by alkyl radicals with the formation of esters. The basicity of an organic acid, as above defined, is determined by the number of carboxyl groups present. Oxy-acids are carboxyllc acids which also contain a hydroxyl group; similarly we may have aldehyde-acids, ketone-acids, &c. Since the more important acids are treated under their own headings, or under substances closely allied to them, we shall here confine ourselves to general relations.
Classification.—It is convenient to distinguish between aliphatic and aromatic acids; the first named being derived from open-chain hydrocarbons, the second from ringed hydrocarbon nuclei. Aliphatic monobasic acids are further divided according to the nature of the parent hydrocarbon. Methane and its homologues give origin to the ``paraffin'' or ``fatty series'' of the general formula Cn H2n+1COOH, ethylene gives origin to the acrylic acid series, CnH2n-1COOH, and soon. Dibasic acids of the paraffin series of hydrocarbons have the general formula CnH2(COOH)2n; malonic and succinic acids are important members. The isomerism which occurs as soon as the molecule contains a few carbon atoms renders any classification based on empirical molecular formulae somewhat ineffective; on the other hand, a scheme based on molecular structure would involve more detail than it is here possible to give. For further information, the reader is referred to any standard work on organic chemistry. A list of the acids present in fats and oils is given in the article OILS.
Syntheses of Organic Acids.—-The simplest syntheses are undoubtedly those in which a carboxyl group is obtained directly from the oxides of carbon, carbon dioxide and carbon monoxide. The simplest of all include: (1) the synthesis of sodium oxalate by passing carbon dioxide over metallic sodium heated to 350 deg. -360 deg. ; (2) the synthesis of potassium formate from moist carbon dioxide and potassium, potassium carbonate being obtained simultaneously; (3) the synthesis of potassium acetate and propionate from carbon dioxide and sodium methide and sodium ethide; (4) the synthesis of aromatic acids by the interaction of carbon dioxide, sodium and a bromine substitution derivative; and (5) the synthesis of aromatic oxy-acids by the interaction of carbon dioxide and sodium phenolates (see SALICYLIC ACID). (Carbon monoxide takes part in the syntheses of sodium formate from sodium hydrate, or soda lime (at 200 deg. -220 deg. ), and of sodium acetate and propionate from sodium methylate and sodium ethylate at 160 deg. —200 deg. . Other reactions which introduce carboxyl groups into aromatic groups ave: the action of carbonyl chloride on aromatic hydrocarbons in the presence of aluminium chloride, acid-chlorides being formed which are readily decomposed by water to give the acid; the action of urea chloride Cl.CO.NH2, cyanuric acid (CONH)3, nascent cyanic acid, or carbanile on hydrocarbons in the presence of aluminium chloride, acid-amides being obtained which are readily decomposed to give the acid. An important nucleus-synthetic reaction is the saponification of nitriles, which may be obtained by the interaction of potassium cyanide with a halogen substitution derivative or a sulphonic acid.
Acids frequently result as oxidation products, being almost invariably formed in all cases of energetic oxidation. There are certain reactions, however, in which oxidation can be successfully applied to the synthesis of acids. Thus primary alcohols and aldehydes, both of the aliphatic and aromatic series, readily yield on oxidation acids containing the same number of carbon atoms. These reactions may be shown thus:- R.CH2OH -> R.CHO -> R.CO.OH. In the case of aromatic aldehydes, acids are also obtained by means of ``Cannizzaro's reaction'' (see BENZALDEHYDE). An important oxidation synthesis of aromatic acids is from hydrocarbons with aliphatic side chains; thus toluene, or methylbenzene, yields benzoic acid, the xylenes, or dimethyl-benzene, yield methyl-benzoic acids and phthalic acids. Ketones, secondary alcohols and tertiary alcohols yield a mixture of acids on oxidation. We may also notice the disruption of unsaturated acids at the double linkage into a mixture of two acids, when fused with potash.
In the preceding instances the carboxyl group has been synthesized or introduced into a molecule; we have now to consider syntheses from substances already containing carboxyl groups. Of foremost importance are the reactions termed the malonic acid and the aceto-acetic ester syntheses; these are discussed under their own headings. The electrosyntheses call for mention here. It is apparent that metallic salts of organic acids would, in aqueous solution, be ionized, the positive ion being the metal, and the negative ion the acid residue. Esters, however, are not ionized. It is therefore apparent that a mixed salt and ester, for example KO2C.CH2.CH2.CO2C2H5, would give only two ions, viz. potassium and the rest of the molecule. If a solution of potassium acetate be electrolysed the products are ethane, carbon dioxide, potash and hydrogen; in a similar manner, normal potassium succinate gives ethylene, carbon dioxide, potash and hydrogen; these reactions may be represented:- CH3.CO2 K CH3 CO2 K* CH2.CO K CH2 CO2 K. | -> | + + | | ->|| + + CH3.CO2 K CH3 CO2 K* CH2.CO K CH2 CO2 K. By electrolysing a solution of potassium ethyl succinate, KO2C.(CH2)2CO2C2H5, the KO2C. groups are split off and the two residues .(CH2)2CO2C2H5 combine to form the ester (CH2)4(CO2C2H5)2. In the same way, by electrolysing a mixture of a metallic salt and an ester, other nuclei may be condensed; thus potassium acetate and potassium ethyl succinate yield CH3.CH2.CH2.CO2C2H5.
Reactions.—Organic acids yield metallic salts with bases, and ethereal salts or esters (q.v.), R.CO.OR', with alcohols. Phosphorus chlorides give acid chlorides, R.CO.Cl, the hydroxyl group being replaced by chlorine, and acid anhydrides, (R.CO)2O, a molecule of water being split off between two carboxyl groups. The ammonium salts when heated lose one mobecule of water and are converted into acid-amides, R.CO.NH2, which by further dehydration yield nitriles, R.CN. The calcium salts distilled with calcium formate yield aldehydes (q.v.); distilled with soda-lime, ketones (q.v.) result.
ACIDALIUS, VALENS (1567-1595), German scholar and critic, was born at Wittstock in Brandenburg. After studying at Rostock, Grelfswald and Helmstedt, and residing about three years in Italy, he settled at Breslau, where he is said to have embraced the Roman Catholic religion. Early in 1595 he accepted an invitation to Neisse, about fifty miles from Breslau, where he died of brain fever on the 25th of May, at the age of twenty-eight. His excessive application to study, and the attacks made upon him in connexion with a pamphlet of which he was reputed the author, doubtless hastened his premature end. Acidalius wrote notes on Velleius Paterculus (1590), Curtius (1594), the panegyrists, Tacitus and Plautus, published after his death.
See Leuschner, Commeutatio de A. V. Vita, Moribus, et Scriptis (1757); F. Adam, ``Der Neisser Rektor,'' in Bericht der Philomathic in Neisse (1872).
ACID-AMIDES, chemical compounds which may be considered as derived from ammonia by replacement of its hydrogen with acidyl residues, the substances produced being known as primary, secondary or tertiary amides, according to the number of hydrogen atoms replaced. Of these compounds, the primary amides of the type R.CO.NH2 are the most important. They may be prepared by the dry distillation of the ammonium salts of the acids (A. W. Hofmann, Ber., 1882, 15, p. 977), by the partial hydrolysis of the nitriles, by the action of ammonia or ammonium carbonate on acid chlorides or anhydrides, or by heating the esters (q.v.) with ammonia. They are solid crystalline compounds (formamide excepted) which are at first soluble in water, the solubility, however, decreasing as the carbon content of the molecule increases. They are easily hydrolysed, breaking up into their components when boiled with acids or alkanes. They form compounds with hydrochloric acid when this gas is passed into their ethereal solution; these compounds, however, are very unstable, being readily decomposed by water. On the other hand, they show faintly acid properties since the hydrogen of the amide group can be replaced by metals to give such compounds as mercury acetamide (CH3CONH)2Hg. Nitrous acid decomposes them, with elimination of nitrogen and the formation of the corresponding acid, RCO.NH2 + ONOH = R.COOH + N2 + H2O. When distilled with phosphoric anhydride they yield nitriles. By the action of bromine and alcoholic potash on the amides, they are converted into amines containing one carbon atom less than the original amide, a reaction which possesses great theoretical importance (A. W. Hofmann), R.CONH2 -> R.CONHBr -> R.NH2 + K2CO3 + KBr + H2O. Formamide, H.CONH2, is a liquid readily soluble in water, boillng at about 195 deg. C. with partial decomposition. Acetamide, CH3.CONH2, is a white deliquescent crystalline solid, which melts at 82-83 deg. C. and boils at 222 deg. C. It is usually prepared by distilling ammonium acetate. It is readily soluble in water and alcohol, but insoluble in ether. Benzamide, C6H5.CONH2, crystallizes in leaflets which melt at 130 deg. C. It is prepared by the action of ammonium carbonate on benzoyl chloride. It yields a silver salt which with ethyl iodide forms benzimidoethyl ether, C6H5C: (NH).OC2H5, a behaviour which points to the silver salt as being derived from the tautomeric imidobenzoic acid, C6H5C: (NH).OH (J. Tafel, Ber., 1890, 23, p. 104). On the preparation of the substituted amides from the corresponding sodamides see A. W. Titherley (Journ. Chem. Soc., 1901, 59, p. 391). The secondary and tertiary amides of the types (RCO)2NH and (RCO)3N may be prepared by heating the primary amides or the nitriles with acids or acid anhydrides to 200 deg. C. Thiamides of the type R.CSNH2 are known, and result by the addition of sulphuretted hydrogen to the nitriles, or by the action of phosphorus pentasulphide on the acid-amides. They readily decompose on heating, and are easily hydrolysed by alkanes; they possess a somewhat more acid character than the acid-amides.
ACINACES (from the Greek), an ancient Persian sword, short and straight, and worn, contrary to the Roman fashion, on the right side, or sometimes in front of the body, as shown in the bas-reliefs found at Persepolis. Among the Persian nobility it was frequently made of gold, being worn as a badge of distinction. The acinaces was an object of religious worship with the Scythians and others (Herod. iv. 62).
ACINETA (so named by C. G. Ehrenberg), a genus of suctorialInfusoria characterized by the possession of a stalk andcup-shaped sheath or theca for the body, and endogenous budding.O. Butschli has separated off the genus Metacineta (forA. mystacina), which reproduces by direct bud-fission.
ACINUS (Lat. for a berry), a term in botany applied to such fruits as the blackberry or raspberry, composed of small seedlike berries, and also to those berries themselves, or to grapestones. By analogy, acinus is applied in anatomy to similar granules or glands, or lobules of a gland.
ACIREALE, a town and episcopal see of the province of Catania, Sicily; from the town of the same name it is distant 9 m. N. by E. Pop. (1901) 35,418. It has some importance as a thermal station, and the springs were used by the Romans. It takes its name from the river Acis, into which, according to the legend, Acis, the lover of Galatea, was changed after he had been slain by Polyphemus. The rocks which Polyphemus hurled at Ulysses are identified with the seven Scogli de' Ciclopi, or Faraglioni, a little to the south of Acireale.
ACIS, in Greek mythology, the son of Pan (Faunus) and the nymph Syntaethis, a beautiful shepherd of Sicily, was the lover of the Nereid Galatea. His rival the Cyclops Polyphemus surprised them together, and crushed him to pieces with a rock. His blood, gushing forth from beneath, was metamorphosed by Galatea into the river bearing his name (now Fiume di Jaci), which was celebrated for the coldness of its waters (Ovid, Met. xiii. 750; Silius Italicus, Punica, xiv. 221).
ACKERMAN, FRANCIS (c. 1335—1387), Flemish soldier and diplomatist, was born at Ghent, and about 1380 became prominent during the struggle between the burghers of that town and Louis II. (de Male), count of Flanders. He was partly responsible for inducing Philip van Artevelde to become first captain of the city of Ghent in 1382, and at the head of some troops scoured the surrounding country for provisions and thus saved Ghent from being starved into submission. By his diplomatic abilities he secured the assistance of the citizens of Brussels, Louvain and Liege, and, having been made admiral of the Flemish fleet, visited England and obtained a promise of help from King Richard II. After Artevelde's death in November 1382, he acted as leader of the Flemings, gained several victories and increased his fame by skilfully conducting a retreat from Damme to Ghent in August 1385. He took part in the conclusion of the treaty of peace between Ghent and Philip the Bold, duke of Burgundy, the successor of Count Louis, in December 1385. Trusting in Philip, and ignoring the warnings of his friends, Ackerman remained in Flanders, and was murdered at Ghent on the 22nd of July 1387, leaving a memory of chivalry and generosity.
See Jean Froissart, Chroniques, edited by S. Luce and G. Raynaud (Paris, 1869-1897); Johannes Brandon, Chronodromon, edited hy K. de Lettenhove in the Chroniques rotatives a L'histoire de La Belgique sous la domination des ducs de Bourgogne (Brussels, 1870).
ACKERMANN, JOHANN CHRISTIAN GOTTLIEB (1756-1801), German physician, was born at Zeillenroda, in Upper Saxony, on the 17th of February 1756, and died at Altdorf on the 9th of March 1801. At the age of fifteen he became a student of medicine at Jena under E. G. Baldinger, whom he followed to Gottingen in 1773, and afterwards he studied for two years at Halle. A few years' practice at Stendal (1778-1799), where there were numerous factories, enabled him to add many valuable original observations to his translation (1780-1783) of Bernardino Ramazzini's (1633-1714) treatise on diseases of artificers. In 1786 he became professor of medicine at the university of Altdorf, in Franconia, occupying first the chair of chemistry, and then, from 1794 till his death in 1801, that of pathology and therapeutics. He wrote Institutiones Historiae Medicinae (Nuremberg, 1792) and Institutiones Therapiae Generalls (Nuremberg and Altdorf, 1784-1795), besides various handbooks and translations.
ACKERMANN, LOUISE VICTORINE CHOQUET (1813-1890), French poet, was born in Paris on the 30th of November 1813. Educated by her father in the philosophy of the Encyclopaedists, Victorine Choquet went to Berlin in 1838 to study German, and there married in 1843 Paul Ackermann, an Alsatian philologist. After little more than two years of happy married life her husband died, and Madame Ackermann went to live at Nice with a favourite sister. In 1855 she published Contes en vers, and in 1862 Contes et poesies. Very different from these simple and charming contes is the work on which Madame Ackermann's real reputation rests. She published in 1874 Poesies, premieres poesies, poesies philosophiques, a volume of sombre and powerful verse, expressing her revolt against human suffering. The volume was enthusiastically reviewed in the Revue des deux mondes for May 1871 by E. Caro, who, though he deprecated the impiete desesperee of the verses, did full justice to their vigour and the excellence of their form. Soon after the publication of this volume Madame Ackermann removed to Paris,where she gathered round her a circle of friends, but published nothing further except a prose volume, the Pensees d'un solitaire (1883), to which she prefixed a short autobiography. She died at Nice on the 2nd of August 1890.
See also Anatole France, La vie litteraire, 4th series (1892);the comte d'Haussonville, Mme. Ackermann (1882); M. Citoleux,La poesie philosophique au XIXe. siecle (vol. i., Mme.Ackermann d'apres de nombreux documents inedits, Paris, 1906).
ACKERMANN, RUDOLPH (1764-1834), Anglo-German inventor and publisher, was born on the 20th of April 1764 at Schneeberg, in Saxony. He had been a saddler and coachbuilder in different German cities, Paris and London for ten years before, in 1795, he established a print-shop and drawing-school in the Strand. Ackermann set up a lithographic press, and applied it in 1817 to the illustration of his Repository of Arts, Literature, Fashions,; &c. (monthly until 1828 when forty volumes had appeared). Rowlandson and other distinguished artists were regular contributors. He also introduced the fashion of the once popular English Annuals, beginning in 1825 with Forget-me-not; and he published many illustrated volumes of topography and travel, The Microcosm of London (3 vols., 1808-1811), Westminster Abbey (2 vols., 1812), Pine Rhine (1820), The World in Miniature (43 vols., 1821—1826), &c. Ackermann was an enterprising man; he patented (1801) a method for rendering paper and cloth waterproof, erected a factory at Chelsea for the purpose and was one of the first to illuminate his own premises with gas. Indeed the introduction of lighting by gas owed much to him. After the battle of Leipzig Ackermann collected nearly a quarter of a million sterling for the German sufferers. He died at Finchley, near London, on the 30th of March 1834.
ACKNOWLEDGMENT (from the old acknow, a compound of on- and know, to know by the senses, which passed through the forms oknow, aknow and acknow; acknowledge is formed on analogy of ``knowledge''), an admission that something has been given or done, a term used in law in various connexions. The acknowledgment of a debt, if in writing signed by the debtor or his agent, is sufficient to take it out of the Statutes of Limitations. The signature to a will by a testator, if not made in the presence of two witnesses, may be afterwards acknowledged in their presence. The acknowledgment by a woman married before 1882 of deeds for the conveyance of real property not her separate property, requires to be made by her before a judge of the High Court or of a county court or before a perpetual or special commissioner. Before such an acknowledgment can be received, the judge or commissioner is required to examine her apart from her husband, touching her knowledge of the deed, and to ascertain whether she freely and voluntarily consents to it. An acknowledgment to the right of the production of deeds of conveyance is an obligation on the vendor, when he retains any portion of the property to which the deeds relate, and is entitled to retain the deeds, to produce them from time to time at the request of the person to whom the acknowledgment is given, to allow copies to be made, and to undertake for their safe custody (Conveyancing Act 1881, s. 9). The term ``acknowledgment'' is, in the United States, applied to the certificate of a public officer that an instrument was acknowledged before him to be the deed or act of the person who executed it. .
``Acknowledgment money'' is the sum paid in some parts of England by copyhold tenants on the death of the lord of the manor.
ACLAND, CHRISTIAN HENRIETTA CAROLINE (1750-1815), usually called Lady Harriet Acland, was born on the 3rd of January 1750, the daughter of the first earl of Ilchester. In 1770 she married John Dyke Acland, who as a member of parliament became a vigorous supporter of Lord North's policy towards the American colonies, and, entering the British army in 1774, served with Burgoyne's expedition as major in the 20th regiment of foot. Lady Hurriet accompanied her husband, and, when he was wounded at Ticonderoga, nursed him in his tent at the front. In the second battle of Saratoga Major Acland was again badly wounded and subsequently taken prisoner. Lady Harriet was determined to be with him, and underwent great hardship to accomplish her object, proving herself a courageous and devoted wife. A story has been told that being provided with a letter from General Burgoyne to the American general Gates, she went up the Hudson river in an open boat to the enemy's lines, arriving late in the evening. The American outposts threatened to fire into the boat if its occupants stirred, and Lady Hnrriet had to wait eight ``dark and cold hours,'' until the sun rose, when she at last received permission to join her husband. Major Acland died in 1778, and Lady Harriet on the 21st of July 1815.
ACLAND, SIR HENRY WENTWORTH, BART. (1815-1900), English physician and man of learning, was born near Exeter on the 23rd of August 1815, and was the fourth son of Sir Thomas Dyke Acland (1787-1871). Educated at Harrow and at Christ Church, Oxford, he was elected fellow of All Souls in 1840, and then studied medicine in London and Edinburgh. Returning to Oxford, he was appointed Lee's reader in anatomy at Christ Church in 1845, and in 1851 Radcliffe librarian and physician to the Radcliffe infirmary. Seven years later he became regius professor of medicine, a post which he retained till 1894. He was also a curator of the university galleries and of the Bodleian Library, and from 1858 to 1887 he represented his university on the General Medical Council, of which he served as president from 1874 to 1887. Hn was created a baronet in 1890, and ten years later, on the 16th of October 1900, he died at his house in Broad Street, Oxford. Acland took a leading part in the revival of the Oxford medical school and in introducing the study of natural science into the university. As Lee's reader he began to form a collection of anatomical and physiological preparations on the plan of John Hunter, and the establishment of the Oxford University museum, opened in 1861, as a centre for the encouragement of the study of science, especially in relation to medicine, was largely due to his efforts. ``To Henry Acland,'' said his lifelong friend, John Ruskin, ``physiology was an entrusted gospel of which he was the solitary preacher to the heathen,'' but on the other hand his thorough classical training preserved science at Oxford from too abrupt a severance from the humanities. In conjunction with Dean Liddell, he revolutionized the study of art and archaeology, so that the cultivation of these subjects, for which, as Ruskin declared, no one at Oxford cared before that time, began to flourish in the university. Acland was also interested in questions of public health. He served on the royal commission on sanitary laws in England and Wales in 1869, and published a study of the outbreak of cholera at Oxford in 1854, together with various pamphlets on sanitary matters. His memoir on the topography of the Troad, with panoramic plan (1839), was among the fruits of a cruise which he made in the Mediterranean for the sake of his health.
ACME (Gr. akme, point), the highest point attainable; first used as an English word by Ben Jonson.
ACMITE, or AEGIRITE, a mineral of the pyroxene (q.v.) group, which may be described as a soda-pyroxene, being essentially a sodium and ferric metasilicate, NAFe(SiO3)2. In its crystallographic characters it is close to ordinary pyroxene (augite and diopside), being monoclinic and having nearly the same angle between the prismatic cleavages. There are, however, important differences in the optical characters: the birefringence of acmite is negative, the pleochroism is strong and the extinction angle on the plane of symmetry measured to the vertical axis is small (3 deg. -5 deg. ). (The hardness is 6-6 1/2, and the specific gravity 3.55. Crystals are elongated in the direction of the vertical axis, and are blackish green (aegirite) or dark brown (acmite) in colour. Being isomorphous with augite, crystals intermediate in composition between augite or diopside and aegirite are not uncommon, and these are known as aegirine-augite or aegirine-diopside.
Acmite is a characteristic constituent of igneous rocks rich in soda, such as nepheline-syenites, phonolites, &c. It was first discovered as slender crystals, sometimes a foot in length, in the pegmatite veins of the granite of Rundemyr, near Kongsbeig in Rorway, and was named by F. Stromeyer in 1821 from the Gr. akme, a point, in allusion to the pointed terminations of the crystals. Aegirite (named from Aegir, the Scandinavian sea-god) was described in 1835 from the elaeolite-syenite of southern Norway. Although exhibiting certain varietal differences, the essential identity of acmite and aegirite has long been established, but the latter and more recent name is pethaps in more general use, especially among petrologists.
ACNE, a skin eruption produced by inflammation of the sebaceous glands and hair follicles, the essential point in the disease being the plugging of the mouths of the sebaceous follicles by a ``comedo,'' familiarly known as ``blackhead.'' It is now generally acknowledged that the cause of this disease is the organism known as bacillus acnes. It shows itself in the form of red pimples or papules, which may become pustular and be attended with considerable surrounding irritation of the skin. This affection is likewise most common in early adult life, and occurs on the chest and back as well as on the face, where it may, when of much extent, produce considerable disfigurement. It is apt to persist for months or even years, but usually in time disappears entirely, although slight traces may remain in the form of scars or stains upon the skin. Eruptions of this kind are sometimes produced by the continued internal use of certain drugs, such as the iodide or bromide of potassium. In treating this condition the face should first of all be held over steaming water for several minutes, and then thoroughly bathed. The blackheads should next be removed, not with the finger-nail, but with an inexpensive little instrument known as the ``comedo expressor.'' When the more noticeable of the blackheads have been expressed, the face should be firmly rubbed for three or four minutes with a lather made from a special soap composed of sulphur, camphor and balsam of Peru. Any lather remaining on the face at the end of this time should be wiped off with a soft handkerchief. As this treatment might give rise to some irritation of the skin, it should be replaced every fourth night by a simple application of cold cream. Of drugs used internally sulphate of calcium, in pill, 1/6 grain three times a day, is a very useful adjunct to the preceding. The patient should take plenty of exercise in the fresh air, a very simple but nourishing diet, and, if present, constipation and anaemia must be suitably treated.
Rosacea, popularly known as acne rosacea, is a more severe and troublesome disorder, a true dermatitis with no relation to the foregoing, and in most cases secondary to seborrhea of the scalp. It is characterized by great redness of the nose and cheeks, accompanied by pustular enlargements on the surface of the skin, which produce marked disfigurement. Although often seen in persons who live too freely, it is by no means confined to such, but may arise in connexion with disturbances of the general health, especially of the function of digestion, and in females with menstrual disorders. It is apt to be exceedingly intractable to treatment, which is here too, as in the preceding form, partly local and partly constitutional. Of internal remedies preparations of iodine and of arsenic are sometimes found of service.
ACOEMETI (Gr. akoimetos, sleepless), an order of Eastern monks who celebrated the divine service without intermission day or night. This was done by dividing the communities into choirs, which relieved each other by turn in the church. Their first monastery was established on the Euphrates, in the beginning of the 5th century, and soon afterwards one was founded in Constantinople. Here also, c. 460, was founded by the consular Studius the famous monastery of the Studium, which was put in the hands of the Acoemeti and became their chief house, so that they were sometimes called Studites. At Agaunum (St Maurice in the Valais) a monastery was founded by the Burgundian king Sigismund, in 515, in which the perpetual office was kept up; but it is doubtful whether this had any connexion with the Eastern Acoemeti.
The Constantinopolitan Acoemeti took a prominent part in the Christological controversies of the 5th and 6th centuries, at first strenuously opposing Acacius, patriarch of Constantinople, in his attempted compromise with the monophysites; but afterwards, in Justinian's reign, falling under ecclesiastical censure for Nestorian tendencies.
See the article in Dictionary of Christian Antiquities; Wetzer und Welte, Kirchenlexicon (2nd ed.); and Herzog-Hauck, Realencyklopadie (3rd ed.); also the general histories of the time. (E. C. B.)
ACOLYTE (Gr.akolouthos, follower), the last of the four minor orders in the Roman Church. As an office it appears to be of local origin, and is entirely unknown in the Eastern Church, with the exception of the Armenians who borrowed it from the West. Before the council of Nicaea (325) it was only to be found at Rome and Carthage. When in 251 Pope Cornelius, in a letter to Fabius of Antioch, mentions among the Roman clergy forty-two acolytes, placing them after the subdeacons and before the other minor officials (see Eusebius, Hist. Ecc. lib. v. cap. 43), he gives no hint that the office was a new one, but speaks of them as holding an already established position. Their institution has therefore to be sought for at an earlier date than his pontificate. It is possible that the Liber Pontificalis refers to the office under the Latin synonym, when it says of Pope Victor (186—197) that he made sequentes cleros, a term—-sequens—-which Pope Gaius (283—293) uses in the sense of acolyte. While the office was well known in Rome, there is nothing to prove that it was also an order through which, as to-day, every candidate to the priesthood must pass. The contrary is a fact proved by many monumental inscriptions and authentic statements. Though the office is found at Carthage, and St Cyprian (200?-258) makes many references to acolytes, whom he used to carry his letters, this seems to be the only place in Africa where they were known. Tertullian, while speaking of readers and exorcists, says nothing about acolytes; neither does St Augustine. The Irish Church did not know them; and in Spain the council of Toledo (400) makes no mention either of the office or of the order. The Statuta Ecclesiae Antiqua (falsely called the Canons of the Fourth Council of Carthage in 397), a Gallican collection, originating in the province of Arles at the beginning of the 6th century, mentions the acolyte, but does not give, as in the case of the other orders, any form for the ordination. The Roman books are silent, and there is no mention of it in the collection known as the Leonine Sacramentary; while in the so-called Gelasian Massbook, which as we have it, is full of Gallican additions made to St Gregory's reform, there is the same silence, though in one MS. of the 10th century given by Muratori we find a form for the ordination of an acolyte. While there is frequent mention of the acolyte's office in the Ordines Romani, it is only in the Ordo VIII. (which is not earlier than the 7th century) that we find the very simple form for admitting an acolyte to his office. At the end of the mass the cleric, clad in chasuble and stole and bearing a linen bag on one arm, comes before the pope or bishop and receives a blessing. There is no collation of power or order but a simple admission to an office. The evidence available, therefore, points to the fact that the acolyte was only a local office and was not a necessary step or order for every candidate. In England, though the ecclesiastical organization came from Rome and was directed by Romans, we find no trace of such an office or order until the time of Ecgbert of York (767), the friand of Alcuin and therefore subject to Gallican influence. The Pontifical known as Ecgbert's shows that it was then in use both as an office and as an order, and Aelfric (1006) in both his pastoral epistle and canons mentions the acolyte. The conclusion, then, which seems warranted by the evidence, is that the acolyte was an office only at Rome, and, becoming an order in the Gallican Church, found its way as such into the Roman books at some period before the fusion of the two rites under Charlemagne.
The duties of the acolyte, as given in the Roman Pontifical, are identical with those mentioned in the Statuta Ecclesiae Antiqua of Arles: ``It is the duty of acolytes to carry the candlesticks, to light the lamps of the church, to administer wine and water for the Eucharist.'' It might seem, from the number forty-two mentioned by Pope Cornelius, that at Rome the acolytes were divided among the seven ecclesiastical regions of the city; but we have no proof that, at that date, there were six acolytes attached to each region. From the ancient division of the Roman acolytes into Dalatini, or those in attendance on the pope at the Lateran palace, Stationarii, or those who served at the churches where there was a ``station,'' and Regionarii, or those attached directly to the regiona, it would seem that the number forty-two was only the actual number then existing and not an official number. We get a glimpse of their duties from the Ordines Romani. When the pope rode in procession to the station an acolyte, on foot, preceded him, bearing the holy chrism; and at the church seven regionary acolytes with candles went before him in the procession to the altar, while two others, bearing the vessel that contained a pre-consecrated Host, presented it for his adoration. During the mass an acolyte bore the thurible (Ordo VI.) and three assisted at the washing of the hands. At the moment of communion the acolytes received in linen bags the consecrated Hosts to carry to the assisting priests. This office of bearing the sacrament is an ancient one, and is mentioned in the legend of Tarcisius, the Roman acolyte, who was martyred on the Appian Way while carrying the Hosts from the catacombs. The official dress of the acolyte, according to Ordo V., was a close-fitting linen garment (camisia) girt about him, a napkin hanging from the left side, a white tunic, a stole (orarium) and a chasuble (planeta) which he took off when he sang on the steps of the ambone.
At the present day, despite the earnest wish of the council of Trent (Sess. xxiii. cap. 17 d.r.), the acolyte, while remaining an order, has ceased to be essentially a clerical office, since the duties are now performed, almost everywhere, by laymen. The office has been revived, though unofficially, in the Church of England, as a result of the Tractarian movement.
See Morin, Commentarius in sacris Ecclesiae ordinationibus(Antwerp, 1685), ii. p. 209, iii. p. 152; Martene, De AntiquisEcclesiae ritibus (Antwerp, 1739), ii. pp. 47 and 86; Mabillon,Musaeum Italicum II. for the Ordines Romani; Muratori,Liturgia Romana Vetus; Cabrol, Dictionnaire d'archeologiechretisnne et de liturgie, vol. i. col. 348-536.-. (E. TN.)
ACOMINATUS (AKOMINATOS), MICHAEL (c. 1140-1220), Byzantine writer and ecclesiastic, was born at Chonae (the ancient Colossae). At an early age he studied at Constantinople, and about 1175 was appointed archbishop of Athens. After the capture of Constantinople by the Franks and the establishment of the Latin empire (1204), he retired to the island of Coos, where he died. He was a versatile writer, and composed homilies, speeches and poems, which, with his correspondence, throw considerable light upon the miserable condition of Attica and Athens at the time. His memorial to Alexis III. Angelus on the abuses of Byzantine administration, the poetical lament over the degeneracy of Athens and the monodes on his brother Nicetas and Eustathius, archbishop of Thessalonica, deserve special mention.
Edition of his works by S. Lambros (1879—1880); Migne, Patrologia Graeca, cxl.; see also A. Ellissen, Michael Akominatos (1886), containing several pieces with German translation; F. Gregorovius, Geschichte der Stadt Athen im Mittelalter, i. (1889); G. Finlay, History of Greece, iv. pp. 133-134 (1877).
His younger brother NICETAS (Niketas), sometimes called CHONIATES, who accompanied him to Constantinople, took up politics as a career. He held several appointments under the Angelus emperors (amongst them that of ``great logothete'' or chancellor) and was governor of the ``theme'' of Philippopolis at a critical period. After the fall of Constantinople he fled to Nicaea, where he settled at the court of the emperor Theodorus Lascaris, and devoted himself to literature. He died between 1210 and 1220. His chief work is his History, in 21 books, of the period from 1180 to 1206. In spite of its florid and bombastic style, it is of considerable value as a record (on the whole impartial) of events of which he was either an eye-witness or had heard at first hand. Its most interesting portion is the description of the capture of Constantinople, which should be read with Villehardouin's and Paolo Rannusio's works on the same subject. The little treatise On the Statues destroyed by thc Latins (perhaps, as we have it, altered by a later writer) is of special interest to the archaeologist. His dogmatic work( Thesauros 'Orthodoxias, Thesaurus Orthodoxae Fidei), although it is extant in a complete form in MS., has only been published in part. It is one of the chief authorities for the heresies and heretical writers of the 12th century.
Editions: History, editio princeps, H. Wolf (1557); and in the Bonn Corpus Scriptorum Hist. Byz., 1st ed.,Bekker (1835); Rhetorical Pieces in C. Sathas, Mesaionike Bibliotheke, i. (1872); Thesaurus in Migne, Patrologia Graeca, cxxxix., cxl.; see also C. A. Sainte-Beuve, ``Geoffroy de Villehardouin'' in Causeries du Lundi, ix.; S. Reinach, ``La fin de l'empire grec'' in Esquisses Archeologiques (1888); C. Neumann, Griechische Geschichtsschreiber im 12. Jahrhundert (1888); Gibbon, Decline and Fall, ch. lx.; and (for both Michael and Nicetas) C. Krumbacher, Geschichte der byzantinischen Litteratur (1897).
ACONCAGUA, a small northern province of central Chile, bounded N. by Coquimbo, E. by Argentina, S. by Santiago and Valparaiso and W. by the Pacific. Its area is officially computed at 5487 sq. m. Pop. (1895) 113,165; (1902, official estimate based on civil registry returns) 131,255. The province is very mountainous, and is traversed from east to west by the broad valley of the Aconcagua river. The climate is hot and dry, the rainfall being too small to influence climatic conditions. The valleys are highly fertile, and where irrigation is employed large crops are easily raised. Beyond the limits of irrigation the country is semi-barren. Alfalfa and grapes are the principal products, and considerable attention is given to the cultivation of other fruits, such as figs, peaches and melons. The ``Vale of Quillota,'' through which the railway passes between Valparaiso and Santiago, is celebrated for its gardens. The Aconcagua river rises on the southern slope of the volcano Aconcagua, flows eastward through a broad valley, or bay in the mountains, and enters the Pacific 12 m. north of Valparaiso. The river has a course of about 200 m., and its waters irrigate the best and most populous part of the province. Two other rivers—the Ligua and Choapa—traverse the province, the latter forming the northern boundary line. The capital is San Felipe, on the Aconcagua river; it had a population of 11,313 in 1895, and an estimated population of 11,660 in 1902. The other chief town is Santa Rosa de los Andes (est. pop. 6854), which is a principal station on the Transandine branch of the state railway. The only port in the province is Los Vilos, in lat. 32 deg. S., from which a railway 40 m. long runs north-east to the valley of the Choapa. Another short line connects Cabildo, in the valley of the Ligua, with the state railway.
ACONCIO, GIACOMO (1492-1566?), pioneer of religious toleration, was born at Trent, it is said, on the 7th of September 1492. He was one of the Italians like Peter Martyr and Bernardino Ochino who repudiated papal doctrine and ultimately found refuge in England. Like them, his revolt against Romanism took an extremer form than Lutheranism, and after a temporary residence in Switzerland and at Strassburg, he arrived in England soon after Elizabeth's accession. He had studied law and theology, but his profession was that of an engineer, and in this capacity he found employment with the English government. He was granted an annuity of L. 60 on the 27th of February 1560, and letters of naturalization on the 8th of October 1561 (Cal. State Papers, Dom. Ser., Addenda, 1547—1566, p. 495), and was for some time occupied with draining Plumstead marshes, for which object various acts of parliament were passed at this time (Lords' Journals, vol. i., and Commons' Journals, vol. i., passim). In 1564 he was sent to report on the fortifications of Berwick (Cal. St. Pap. For Ser. 1564-1565, passim; Acts P.C., 1558-1570, p. 146); his report is now in thc Record Office (C.S.P. For., 1564-1565, No. 512).
But his real importance depends upon his contribution to the history of religious toleration. Before reaching England he had published a treatise on the methods of investigation, De Methodo, hoc est, de recte investigandarum tradendarumque Scientiarum ratione (Basel, 1558, 8vo); and his critical spirit placed him outside all the recognized religious societies of his time. On his arrival in London he had joined the Dutch Reformed Church in Austin Friars, but he was ``infected with Anabaptistical and Arian opinions'' and was excluded from the sacrament by Grindal, bishop of London. The real nature of his heterodoxy is revealed in his Stratagemata Satanae, published in 1565 and translated into various languages. The ``stratagems of Satan'' are the dogmatic creeds which rent the Christian church. Aconcio sought to find the common denominator of the various creeds; this was essential doctrine, the rest was immaterial. To arrive at this common basis, he had to reduce dogma to a low level, and his result was generally repudiated. Even Selden applied to Aconcio the remark ubi bene, nil melius; ubi male, nemo pejus. The dedication of such a work to Queen Elizabeth illustrates the tolerance or religious laxity during the early years of her reign. Aconcio found another patron in the earl of Leicester, and died about 1566.
AUTHORITIES.—Gough's Index to Parker Soc. Publ.;Strype's Grindal, pp. 62, 66; Bayle's Dictionnaire; G.Tiraboschi, Storia della lett. italiana (Florence,1805—1813); Osterreichisches Biogr. Lexikon;Nouvelle biogr. generale; Dict. Nat. Biogr. (A. F. P.)
ACONITE (Aconitum), a genus of plants belonging to the natural order Ranunculaceae, the buttercup family, commonly known as aconite, monkshood or wolfsbane, and embracing about 60 species, chiefly natives of the mountainous parts of the northern hemisphere. They are distinguished by having one of the five blue or yellow coloured sepals (the posterior one) in the form of a helmet; hence the English name monkshood. Two of the petals placed under the hood of the calyx are supported on long stalks, and have a hollow spur at their apex, containing honey. They are handsome plants, the tall stem being crowned by racemes of showy flowers. Aconitum Napellus, common monkshood, is a doubtful native of Britain, and is of therapeutic and toxicological importance. Its roots have occasionally been mistaken for horse-radish. The aconite has a short underground stem, from which dark-coloured tapering roots descend. The crown or upper portion of the root gives rise to new plants. When put to the lip, the juice of the aconite root produces a feeling of numbness and tingling. The horse-radish root, which belongs to the natural order Cruciferae, is much longer than that of the aconite, and it is not tapering; its colour is yellowish, and the top of the root has the remains of the leaves on it.
Many species of aconite are cultivated in gardens, some having blue and others yellow flowers. Aconitum lycoctonum, wolfsbane, is a yellow-flowered species common on the Alps of Switzerland. The roots of Aconitum ferox supply the famous Indian (Nepal) poison called bikh, bish or nabee. It contains considerable quantities of the alkaloid pseudaconitine, which is the most deadly poison known. Aconitum palmatum yields another of the celebrated bikh poisons. The root of Aconitum luridum, of the Himalayas, is said to be as virulent as that of A. ferox or A. Napellus. As garden plants the aconites are very ornamental, hardy perennials. They thrive well in any ordinary garden soil, and will grow beneath the shade of trees. They are easily propagated by divisions of the root or by seeds; great care should be taken not to leave pieces of the root about owing to its very poisonous character.
Chemistry.—-The active principle of Aconitum Napellus is the alkaloid aconitine, first examined by P. L. Geiger and Hesse (Ann., 1834, 7, p. 267), Alder Wright and A. B, Luff obtained apoaconitine, aconine and benzoic acid by hydrolysis; while, in 1802, C. Ehrenberg and A. Purfurst (Journ. Prat. Chem., 1892, 45, p. 604) observed acetic acid as a hydrolytic product. This, and allied alkaloids, have formed the subject of many investigations by Wyndham Dunstan and his pupils in England, and by Martin Freund and Paul Beck in Berlin. But their constitution is not yet solved, there even being some divergence of opinion as to their empirical formulae, Aconitine (C33H45NO13, according to Dunstan; C34H47NO11, according to Freund) is a crystalline base, soluble in alcohol, but very sparingly in water; its alcoholic solution is dextrorotatory, but its salts are laevorotatory. When heated it loses water and forms pyraconitine. Hydrolysis gives acetic acid and benzaconine, the chief constituent of the alkaloids picraconitine and napelline; further hydrolysis gives aconine. Pseudaconitine, obtained from Aconitum ferox, gives on hydrolysis acetic acid and veratrylpseudaconine, the latter of which suffers further hydrolysis to veratric acid and pseudaconine. Japaconitine, obtained from the Japanese aconites, known locally as ``kuza-uzu,'' hydrolyses to japbenzaconine, which further breaks down to benzoic acid and japaconine. Other related alkaloids are lycaconitine and myoctonine which occur in wolfsbane, Aconitum lycoctonum. The usual test for solutions of aconitine consists in slight acidulation with acetic acid and addition of potassium permanganate, which causes the formation of a red crystalline precipitate. In 1905, Dunstan and his collaborators discovered two new aconite alkaloids, indaconitine in ``mohri'' (Aconitum chasmanthum, Stapf), and bikhaconitine in ``bikh'' (Aconitum spicatum); he also proposes to classify these alkaloids according to whether they yield benzoic or veratric acid on hydrolysis (Jour. Chem. Soc., 1905, 87, pp. 1620, 1650).
From the root of Aconitum Napellus are prepared a liniment and a tincture. The dose of the latter (Brit. Pharmacop.) is of importance as being exceptionally small, for it is not advisable to give more than at most five drops at a time. The official preparation is an ointment which contains one part of the alkaloid in fifty. It must be used with extreme care, and in small quantities, and it must not be used at all where cuts or cracks are present in the skin.
Pharmacology of Aconite and Aconitine.—-Aconite first stimulates and later paralyses the nerves of pain, touch and temperature, if applied to the skin, broken or unbroken, or to a mucous membrane; the initial tingling therefore gives place to a long-continued anaesthetic action. Taken internally aconite acts very notably on the circulation, the respiration and the nervous system. The pulse is slowed, the number of beats per minute being actually reduced, under considerable doses, to forty, or even thirty, per minute. The blood-pressure synchronously falls, and the heart is arrested in diastole. Immediately before arrest the heart may beat much faster than normally, though with extreme irregularity, and in the lower animals the auricles may be observed occasionally to miss a beat, as in poisoning by veratrine and colchicum. The action of aconitine on the circulation is due to an initial stimulation of the cardio-inhibitory centre in the medulla oblongata (at the root of the vagus nerves), and later to a directly toxic influence on the nerve-ganglia and muscular fibres of the heart itself. The fall in blood-pressure is not due to any direct influence on the vessels. The respiration becomes slower owing to a paralytic action on the respiratory centre and, in warm-blooded animals, death is due to this action, the respiration being arrested before the action of the heart. Aconite further depresses the activity of all nerve-terminals, the sensory being affected before the motor. In small doses it therefore tends to relieve pain, if this be present. The activity of the spinal cord is similarly depressed. The pupil is at first contracted, and afterwards dilated. The cerebrum is totally unaffected by aconite, consciousness and the intelligence remaining normal to the last. The antipyretic action which considerable doses of aconite display is not specific, but is the result of its influence on the circulation and respiration and of its slight diaphoretic action.
Therapeutics.—-The indications for its employment are limited, but definite. It is of undoubted value as a local anodyne in sciatica and neuralgia, especially in ordinary facial or trigeminal neuralgia. The best method of application is by rubbing in a small quantity of the aconitine ointment until numbness is felt, but the costliness of this preparation causes the use of the aconite liniment to be commonly resorted to. This should be painted on the affected part with a camel's hair brush dipped in chloroform, which facilitates the absorption of the alkaloid. Aconite is indicated for internal administration whenever it is desirable to depress the action of the heart in the course of a fever. Formerly used in every fever, and even in the septic states that constantly followed surgical operations in the pre-Listerian epoch, aconite is now employed only in the earliest stage of the less serious fevers, such as acute tonsilitis, bronchitis and, notably, laryngitis. The extreme pain and rapid swelling of the vocal cords—-with threatened obstruction to the respiration that characterize acute laryngitis may often be relieved by the sedative action of this drug upon the circulation. In order to reduce the pulse to its normal rate in these cases, without at the same time lessening the power of the heart, the drug must be given in doses of about two minims of the tincture every half-hour and then every hour until the pulse falls to the normal rate. Thereafter the drug must be discontinued. It is probably never right to give aconite in doses much larger than that named. There is one condition of the heart itself in which aconite is sometimes useful. Whilst absolutely contra-indicated in all cases of valvular disease, it is of value in cases of cardiac hypertrophy with over-action. But the practitioner must be assured that neither valvular lesion nor degeneration of the myocardium is present.
Toxicology.—-In a few minutes after the introduction of a poisonous dose of aconite, marked symptoms supervene. The initial signs of poisoning are referable to the alimentary canal. There is a sensation of burning, tingling and numbness in the mouth, and of burning in the abdomen. Death usually supervenes before a numbing effect on the intestine can be observed. After about an hour there is severe vomiting. Much motor weakness and cutaneous sensations similar to those above described soon follow. The pulse and respiration steadily fail, death occurring from asphyxia. As in strychnine poisoning, the patient is conscious and clear-minded to the last. The only post-mortem signs are those of asphyxia. The treatment is to empty the stomach by tube or by a non-depressant emetic. The physiological antidotes are atropine and digitalin or strophanthin, which should be injected subcutaneously in maximal doses. Alcohol, strychnine and warmth must also be employed.
ACONTIUS (Gr. Akontios), in Greek legend, a beautiful youth of the island of Ceos, the hero of a love-story told by Callimachus in a poem now lost, which forms the subject of two of Ovid's Heroides (xx., xxi.). During the festival of Artemis at Deles, Acontius saw Cydippe, a well-born Athenian maiden of whom he was enamoured, sitting in the temple of the goddess. He wrote on an apple the words, ``I swear by the sacred shrine of the goddess that I will marry you,'' and threw it at her feet. She picked it up, and mechanically read the words aloud, which amounted to a solemn undertaking to carry them out. Unaware of this, she treated Acontius with contempt; but, although she was betrothed more than once, she always fell ill before the wedding took place. The Delphic oracle at last declared the cause of her illnesses to be the wrath of the offended goddess; whereupon her father consented to her marriage with Acontius (Aristaenetus, Epistolae, i. 10; Antoninus Liberalis, Metamorphoses, i., tells the story with different names).
ACORN, the fruit of the oak-tree; a word also used, by analogy with the shape, in nautical language, for a piece of wood keeping the vane on the mast-head. The etymology of the word (earlier akerne, and acharn) is well discussed in the New English Dictionary. It is derived from a word (Goth. akran) which meant ``fruit,'' originally ``of the unenclosed land,'' and so of the most important forest produce, thc oak. Chaucer speaks of ``achornes of okes.'' By degrees, popular etymology connected the word both with ``corn'' and ``oak-horn,'' and the spelling changed accordingly.
ACORUS CALAMUS, sweet-sedge or sweet-flag, a plant of the natural order Araceae, which shares with the Cuckoo Pint (Arum) the representation in Britain of that order of Monocotyledons. The name is derived from acorus, Gr. akoros, the classical name for the plant. It was the Calamus aromaticus of the medieval druggists and perhaps of the ancients, though the latter has been referred by some to the Citron grass, Andropogon Nardus. The spice ``Calamus'' or ``Sweet-cane'' of the Scriptures, one of the ingredients of the holy anointing oil of the Jews, was perhaps one of the fragrant species of Andropogon. The plant is a herbaceous perennial with a long, branched root-stock creeping through the mud, about 3/4 inch thick, with short joints and large brownish leaf-scars. At the ends of the branches are tufts of flat, sword-like, sweet-scented leaves 3 or 4 ft. long and about an inch wide, closely arranged in two rows as in the true Flag (Iris); the tall, flowering stems (scapes), which very much resemble the leaves, bear an apparently lateral, blunt, tapering spike of densely packed, very small flowers. A long leaf (spathe) borne immediately below the spike forms an apparent continuation of the scape, though really a lateral outgrowth from it, the spike of flowers being terminal. The plant has a wide distribution, growing in wet situations in the Himalayas, North America, Siberia and various parts of Europe, including England, and has been naturalized in Scotland and Ireland. Though regarded as a native in most counties of England at the present day, where it is now found thoroughly wild on sides of ditches, ponds and rivers, and very abundantly in some districts, it is probably not indigenous. It seems to have been spread in western and central Europe from about the end of the 16th century by means of botanic gardens. The botanist Clusius (Charles de l'Escluse or Lecluse, 1526-1609) first cultivated it at Vienna from a root received from Asia Minor in 1574, and distributed it to other botanists in central and western Europe, and it was probably introduced into England about 1596 by the herbalist Gerard. It is very readily propagated by means of its branching root-stock. It has an agreeable odour, and has been used medicinally. The starchy matter contained in its rhizome is associated with a fragrant oil, and it is used as hair-powder. Sir J. E. Smith (Eng. Flora, ii. 158, 2nd ed., 1828) mentions it as a popular remedy in Norfolk for ague. In India it is used as an insectifuge, and is administered in infantile diarrhoea. It is an ingredient in pot-pourri, is employed for flavouring beer and is chewed to clear the voice; and its volatile oil is employed by makers of snuff and aromatic vinegar. The rhizome of Acorus Calamus is sometimes adulterated with that of Iris Pseudacorus, which, however, is distinguishable by its lack of odour, a stringent taste and dark colour.
ACOSTA, JOSE DE (1539?—1600), Spanish author, was born at Medina del Campo about the year 1539. He joined the Jesuits in 1551, and in 1571 was sent as a missionary to Peru; he acted as provincial of his order from 1576 to 1581, was appointed theological adviser to the council of Lima in 1582, and in 1583 published a catechism in Quichua and Aymara—the first book printed in Peru. Returning to Spain in 1587, and placing himself at the head of the opposition to Acquaviva, Acosta was imprisoned in 1592—1593; on his submission in 1594 he became superior of the Jesuits at Valladolid, and in 1598 rector of the Jesuit college at Salamanca, where he died on the 15th of February 1600. His treatise De natura novi orbis libri duo (Salamanca, 1588-1589) may be regarded as the preliminary draft of his celebrated Historia natural y moral de las Indias (Seville, 1590) which was speedily translated into Italian (1596), French (1597), Dutch (1598), German (1601), Latin (1602) and English (1604) The Historia is in three sections: books I. and II. deal with generalities; books III. and IV. with the physical geography and natural history of Mexico and Peru; books V., VI. and VII. with the religious and political institutions of the aborigines. Apart from his sophistical defence of Spanish colonial policy, Acosta deserves high praise as an acute and diligent observer whose numerous new and valuable data are set forth in a vivid style. Among his other publications are De procuranda salute Indorum libri sex (Salamanca, 1588), De Christo revelato libri novem (Rome, 1590), De temporibus novissimis libri quatuor (Rome, 1590), and three volumes of sermons issued respectively in 1596, 1597 and 1599.
AUTHORITIES.—-Jose R. Carricido, El P. Jose de Acosta y su importancia en La literatura cientifica espanola (Madrid, 1899); C. Sommervogel, Bibliotheque de La Compagnie de Jesus, Premiere Partie (Brussels and Paris, 1890), vol. i., col. 31-42; and Edward Grimston's translation of the Historia reprinted (1880) for the Hakluyt Society with introduction and notes by Sir Clements R. Markham. (J. F.-K.)
ACOSTA, URIEL (d. 1647), a Portuguese Jew of noble family, was born at Oporto towards the close of the 16th century. His father being a convert to Christianity, Uriel was brought up in the Roman Catholic faith, and strictly observed the rites of the church till the course of his inquiries led him, after much painful doubt, to abandon the religion of his youth for Judaism. Passing over to Amsterdam, he was received into the synagogue, having his name changed from Gabriel to Uriel. His wayward disposition found, however, no satisfaction in the Jewish fold. He came into conflict with the authorities of the synagogue and was excommunicated. Unlike Spinoza (who was about fifteen at the time of Acosta's death), Acosta was not strong enough to stand alone. Wearied by his melancholy isolation, he was driven to seek a return to the Jewish communion. Having recanted his heresies, he was readmitted after an excommunication of fifteen years, but was soon excommunicated a second time. After seven years of exclusion, he once more sought admission, and, on passing through a humiliating penance, was again received. His vacillating autobiography, Exemplar Humanae Vitae, was published with a ``refutation'' by Limborch in 1687, and republished in 1847. In this brief work Acosta declares his opposition both to Christianity and Judaism, though he speaks with the more bitterness of the latter religion. The only authority which he admits is the lex naturae. Acosta was not an original thinker, but he stands in the direct line of the rational Deists. His history forms the subject of a tale and of a tragedy by Gutzkow. Acosta committed suicide in 1647. The significance of his career has been much exaggerated.
ACOTYLEDONES, the name given by Antoine Laurent de Jussieu in 1789 to the lowest class in his Natural System of Botany, embracing flowerless plants, such as ferns, lycopods, horse-tails, mosses, liverworts, sea-weeds, lichens and fungi. The name is derived from the absence of a seed-leaf or cotyledon. Flowering plants bear a seed containing an embryo, with usually one or two cotyledons, or seed-leaves; while in flowerless plants there is no seed and therefore no true cotyledon. The term is synonymous with Cryptogams, by which it was replaced in later systems of classification.
ACOUSTICS (from the Gr. akouein to hear), a title frequently given to the science of sound, that is, to the description and theory of the phenomena which give rise to the sensation of sound (q.v.). The term ``acoustics'' might, however, with advantage be reserved for the aspect of the subject more immediately connected with hearing. Thus we may speak appropriately of the acoustic quality of a room or hall, describing it as good or bad acoustically, according as speaking is heard in it easily or with difficulty. When a room has bad acoustic quality we can almost always assign the fault to large smooth surfaces on the walls, floor or ceiling, which reflect or echo the voice of the speaker so that the direct waves sent out by him at any instant are received by a hearer with the waves sent out previously and reflected at these smooth surfaces. The syllables overlap, and the hearing is confused. The acoustic quality of a room may be improved by breaking up the smooth surfaces by curtains or by arrangement of furniture. The echo is then broken up into small waves, none of which may be sufficiently distinct to interfere with the direct voice. Sometimes a sounding-board over the head of a speaker improves the hearing probably by preventing echo from a smooth wall behind him. A large bare floor is undoubtedly bad for acoustics, for when a room is filled by an audience the hearing is much improved Wires are frequently stretched across a room overhead, probably with the idea that they will prevent the voice from reaching the roof and being reflected there, but there is no reason to suppose that they are efficient. The only cure appears to consist in breaking up the reflecting surfaces so that the reflexion shall be much less regular and distinct. Probably drapery assists by absorbing the sound to some extent, and thus it lessens the echo besides breaking it up. (J. H. P.)
ACQUI, a city and episcopal see of Piedmont, Italy, in the province of Alessandria; from the town of that name it is 21 m. S.S.W. by rail. Pop. (1901) 13,786. Its warm sulphur springs are still resorted to; under the name of Aquae Statiellae they were famous in Roman times, and Paulus Diaconus and Liutprand speak of the ancient bath establishment. In the neighbourhood of the town are remains of the aqueduct which supplied it. The place was connected by road with Alba Pompeia and Augusta Taurinorum. The tribe of the Statielli, to whom the district belonged, had joined the Romans at an early period, but was attacked in 173 and in part transferred to the north of the Po. The town possesses a fine Gothic cathedral.
ACRE, or AQUIRY, a river of Brazil and principal tributary of the Purus, rising on the Bolivian frontier and flowing easterly and northerly to a junction with the Purus at 8 deg. 45' S. lat. The name is also applied to a district situated on the same river and on the former (1867) boundary line between Bolivia and Brazil. The region, which abounds in valuable rubber forests, was settled by Bolivians between 1870 and 1878, but was invaded by Brazilian rubber collectors during the next decade and became tributary to the rubber markets of Manaos and Para. In 1899 the Bolivian government established a custom-house at Puerto Alonso, on the Acre river, for the collection of export duties on rubber, which precipitated a conflict with the Brazilian settlers and finally brought about a boundary dispute between the two republics. In July 1899 the Acreanos declared their independence and set up a republic of their own, but in the following March they were reduced to submission by Brazil. Various disorders followed until Brazil decided to occupy Puerto Alonso with a military force. The boundary dispute was finally settled at Petropolis on the 17th of November 1903 through the purchase by Brazil of the rubber-producing territory south to about the 11th parallel, estimated at more than 60,000 sq. m.
ACRE, Akka, or ST JEAN D'ACRE, the chief town of a governmental district of Palestine which includes Haifa, Nazareth and Tiberias. It stands on a low promontory at the northern extremity of the Bay of Acre, 80 m. N. N.W. from Jerusalem, and 25 m. S. of Tyre. The population is about 11,000; 8000 being Moslems, the remainder Christians, Jews, &c. It was long regarded as the ``Key of Palestine,'' on account of its commanding position on the shore of the broad plain that joins the inland plain of Esdraelon, and so affords the easiest entrance to the interior of the country. But trade is now passing over to Haifa, at the south side of the bay, as its harbour offers a safer roadstead, and is a regular calling.place for steamers. Business, rapidly declining, is still carried on in wheat, maize, oil, sesame, &c., in the town market. There are few buildings of interest, owing to the frequent destructions the town has undergone. The wall, which is now ruinous and has but one gate, dates from the crusaders: the mosque was built by Jezzar Pasha (d. 1804) from materials taken from Caesarea Palaestina: his tomb is within. Acre is the seat of the head of the Babist religion.
History.—Few towns have had a more chequered or calamitous history. Of great antiquity, it is probably to be identified with the Aak of the tribute-lists of Tethmosis (Thothmes) III (c. 1500 B.C.), and it is certainly the Akka of the Tell el-Amarna correspondence. To the Hebrews it was known as Acco (Revised Version spelling), but it is mentioned only once in the Old Testament, namely Judges i. 31, as one of the places from which the Israelites did not drive out the Canaanite inhabitants. Theoretically it was in the territory of the tribe of Asher, and Josephus assigns it by name to the district of one of Solomon's provincial governors. Throughout the period of Hebrew domination, however, its political connexions were always with Syria rather than with Palestine proper: thus, about 725 B.C. it joined Sidon and Tyre in a revolt against Shalmaneser IV. It had a stormy experience during the three centuries preceding the Christian era. The Greek historians name it Ake (Josephus calls it also Akre); but the name was changed to Ptolemais, probably by Ptolemy Soter, after the partition of the kingdom of Alexander. Strabo refers to the city as once a rendezvous for the Persians in their expeditions against Egypt. About 165 B.C. Simon Maccabaeus defeated the Syrians in many battles in Galilee, and drove them into Ptolemais. About 153 B.C. Alexander Balas, son of Antiochus Epiphanes, contesting the Syrian crown with Demetrius, seized the city, which opened its gates to him. Demetrius offered many bribes to the Maccabees to obtain Jewish support against his rival, including the revenues of Ptolemais for the benefit of the Temple, but in vain. Jonathan threw in his lot with Alexander, and in 150 B.C. he was received by him with great honour in Ptolemais. Some years later, however, Tryphon, an officer of the Syrians, who had grown suspicious of the Maccabees, enticed Jonathan into Ptolemais and there treacherously took him prisoner. The city was also assaulted and captured by Alexander Jannaeus, by Cleopatra and by Tigranes. Here Herod built a gymnasium, and here the Jews met Petronius, sent to set up statues of the emperor in the Temple, and persuaded him to turn back. St Paul spent a day in Ptolemais. The Arabs captured the city in A.D. 638, and lost it to the crusaders in 1110. The latter made the town their chief port in Palestine. It was re-taken by Saladin in 1187, besieged by Guy de Lusignan in 1189 (see below), and again captured by Richard Coeur de Lion in 1191. In 1229 it was placed under the control of the knights of St John (whence one of its alternative names), but finally lost by the Franks in 1291. The Turks under Sultan Selim I. captured the city in 1517, after which it fell into almost total decay. Maundrell in 1697 found it a complete ruin, save for a khan occupied by some French merchants, a mosque and a few poor cottages. Towards the end of the 18th century it seems to have revived under the comparatively beneficent rule of Dhahar el-Amir, the local sheikh: his successor, Jezzar Pasha, governor of Damascus, improved and fortified it, but by heavy imposts secured for himself all the benefits derived from his improvements. About 1780 Jezzar peremptorily banished the French trading colony, in spite of protests from the French government, and refused to receive a consul. In 1799 Napoleon, in pursuance of his scheme for raising a Syrian rebellion against Turkish domination, appeared before Acre, but after a siege of two months (March—May) was repulsed by the Turks, aided by Sir W. Sidney Smith and a force of British sailors. Jezzar was succeeded on his death by his son Suleiman, under whose milder rule the town advanced in prosperity till 1831, when Ibrahim Pasha besieged and reduced the town and destroyed its buildings. On the 4th of November 1840 it was bombarded by the allied British, Austrian and French squadrons, and in the following year restored to Turkish rule.
Battle of Acre.—-The battle of 1189, fought on the ground to the east of Acre, affords a good example of battles of the Crusades. The crusading army under Guy of Lusignan, king of Jerusalem, which was besieging Acre, gave battle on the 4th of October 1189 to the relieving army which Saladin had collected. The Christian army consisted of the feudatories of the kingdom of Jerusalem, numerous small contingents of European crusaders and the military orders, and contingents from Egypt, Turkestan, Syria and Mesopotamia fought under Saladin. The Saracens lay in a semicircle east of the town facing inwards towards Acre. The Christians opposed them with crossbowmen in first line and the heavy cavalry in second. At Arsuf the Christians fought coherently; here the battle began with a disjointed combat between the Templars and Saladin's right wing. The crusaders were so far successful that the enemy had to send up reinforcements from other parts of the field. Thus the steady advance of the Christian centre against Saladin's own corps, in which the crossbows prepared the way for the charge of the men-at-arms, met with no great resistance. But the victors scattered to plunder. Sajadin rallied his men, and, when the Christians began to retire with their booty, let loose his light horse upon them. No connected resistance was offered, and the Turks slaughtered the fugitives until checked by the fresh troops of the Christian right wing. Into this fight Guy's reserve, charged with holding back the Saracens in Acre, was also drawn, and, thus freed, 5000 men sallied out from the town to the northward; uniting with the Saracen right wing, they fell upon the Templars, who suffered severely in their retreat. In the end the crusaders repulsed the relieving army, but only at the cost of 7000 men. (R. A. S. M.)
ACRE, a land measure used by English-speaking races. Derived from the Old Eng. acer and cognate with the Lat. ager, Gr. agros, Sans. ajras, it has retained its original meaning ``open country,'' in such phrases as ``God's acre,'' or a churchyard, ``broad acres,'' &c. As a measure of land, it was first defined as the amount a yoke of oxen could plough in a day; statutory values were enacted in England by acts of Edward I., Edward III., Henry VIII. and George IV., and the Weights and Measures Act 1878 now defines it as containing 4840 sq. yds. In addition to this ``statute'' or ``imperial acre,'' other ``acres'' are still, though rarely, used in Scotland, Ireland, Wales and certain English counties. The Scottish acre contains 6150.4 sq. yds.; the Irish acre 7840 sq. yds.; in Wales, the land measures erw (4320 sq. yds.), stang (3240 sq. yds.) and paladr are called ``acres''; the Leicestershire acre (2308 3/4 sq. yds.), Westmoreland acre (6760 sq. yds.) and Cheshire acre (10,240 sq. yds) are examples of local values.