578 A L K A L L forming deep purple solutions, from which acids precipitate in orange-coloured flakes. Alizarin has the atomic com position C i4 H 8 O 4 , and has recently been made synthetically from the hydrocarbon C 14 H 10 called anthracene, which occurs among the products of the destructive distillation of coal. This is the first example of the artificial forma tion of a natural colouring matter. For further details see CHEMISTRY. ALKALI, a term originally applied to the ashes of plants, now employed in inorganic chemistry as a generic name given to the group of compounds that have the pro perty of neutralising acids. The use of the term is, however, generally confined to such members of the group as are soluble in water. The most soluble alkaline bodies are the oxides of potassium (potash), sodium (soda), lithium (lithia), and ammonium (aqueous ammonia); and next in order the oxides of calcium (lime), barium (baryta), and strontium (strontia). The solutions of these bodies exert a caustic or corrosive action on vegetable and animal sub stances, and precipitate the oxides of the heavy metals from solutions of their salts. Many vegetable colouring matters are changed in tint by alkaline solutions for instance, reddened litmus becomes blue, yellow turmeric brown, and syrup of violets and infusions of red cabbage green. ALKALOIDS, the name of a group of organic bodies that possess alkaline properties. They are characterised by the property of combining with acids to form salts, and many have the power of giving an alkaline reaction with vege table colours. All the natural alkaloids contain nitrogen as an essential constituent, and they are especially marked by possessing great medicinal power. Many artificial alkaloids have been made of recent years in which phos phorus, arsenic, and antimony occupy the place of nitrogen. For the individual properties, tests, &c., of different alka loids, see CHEMISTRY. ALKANET (Alkanna tinctoria, or Anchusa tinctoria), a plant of the order Eoraginacece, indigenous to the south of France and the shores of the Levant. It is extensively cultivated on the Continent for the sake of the root, which yields a fine colouring matter, imparting a beautiful car mine tint to oils, wines, wax, and all unctuous substances. Being perfectly harmless, alkanet is much used for colour ing in pharmacy. Some of the mixtures styled port wine owe their colour to this dye, and it is also employed in staining furniture. AL-KINDI, ABU YUSUF, etc., styled by pre-eminence " The Philosopher of the Arabs," flourished during the first half of the 10th century, and died at some unknown date posterior to 961. His literary activity was encyclopaedic, and spread itself over all the sciences* The titles of his works number nearly 200 in the catalogue of Casiri, and amount to 265 in that of Flligel ; but the latter appears in some cases to have enumerated the same works under two divisions, and it is doubtful whether the philosopher has not been confounded with another writer of the same name. His treatises are arranged under the following heads, which throw some light on his classification of the sciences : Philosophy in general, logic, politics, ethics, arithmetic (under which he discusses the unity of God), spherology, theory of music (which was closely connected with all primitive speculation from its religious character), astronomy, meteorology, geo metry, cosmology (the form, <fcc., of the heavens), astrology, medicine, and on various arts, besides his commentaries and controversial writings. Of all these, none except some treatises on medicine and astrology remain. Others of them must have been known in the Middle Ages, for Al-Kindi is placed by Roger Bacon, along with Alhazen, in the first rank after Ptolemy as a writer on perspective (optics). Some of them were certainly translated by Gerard of Cremona. Whatever his influence may have been on the Schoolmen, he was undoubtedly a great initiator as regards his countrymen. He was one of the earliest translators and commentators of Aristotle, but he appears to have been, like Al-Farabi, superseded by Avicenna. He marks the first philosophic revolt against Islamism, and his doctrine on the simplicity and unity of the Deity was apparently equally Aristotelian and un-Mahometan. See Fliigel, Abhandhmgen fur die Kunde des Morgen- landes, erster Band, 1859.) ALKMAAR, a town of the Netherlands, in the province of North Holland, situated on the Helder canal and on the railway between Haarlem and the Helder, about 20 miles N.N.W. of Amsterdam. The streets of Alkmaar are extremely neat and regular, and are intersected by canals lined with trees, while the ramparts of the town have been converted into beautiful boulevards. Many of the public buildings are elegant, especially the church of St Lawrence, a Gothic edifice of the 15th century. Alk maar is the seat of a court of primary jurisdiction and of a tribunal of commerce, and possesses good schools as well as several literary and scientific societies. Its principal article of commerce is cheese, for which it is said to be the chief market in the kingdom, if not in the world. Besides cheese, it has a good trade in butter, corn, and cattle, and manufactures of salt, sailcloth, soap, vinegar, and leather. Alkmaar successfully sustained a siege by the Duke of Alba in 1573, and in 1799 gave its name to a convention signed by the Duke of York and the French general Brune, in accordance with w T hich the Russo-British army evacuated Holland. Population, 12,000. ALKMAAR, HEINRIK VON, the German translator of the celebrated satirical poem Reineke de Vos, flourished in the latter half of the 15th century. In the preface to his work, which is the only source of information as to his life, he states that he was tutor to the Duke of Lorraine, and that he translated the poem from the Walsch. In spite of the latter statement, many have attributed the authorship to him ; but it is now knoAvn that the story had a much earlier origin. Some have supposed the name Alkmaar to be a pseudonym. ALL-SAINTS DAY, ALL-HALLOWS, or HALLOWMAS, a festival, first instituted about 610 A.D., on the 1st of May, in memory of the martyrs, and celebrated since 834 on the 1st of November, as a general commemoration of all the saints. As the number of sauits increased, it became im possible to dedicate a feast-day to each. Hence it was found expedient to have an annual aggregate commemora tion of such as had not special days for themselves. The festival is common to the Roman Catholic, English, and Lutheran churches. See BELTANE. ALLAH, the Arabic name for the one true God which is employed in the Koran, and has been adopted into the language of all Mahometan nations. It is compounded of al, the definite article, and ilah, meaning worthy to be adored. See MAHOMETANISM. ALLAHABAD, a division, district, and city of British India, under the jurisdiction of the lieutenant-governor of the North- Western Provinces. The ALLAHABAD DIVISION comprises the six districts of Allahabad, Cawnpur, Fathi- pur, Hamirpur, Banda, and Jaunpur. It is bounded on the north and east by the Etawah and Farrakhdbad districts and the province of Oudh; on the south by the Benares division and the Rewah state; and on the west by the states of Bandelkhand and the Jhansi division. Total population (1872), 5,466,116. ALLAHABAD DISTRICT lies between 24 49 and 25 44 N. lat, and between 81 14 and 82 26 E. long. In shape the district is that of an irregular oblong; and it is diffi cult accurately to describe its boundaries, as at one extre
mity it wanders into Oudh, while on the south the villages
