ALCORAN ALDER. 



91 



;>f liquids, is by weighing them in a delicate balance 

 against an equal volume of pure water, of a similar 

 temperature. Alcohol is extremely inflammable, 

 and burns with a pale-blue flame, scarcely visible in 

 bright day light. It occasions no fuliginous deposi- 

 tion upon substances held over it, and the products 

 >f its combustion are carbonic acid and water, the 

 veight of the water considerably exceeding that of 

 the alcohol consumed. According to Saussure, jun. 

 100 parts of alcohol afford, when burned, 136 parts 

 of water. The steady and uniform heat, which it 

 gives during combustion, makes it a valuable material 

 tor lamps. The action between alcohol and some 

 of the metals, particularly platinum, is remarkable. 

 When a small piece of thin platinum leaf, suspended 

 liy a wire, is heated by a spirit lamp, and then 

 quickly put into a glass, in which there is a little 

 alcohol, so that it sliall remain just over the surface, 

 and of course in the vapour arising from the alcohol, 

 it continues red-hot, as long as there is any fluid in 

 the jar ; which is owing to the vapour undergoing a 

 sort of combustion, and generating heat sufficient to 

 keep the metal in that state. This action affords 

 the means of making a lamp without flame. There 

 are some substances which communicate colour to 

 the flame of alcohol ; from boracic acid, it acquires a 

 greenish-yellow tint ; nitre and the soluble salts of 

 baryta cause it to burn yellow, and those of strontia 

 give it a beautiful rose colour; cupreous salts im- 

 part a fine green tinge. Alcohol dissolves pure soda 

 and potassa, but it does not act upon their carbo- 

 nates ; consequently, if the latter be mixed with alco- 

 hol containing water, the liquor separates into two 

 portions, the upper being alcohol deprived, to a con- 

 siderable extent, of water, and the lower the aqueous 

 solution of the carbonate. The alcoholic solution of 

 caustic potassa was known in old pharmacy under 

 the name of Fan Helmonfs tincture of tartar. It 

 is used for purifying potassa. Alcohol dissolves the 

 greater number of the acids. It absorbs many gas- 

 eous bodies. It dissolves the vegetable acids, the 

 volatile oils, the resins, tan, and extractive matter, 

 and many of the soaps ; the greater number of the 

 fixed oils are taken up by it in small quantities only, 

 but some are dissolved largely. The composition of 

 alcohol was investigated by Saussure, and Gay Lus- 

 sac. The result was, that 100 parts of pure alcohol 

 consist of 



Hydrogen . . . 13-70} 

 Carbon .... 51-98 V 100-00. 

 Oxygen .... 34-32) 

 These numbers approach to 3 proportionals of hy- 

 drogen, =. 3 ; 2 of carbon, = 12 ; and 1 of oxygen, 

 = 8. Or it may be regarded as composed of 

 1 volume carbureted hydrogen, and I volume of the 

 \ apour of water ; the 2 volumes being condensed into 

 1, the specific gravity of the vapour of alcohol, com- 

 pared with common air, will be 1-599, or, according 

 to Gay Lussac, 1-013. When alcohol is submitted 

 to distillation with certain acids, a peculiar compound 

 is formed, called ether (q. \.), the different ethers 

 being distinguished by the names of the acids em- 

 ployed in their preparation. 



ALCORAN. See Koran. 



ALCUINUS, or ALBINCS, Flaccus; an English- 

 man, renowned, in his age, for learning; the confi- 

 dant, instructor, and adviser of Charlemagne. He 

 was born in York (according to some, near London) 

 in 732, was educated under the care of the venerable 

 Bede and bishop Egbert, and was made abbot of 

 Canterbury. Charlemagne l>ecame acquainted with 

 him in Parma, on his return from Rome, whence he 

 had brought the pallium for a friend ; invited him, 

 in 782, to his court, and made use of his services in 

 his endeavours to civilize his subjects. In the royal 



academy, he was called Flaccus Albinus. To secure 

 the benefit of his instructions, Charlemagne estab- 

 lished at his court a school, called Palatina, and in- 

 trusted him with the superintendence of several 

 monasteries, in which A. exerted himself to diffuse 

 a knowledge of the sciences. Most of the schools in 

 France were either founded or improved by him ; 

 thus lie founded the school in the abbey of St Mar- 

 tin of Tours, in 796, after the plan of the school in 

 York. He himself instructed a large number of 

 scholars in this school, who afterwards spread the 

 light of learning through the empire of the Franks. 

 A. took his leave of the court in 801, and retired to 

 the abbey of St Martin of Tours, but kept up a con- 

 stant correspondence with Charles to the time of his 

 death, in 804. He left, besides many theological 

 writings, several elementary works in the branches 

 of philosophy, rhetoric, and philology ; also poems, 

 and a large number of letters, the style of which, 

 however, is not pleasing, and plainly betrays the un- 

 cultivated character of the age ; nevertheless, he is 

 acknowledged as the most learned and polished man 

 of his time. He understood Latin, Greek, and He- 

 brew. His works appeared in Paris, 1617, folio, 

 and in a more complete form in Ratisbon, 1777, 

 2 vols. folio. 



ALDEBARAN, or the bull's eye, in astronomy ; a 

 star of the first magnitude in the southern eye of the 

 constellation Taurus. 



ALDEGONDE, St Philip, of Marnix, lord of mount 

 St Aldegonde, was born in Brussels, 1538, and 

 studied in Geneva. He drew up, in the beginning 

 of Dec. 1565, the act of compromise for the preser- 

 vation of the privileges of the Netherlands, which 

 was signed by count Louis of Nassau, Henry of Bre- 

 derode, and himself. The act was directed chiefly 

 against the introduction of the inquisition into the 

 Netherlands, and the members promised to assist 

 each other with their persons and property. It was 

 rejected, however, by the regent Margaret. In 

 1566, Alva arrived. St A. fled, with the friends 

 of the prince of Orange, to Germany, and returned 

 with them as their leading counsellor. In 1573, he 

 fell into the hands of the Spaniards, at Maesluys, 

 was afterwards exchanged, and conducted many di- 

 plomatic negotiations of the young republic abroad. 

 He defended Antwerp a long time, though not suc- 

 cessfully. He assisted in establishing the university 

 of Leyden, and died there, professor of theology, in 

 1598. 



ALDENHOVEN, battle at, March 1, 1793. The en- 

 gagement near this town, situated between Juliers 

 and Aix la Chapelle, opened the campaign of 1793. 

 The year previous, the Austrians had been obliged, 

 after the battle of Jemappe, to evacuate Belgium, 

 and retire behind the Roer. Dumouriez, at the be- 

 ginning of the year 1793, threatened Holland with 

 an invasion. To prevent this, and to raise the siege 

 of Maestricht, the prince of Coburg drew together 

 his army, consisting of 40,000 men, behind the Roer, 

 and forded this river, March 1, in two columns, at 

 Duren and Juliers. In the engagement which en- 

 sued, the French lost about 6000 men killed and 

 wounded, and 4000 prisoners. On the following 

 day, Aix la Cliapelle and Liege were occupied, the 

 siege of Maestricht raised, and the French actively 

 pursued. At Neerwinden the French halted, and 

 received a re-enforcement, consisting of the corps 

 destined to invade Holland, but were beaten here, 

 March 18, a second time. 



ALDER. The alder or owler (betula alnus) is a 

 tree which grows in wet situations, and is distinguish- 

 ed by its flower-stalks being branched, its leaves be- 

 ing roundish, waved, serrated, and downy at the 

 branching of the veins beneath. It is common in 



