568 E T H E T H Ethelred as usual did nothing to oppose them, but bought them off with a large sum of money. His efforts at con ciliation were completely successful with Olaf, who, after bein- converted to Christianity, and adopted by Ethelred as his son, remained faithful ever afterwards to his promise of friendship. In the years 997, 998, and 999 the Danes ravaged the coasts of Wessex, Sussex, and Kent. In 1000 Ethelred, energetic at the wrong time and for wrong objects, invaded Normandy, "but suffered a disastrous defeat. He concluded a treaty with that country soon afterwards, and in 1002 married Emma, daughter of Richard duke of Normandy. In the spring a treaty had been concluded with the Danes, but in the winter of the same year, Ethelred suspecting that they were plotting treachery, ordered a general massacre of all the Danes in England. Among others murdered was Gunold, sister of Swend ; and the Danish king, to revenge her death and that of his countrymen, invaded the coast of Devonshire with a large force. He met with scarcely any opposition, and com mitted the usual ravages till 1007, when peace was con cluded by Ethelred s consenting, as at other times, to the payment of a large sum of money. In 1009 Ethelred collected the " largest fleet that had been seen in the reign of any king," but it was soon afterwards nearly wholly destroyed by a violent storm, just bsfore the Danes renewed their invasion. Ethelred, though he had gathered an army, was dissuaded from attacking them by Edric, and afterwards the English, .through the treachery of then- leaders, suffered a series of defeats ; but in 1012 peace was again bought, and Thurkill, one of the Danish leaders, entered the English service. In 1013 Swend, with a more formidable fleet than any he had yet collected, sailed up the Humber, and then marched southward to London ; but meeting there with a strenuous resistance, he was compelled to give up the attack and marched to Bath. Here he was proclaimed king, apparently by the Witan, and with the general consent of the English people, who were doubtless wearied of Ethelred s tncompetency, of the treachery of the nobles, and of the oppressive taxes which had been paid for no purpose. London itself soon acknow ledged the Danish king, and Ethelred, after for a time taking refuge in Thurkill s fleet, escaped to Normandy. Swend died on February 1014, and on his death Ethelred was recalled by the Witan, on the promise of ruling better in future. In the same year he defeated Cnut, son of Swend, but in 1015 Cnut renewed his attack with a large fleet, and being joined by the traitor Edric, ravaged Wessex and Mercia, and was preparing to attack London, when Ethelred died April 23, 101G. (See Palgrave s History of the Anglo-Saxons; Freeman s Norman Conquest, vol. i. ; and Green s History of the English People.} ETHELWULF, or ./ETHELWULF, an Anglo-Saxon king, succeeded his father Egbert about 836. His reign, like that of his father, was almost wholly occupied with wars against the Danish invaders. For a long time he held them in check, and when in 851 they took Canterbury and London, and defeated Beohrtwulf, king of the Mercians, he met them at Ockley in Surrey, and there " made the greatest slaughter among the heathen army that we have heard tell of unto the present clay, and there got the victory." But the Northmen were persevering in their efforts; and it is stated that in 855 they, for the first time, remained over winter in Sheppey. In the same year Ethelwulf made a journey to Rome, accompanied by his youngest and favourite son Alfred, to get the latter consecrated as his successor ; and as his first wife Osburga had been for some time dead, he delayed a few months in France to marry Judith, daughter of the king of the Franks, Ethelbald, his eldest surviving son, indignant at his youngest brother being preferred to him as successor to his father s throne, took advantage of his father s absence to stir up a revolution against him, and obtained the support of so powerful a party that an unnatural civil war was only prevented by Ethelwulf agree ing to grant to his son the government of Wessex, he him self being recognized as over-lord, and retaining the rest of the kingdom. He died in 858, ETHER, (C 2 H 5 ) 2 O, the jEther or ^Ether Sidphuricus of pharmacy, is a colourless, volatile, highly inflammable liquid, of specific gravity - 723, boiling-point when pure 35*6 C, and fusing-point 31 C. It has a strong and characteristic odour, and a hot sweetish taste, is soluble in ten parts of water, and in all proportions in alcohol, and dissolves bromine, iodine, and, in small quantities, sulphur and phosphorus, also the volatile oils, most fatty and resinous substances, gun-cotton (see COLLODION, vol. vi., p. 149), caoutchouc, and certain of the vegetable alkaloids. The vapour mixed with oxygen or air is violently explosive. The making of ether by the action of sulphuric acid on alcohol was known to Raymond Lully, who wrote in the 13th century; and later Basil Valentin and Valerius Cordus described its preparation and properties. The name ether appears to have been applied to the drug only since the times of Froben, who in 1730 termed it spiritus cethereus. Ether is manufactured by the distillation of 5 parts of 90 per cent, alcohol with 9 parts of concentrated sulphuric acid, at a temperature of 140-145 C., a constant stream of alcohol being caused to flow into the mixture during the operation. (See CHEMISTRY, vol. v. p. 5GG). It is purified by treatment with lime and calcium chloride, and subsequent redistillation. According to P. Stefanelli (Ber. deutsch. Chem. Ges., 1875, p. 439), the presence of as small a quantity as 1 per cent, of alcohol may be detected in ether by the colour imparted to it by aniline violet ; if water or acetic acid be present, the ether must be shaken with an hydrous potassium carbonate before the application of the test. Ether when drunk has a rapid though evanescent in toxicating effect, estimated to be more than three times that of the same bulk of whisky, instead of which it is largely consumed in some parts of Ireland. (See H. N. Draper, Med. Press and Circular, iv. 117). Mixed with twice its volume of rectified spirit, it is administered internally as a remedy for nervous headache, flatulence, hiccough, hysteria, and spasmodic vomiting and asthma, occasionally also in angina pectoris, intermittent fevers and typhus, and as an antidote for narcotic poisons, and for relieving the pain caused by biliary calculi. It has been shown by Longet that ether when swallowed even in fatal doses does not at any time produce anaesthesia. Much heat being rendered latent by its evaporation, ether is sometimes employed as a refrigerant in the reduction of hernia. By the use of Dr Richardson s ether spray appa ratus for effecting local anaesthesia, a temperature of - G F. can be obtained. When not allowed to evaporate, ether acts as a rubefacient. Its vapour when inhaled causes at first considerable irritation of the air-passages, and increased rapidity of the pulse, accompanied by much excitement. With the establishment of complete anaesthesia the pulse sinks to G0 or 70. the face becomes pallid, and the muscles are relaxed. Ether occasions more excitement, and requires a somewhat longer period for its exhibition than chloroform, but does not exercise upon the heart the sedative influence of that drug. A history of the employment of ether as an anaesthetic will be found under ANESTHESIA, vol. i. p. 786. See also CHLOROFORM, vol. v. p. G80. ETHER, or /ETHER (aWrjp, probably from aWw, I burn, though Plato in his Cratylus (410, b) derives the name from its perpetual motion on del del TTC/H TOV aepa eW, dei$er;p SiK-aiw? av /caXoiro), a material substance of a more subtle kind than visible bodies, supposed to exist iu those parts of
space which are apparently empty.