Pythagoras also recognized the potency of music as a remedial force. Tuneful strains were believed by the physicians of old to be uncongenial to the spirits of sickness; but among medicine-men of many American Indian tribes, harsh discordant sounds and doleful chants have long been a favorite means of driving away these same spirits.[178:3] Aulus Gellius, the Roman writer of the second century, in his "Attic Nights,"[178:4] mentioned a traditionary belief that sciatica might be relieved by the soft notes of a flute-player, and quoted the Greek philosopher Democritus (born about B. C. 480) as authority for the statement that the same remedy had power to heal wounds inflicted by venomous serpents. According to Theophrastus, a disciple of Plato and Aristotle (B. C. 374-286), gout could be cured by playing a flute over the affected limb;[179:1] and the Latin author Martianus Capella, who flourished about A. D. 490, asserted that music had been successfully employed in the treatment of fevers, and in quieting the turbulence of drunken revellers. Among the ancient northern peoples, also, songs and runes were reckoned powerful agents for working good or evil, and were available "to heal or make sick, bind up wounds, stanch blood, alleviate pain, or lull to sleep."[179:2] A verse of an old Icelandic poem, called the "Havamal," whose authorship is accredited to Wodan, runs as follows: "I am possessed of songs, such as neither the spouse of a king nor any son of man can repeat. One of them is called, 'the Helper.' It will help thee at thy need, in sickness, grief, and all adversities. I know a song which the sons of men ought to sing, if they would become skilful physicians."[179:3] The Anglo-Saxons appreciated the healthful influence of music. At a very early period in their history, a considerable number of persons adopted music and singing as a profession. It was the gleemen's duty to entertain royal personages and the members of their courts. Afterwards these functions devolved upon the minstrels, a class of musicians who wandered from castle to camp, entertaining the nobility and gentry with their songs and accompaniments. The intermediate class of musicians, whom the later minstrels succeeded, appeared in France during the eighth century, and came, at the time of the Norman Conquest, to England, where they were assimilated with the Anglo-Saxon gleemen.[180:1] In the early poetry of Scandinavia there is frequent reference to the magical influence of music. Wild animals are fascinated by the sound of a harp, and vegetation is quickened. The knight, though grave and silent, is attracted, and even though inclined to stay away, cannot restrain his horse.[180:2] The earliest biblical mention of music as a healing power occurs in Samuel, XVI, 23, where David (the son of Jesse, the Bethlehemite) cured the melancholy of King Saul by playing upon the harp. "So Saul was refreshed, and was well, and the evil spirit departed from him."