Again, the contagiousness of pestilence is thus alluded to by Beatrice in "Much Ado About Nothing" (i. 1): "O Lord, he will hang upon him like a disease: he is sooner caught than the pestilence, and the taker runs presently mad." The belief, too, that the poison of pestilence dwells in the air, is spoken of in "Timon of Athens" (iv. 3):
"When Jove Will o'er some high-viced city hang his poison In the sick air."
It is alluded to, also, in "Twelfth Night" (i. 1), where the Duke says:
"O, when mine eyes did see Olivia first, Methought she purged the air of pestilence."
While on this subject, we may quote the following dialogue from the same play (ii. 3), which, as Dr. Bucknill[610] remarks, "involves the idea that contagion is bound up with something appealing to the sense of smell, a mellifluous voice being miscalled contagious; unless one could apply one organ to the functions of another, and thus admit contagion, not through its usual portal, the nose:"
"_Sir Andrew._ A mellifluous voice, as I am true knight.
_Sir Andrew._ Very sweet and contagious, i' faith.
_Sir Toby._ To hear by the nose, it is dulcet in contagion."
[610] "Medical Knowledge of Shakespeare," p. 121.
_Insanity._ That is a common idea that the symptoms of madness are increased by the full moon. Shakespeare mentions this popular fallacy in "Othello" (v. 2), where he tells us that the moon makes men insane when she comes nearer the earth than she was wont.[611]
Music as a cure for madness is, perhaps, referred to in "King Lear" (iv. 7), where the physician of the king says: "Louder the music there."[612] Mr. Singer, however, has this note: "Shakespeare considered soft music favorable to sleep. Lear, we may suppose, had been thus composed to rest; and now the physician desires louder music to be played, for the purpose of waking him."
[612] Halliwell-Phillipps's "Handbook Index to Shakespeare" (1866), p. 333.
So, in "Richard II." (v. 5), the king says:
"This music mads me: let it sound no more; For though it have holp madmen to their wits, In me, it seems, it will make wise men mad."
The power of music as a medical agency has been recognized from the earliest times, and in mental cases has often been highly efficacious.[613] Referring to music as inducing sleep, we may quote the touching passage in "2 Henry IV." (iv. 5), where the king says: