A mad-house seems formerly to have been designated a “dark house.” Hence, in “Twelfth Night” (iii. 4), the reason for putting Malvolio into a dark room was, to make him believe that he was mad. In the following act (iv. 2) he says: “Good Sir Topas, do not think I am mad; they have laid me here in hideous darkness;” and further on (v. 1) he asks,
“Why have you suffer’d me to be imprison’d,
Kept in a dark house?”
In “As You Like It” (iii. 2), Rosalind says that “Love is merely a madness, and ... deserves as well a dark-house and a whip as madmen do.”
The expression “horn-mad,” i. e., quite mad, occurs in the “Comedy of Errors” (ii. 1): “Why, mistress, sure my master is horn-mad.” And, again, in “Merry Wives of Windsor” (i. 4), Mistress Quickly says, “If he had found the young man, he would have been horn-mad.”
Madness in cattle was supposed to arise from a distemper in the internal substance of their horns, and furious or mad cattle had their horns bound with straw.
King’s Evil. This was a common name in years gone by for scrofula, because the sovereigns of England were supposed to possess the power of curing it, “without other medicine, save only by handling and prayer.” This custom of “touching for the king’s evil” is alluded to in “Macbeth” (iv. 3), where the following dialogue is introduced:
“Malcolm.Comes the king forth, I pray you?
Doctor. Ay, sir; there are a crew of wretched souls
That stay his cure; their malady convinces
The great assay of art; but, at his touch—
Such sanctity hath heaven given his hand——
They presently amend.
Malcolm.I thank you, doctor.
Macduff. What’s the disease he means?