But where unbruisèd youth with unstuffed brain
Doth couch his limbs, there golden sleep doth reign."
Shakespeare describes, too, with lifelike fidelity, the causes of insomnia, which are not weariness or physical pain, but undue mental anxiety. He constantly contrasts the troubled sleep of those burdened with anxieties and cares, with the happy lot of the laborer whose physical weariness insures him a tranquil night's repose. Henry VI. says:—
"And to conclude, the shepherd's homely curds,
His cold thin drink out of his leather bottle,
His wonted sleep under a fresh tree's shade,
All which secure and sweetly he enjoys,
Are far beyond a prince's delicates."
And Henry V. says:—
"'Tis not the balm, the sceptre and the ball,