Byron's Corsair sells 10,000 copies on first day of publication, 1814

By those, that deepest feel, Is ill exprest
The indistinctness of the suffering breast;
Where thousand thoughts begin to end in one,
Which seeks from all the refuge found in none;
No words suffice the secret soul to show,
For Truth denies all eloquence to Woe.
On Conrad's stricken soul exhaustion prest,
And stupor almost lull'd it into rest;
So feeble now - his mother's softness crept
To those wild eyes, which like an infant's wept:
It was the very weakness of his brain,
Which thus confess'd without relieving pain.
None saw his trickling tears - perchance if seen,
That useless flood of grief had never been:
Nor long they flow'd - he dried them to
In helpless -hopeless - brokenness of heart:
The sun goes forth, but Conrad's day is dim;
And the night cometh - ne'er to pass from him.
There is no darkness like the cloud of mind,
On Grief's vain eye - the blindest of the blind!
Which may not - dare not see but turns aside
To blackest shade - nor will endure a guide!

canto 3 verse 22