Scorn not the Sonnet; Critic, you have frowned,  
Mindless of its just honours; with this key  
Shakspeare unlocked his heart; the melody  
Of this small lute gave ease to Petrarch's wound;  
A thousand times this pipe did Tasso sound;  
With it Camoens soothed an exile's grief;  
The Sonnet glittered a gay myrtle leaf  
Amid the cypress with which Dante crowned  
His visionary brow: a glow-worm lamp,  
It cheered mild Spenser, called from Faery-land  
To struggle through dark ways; and when a damp  
Fell round the path of Milton, in his hand  
The Thing became a trumpet; whence he blew  
Soul-animating strains--alas, too few!
William Wordsworth
http://www.poemhunter.com/poem/scorn-not-the-sonnet/