Sound and Sense

True ease in writing comes from art, not chance,
As those move easiest who have learned to dance.
'Tis not enough no harshness gives offense,
The sound must seem an echo to the sense:
Soft is the strain when Zephyr gently blows,
And the smooth stream in smoother numbers flows;
But when loud surges lash the sounding shore,
The hoarse, rough verse should like the torrent roar;
When Ajax strives some rock's vast weight to throw,
The line too labors, and the words move slow;
Not so, when swift Camilla scours the plain,
Flies o'er the unbending corn, and skims along the main.
Hear how Timotheus' varied lays surprise,
And bid alternate passions fall and rise!