Juliana S. answered 05/04/19
Expert in Adobe Photoshop, Adobe Lightroom, and Photo Retouching
In “Ode to the West Wind,” Shelley connects the wind to inspiration and its power to bring change. Shelley praises nature for its ability to destroy, preserve, and change the world—a concept he uses in “Ozymandias” to show how time and weather have ruined Ozymandias to where “Nothing beside remains. Round the decay / Of that colossal Wreck" (Lines 12-13). The traveler, the tyrant Ozymandias, the artist who made the statue, and the statue itself have all become antiquated.
So, let’s analyze the passage you mentioned on your question:
“Tell that its sculptor well those passions read”
(The sculptor was able to register the tyranny of Ozymandias in the sculpture. In this case, the word “passions” refers to the “frown” and “wrinkled lip, and sneer of cold command” mentioned on the previous lines.)
“Which yet survive, stamped on these lifeless things,”
(The passions or expressions that (which) survive on the “Half sunk,”
“shattered visage”—shattered pieces of the sculpture or “lifeless things.”)
“The hand that mocked them, and the heart that fed;”
(“The hand that mocked them” stands for the sculptor’s work. “Them” refers to “these lifeless things.” “The heart that fed” is Ozymandias himself.)
There should be no “by” in front of “the heart that fed” because the hand and the heart are not from the same characters.