If you look at anything Wallace Stevens ever wrote, you will see that this is his favorite mode - write something fraught with meaning but open enough to allow multiple readings. I love Stevens for this, and in fact I've written several different perspectives on his "Anecdote of the Jar" and "The Emperor of Ice Cream," all of which are "correct" according to a close reading of the poem. However, in a persuasive essay, a writer MUST pick a stance and stick with it. To turn an essay in that says "This poem is about making you think" would result in a great big C from almost any instructor.
This is a reversal of the usual method of etching, where the lines of the design are exposed to the acid, and the plate printed by the intaglio method. Relief etching (which Blake referred to as " stereotype " in The Ghost of Abel ) was intended as a means for producing his illuminated books more quickly than via intaglio. Stereotype, a process invented in 1725, consisted of making a metal cast from a wood engraving, but Blake's innovation was, as described above, very different. The pages printed from these plates were hand-coloured in water colours and stitched together to form a volume. Blake used illuminated printing for most of his well-known works, including Songs of Innocence and of Experience , The Book of Thel , The Marriage of Heaven and Hell and Jerusalem .