The poem reads like a tiny lab report that slowly turns strange. The speaker calls it "an experiment," and the experiment is oddly playful: two people, "hands talking," seem to use gesture, maybe sign language or shadow play, to frighten a bear "back into a book." The wild animal becomes something that can be shooed into a story, as if fear can be handled by language and imagination.
Then the mood shifts. "Bills of mortality" were the old lists of deaths in a parish or city, and the speaker says they seem "full / of pure hunger." That suggests the bear was never only a storybook creature. Hunger, the thing that drives it, also runs through the record of human deaths.
The speaker's feelings are hard to pin down, but the tone feels calm, curious, and a little uneasy. The title, "Abstract," fits: the poem sums up a big idea in a few lines. We can push danger into a book for a moment, but hunger remains real.