Read the excerpt from "Elizabeth Blackwell."

Each night, the sisters worked by lantern light until the stack of completed applications was twenty-nine envelopes high. Together they carried them to the post office, and as the stack was whisked away, Elizabeth squeezed her sister's hand in gratitude.

Which phrase does the author use to help the reader imagine the time period of the setting?

stack was whisked away
completed applications
lantern light
sisters worked