Conversation so far:
What conspiracy was Mary Surratt involved in?
On December 23, 1864, Dr. Samuel Mudd introduced Mary Surratt's son John Surratt, Jr. to John Wilkes Booth. Booth recruited John Jr. into his conspiracy to kidnap Lincoln.
Did Mary Surratt have co-conspirators?
As part of the plot to kidnap Abraham Lincoln in March 1865, John, Atzerodt, and Herold hid two Spencer carbines, ammunition, and other supplies at the Surratt tavern in Surrattsville.
Did Mary Surratt help Booth?
Shortly before leaving Washington to kill Lincoln, John Wilkes Booth spoke with Mary Surratt and handed her a package.
What was in the package that John Wilkes Booth gave to Mary Surratt?
The package John Wilkes Booth handed Mary Surratt contained binoculars.

Question: what were the binoculars for
Self-contained rewrite: What were the binoculars that John Wilkes Booth gave to Mary Surratt for?