WASHINGTON, _June 11, 1858_.
_To the Senate of the United States_:
In answer to the resolution of the Senate of the 19th ultimo, respecting
the Isthmus of Tehuantepec, I transmit herewith a report from the
Secretary of State, with the documents by which it is accompanied,
together with the copy of a letter from the Postmaster-General of the
21st ultimo to the Department of State.