upe Hidalgo
on the 2d day of February last, between the United States and the
Mexican Republic, and which on the 10th of March last was ratified by
the Senate with amendments.

They were informed that--

This brief statement will indicate to you clearly the line of your duty.
You are not sent to Mexico for the purpose of negotiating any new
treaty, or of changing in any particular the ratified treaty which you
will bear with you. None of the amendments adopted by the Senate can be
rejected or modified except by the authority of that body. Your whole
duty will, then, consist in using every honorable effort to obtain from
the Mexican Government a ratification of the treaty in the form in which
it has been ratified by the Senate, and this with the least practicable
delay. ... For this purpose it may, and most probably will, become
necessary that you should explain to the Mexican minister for foreign
affairs, or to the authorized agents of the Mexican Government, the
reasons which have influenced the Senate in adopting these several
amendments to the treaty. This duty you will perform as much as possible
by personal conferences. Diplomatic notes are to be avoided unless in
case of necessity. These might lead to endless discussions and
indefinite delay. Besides, they could not have any practical result, as
your mission is confined to procuring a ratification from the Mexican
Government of the treaty as it came from the Senate, and does not extend
to the slightest modification in any of its provisions.

The commissioners were sent to Mexico to procure the ratification of
the treaty _as amended by the Senate_. Their instructions confined them
to this point. It was proper that the amendments to the treaty adopted
by the United States should be explained to the Mexican Government, and
explanations were made by the Secretary of State in his letter of the
18th of March, 1848, to the Mexican minister for foreign affairs,
under my direction. This dispatch was communicated to Congress with my
message of the 6th of July last, communicating the treaty of peace,
and published by their order. This dispatch was transmitted by our
commissioners from the City of Mexico to the Mexican Government, then at
Queretaro, on the 17th of April, 1848, and its receipt acknowledged on
the 19th of the same month. During the whole time that the treaty, as
amended, was before the Congress of Mexico these e