Whereas by an act of Congress of the United States of the 24th of May,
1828, entitled "An act in addition to an act entitled 'An act concerning
discriminating duties of tonnage and impost,' and to equalize the duties
on Prussian vessels and their cargoes," it is provided that upon
satisfactory evidence being given to the President of the United States
by the government of any foreign nation that no discriminating duties of
tonnage or impost are imposed or levied in the ports of the said nation
upon vessels wholly belonging to citizens of the United States, or upon
the produce, manufactures, or merchandise imported in the same from the
United States or from any foreign country, the President is thereby
authorized to issue his proclamation declaring that the foreign
discriminating duties of tonnage and impost within the United States are
and shall be suspended and discontinued so far as respects the vessels
of the said foreign nation and the produce, manufactures, or merchandise
imported into the United States in the same from the said foreign nation
or from any other foreign country, the said suspension to take effect
from the time of such notification being given to the President of the
United States and to continue so long as the reciprocal exemption of
vessels belonging to citizens of the United States and their cargoes,
as aforesaid, shall be continued, and no longer; and

Whereas satisfactory evidence has lately been received from the
Government of His Holiness the Pope, through an official communication
addressed by Cardinal Antonelli, his secretary of state, to the minister
resident of the United States at Rome, under date of the 7th day of
December, 1857, that no discriminating duties of tonnage or impost are
imposed or levied in the ports of the Pontifical States upon vessels
wholly belonging to citizens of the United States, or upon the produce,
manufactures, or merchandise imported in the same from the United States
or from any foreign country: