Of particular note are Storer's mentions of his ship's encounters with other vessels believed to be engaging in the slave trade. Storer's letter of May 27, 1848, instructs the commander of the U.S. steamer Allegheny to follow a ship suspected of carrying enslaved Africans: "...the Barque 'Louisa'... cleared this day for the coast of Africa with a cargo consisting of various articles, and in sufficient quantities, to be deemed suspicious." In a letter and order dated September 5, 1848, Storer spells out the problem in clear language to John A. Davis, the commander of the U.S.S. Perry: "I have reasons for believing that vessels engaged in the slave trade under the American flag, sometimes land their cargos on the coast between Cape Frio and the latitude of St. Salvadore. You will therefore cruise with the U.S. Brig Perry under your command along that part of the coast outside the Abrolhos Banks for two weeks, keeping a good look out for suspicious looking vessels under American Colors...." He then relates specific instructions for search and seizure of such vessels, careful to make sure that such activities do not violate the jurisdiction of Brazil. Storer tells Davis to "use every effort to arrest, bring to well merited punishment all persons who on the open seas may disgrace the American flag by making it in any way subservient to the pursuit and protection of this most nefarious commerce."

The front flyleaf contains the ownership inscription of David Tod, U.S. Ambassador when the Brazilian-American Claims Treaty was signed on January 27, 1849. The inscription reads: "David Tod, esquire / Envoy Extraordinary / and Minister Plenipotentiary / of the United States / Rio de Janeiro." Indeed, David Tod was the American representative who signed the claims document along with the Emperor of Brazil. The United States received 530,000 milreis to cover indemnifications against American interests which in dollar equivalents of 1850 was over one million dollars at the time. This ledger was likely used as evidence and then returned to Storer.

While the entries are not in complete chronological order, the letter book contains an index towards the end.