Permit me to express to you all the gratitude I feel for the interest you take in my young travelling companion. Mr. Ward is worthy of it, alike from his youth, his courage, and his devotion to science. Mr. Epaminondas has just communicated to me your generous intentions towards myself, and your purpose of sending a steamer to Manaos to take the place of the Piraja, and facilitate our exploration of the Rio Negro and the Rio Madeira. I do not know how to thank you enough; all that I can say is, that this favor will allow me to make an exploration of these rivers which would be otherwise impossible. If the result of these researches be as favorable as my hopes, the honor will be due, in the first instance, to the liberality of the Brazilian government. Encouraged by the results thus far obtained, I think that, if the circumstances are favorable, on arriving at Tabatinga, we shall make a push into the lower part of Peru, while my companions will explore the rivers intermediate between this town and Teffé; so that we shall probably not return to Manaos before the end of October. Accept, my dear Sir, the assurance of my high regard, &c., &c. L. AGASSIZ. Footnote 61: Some English travellers have criticised the position of the town, and regretted that it is not placed lower down, at the immediate junction of the Rio Negro with the Solimoens. But its actual situation is much better, on account of the more quiet port, removed as it is from the violent currents caused by the meeting of the two rivers.—L. A. Footnote 62: When this was written there was hardly any prospect of the early opening of the Amazons to the free commerce of the world. The circumstance that since the 7th of September last this great fresh-water ocean has been made free to the mercantile shipping of all nations will, no doubt, immensely accelerate the development of civilization in these desert regions. No act could have exhibited more unequivocally the liberal policy which actuates the Brazilian government than this. To complete the great work, two things are still wanting,—a direct high road between the upper tributaries of the Rio Madeira and Rio Paraguay, and the abolition of the subsidies granted to privileged companies, that the colossal traffic of which the whole basin is susceptible may truly be thrown open to a fair competition.—L. A. Footnote 63: _Senahor Pimenta Bueno._