It is but fitting that I should express here my thanks to Captain Faria for the courteous manner in which he accomplished the task assigned him by the government. He was not only a most hospitable host on board his vessel, but he allowed me to encumber his deck with all kinds of scientific apparatus, and gave me very efficient assistance in collecting.—L. A. Footnote 91: PARÁ, February 23, 1866. SIRE:—On arriving at Pará in the beginning of this month, I had the pleasure to find your Majesty’s kind letter, which had been awaiting me for several days. I ought to have acknowledged it immediately, but I was not in a condition to do so, being overcome by fatigue. It is only during the last two or three days that I begin once more to occupy myself as usual. I confess that nothing but the presentiment of regrets which would have pursued me to the end of my days has prevented me from returning directly to the United States. Even now I find it difficult to take up the most simple occupations. And yet I am not ill; I am only exhausted by incessant work, and by the contemplation, each day more vivid and impressive, of the grandeur and beauty of this tropical nature. I need to look for a time upon the sombre and monotonous aspect of a pine forest. How good you are, Sire, to think of me in the midst of the vital affairs which absorb your attention, and how considerate are your acts! The New Year’s present you announce enchants me.[93] The prospect of being able to add some comparisons of the fishes from the basin of the Uruguay to such as I have already made between the Amazonian species and those of the rivers on the eastern coast of Brazil has a special attraction for me. It will be the first step towards a knowledge of the types of the temperate zone in South America. I wait with increasing impatience for the moment when I shall be able to examine them. In the mean while allow me to give you a rapid sketch of the results thus far obtained in my voyage on the Amazons.