I was sorry that the shortness of my stay prevented my accepting an invitation from Mr. and Mrs. Agassiz. They are persons of whom it is impossible to know a little without wishing to know a great deal more. They had lately returned from their explorations in Brazil, but more especially in the Valley of the Amazon. The popular narrative of the expedition (for it was composed of several persons) was written by Mrs. Agassiz, and has just been published. The more detailed and scientific account, by Mr. Agassiz, is eagerly expected. His character appears to be a most singularly transparent one. He has strong social instincts. In society he is evidently in his true element. But all the while, by the side of this keen enjoyment of society, you see that his soul has been constructed for making those discoveries in physical science, and acquiring those new ideas, he has so much happiness in presenting to the minds of others. His rich genial conversation and ready sympathies are worthy of the high position he holds in the scientific world. To Mr. Thomas G. Appleton—the first American, I believe, who crossed the Atlantic in his own yacht—I am indebted for several kindnesses; among them for his taking me to his brother-in-law, Mr. Longfellow, who resides at Cambridge, about three miles from Boston. Mr. Longfellow’s house is the oldest in the place, and has a good deal of curious antique carving and panelling. This is as it should be, for one can hardly imagine a poet living in a new, square-built, brick house, without a tradition or association. [Sidenote: _Young Ladies’ Recitations._]