In one class of essay Mark Twain is past master, the essay of travel. In “A Tramp Abroad” and “Following the Equator,” not to speak of that satire on foolish American tourists, “Innocents Abroad,” we have not only some of the best of Mark Twain’s writing, but examples of a kind of essay in which very few authors have succeeded. The traveler who can see things with his own eye and make the reader see them, with a tramp’s independence of what guide books, geographies, and histories say, is the rarest of companions. A good essay in travel looks easy when it is done, but is very seldom met with because the independent eye is so seldom placed in a human head. Moreover, until recent times of cheap transit, most men of letters have been obliged to stay at home and make literature of domestic materials or what the great world sent them in books. Though literature of travel is very old, going back to the time when the first educated man visited a neighboring tribe and lived to return home and tell the tale, yet the personal essay of travel is, in its abundance, the product of the nineteenth century, when authors ceased to be poor and could circumnavigate the globe. The English historian, Kinglake, is remembered not for his “Crimean War” but for his “Eothen,” published in 1844. It was so strange and fresh a book of travel that several London publishers rejected it. An account of a journey in the East that omitted information about many great landmarks of Palestine and had not a word of statistics--how could a publisher recommend it to the British people? One secret of the book is that Kinglake, having tried to write his travels in various forms and having failed, hit on the plan of addressing his account to a friend, and the feeling of freedom which this gave him prevented him, he says, “from robing my thoughts in the grave and decorous style which I should have maintained if I had professed to lecture to the public. Whilst I feigned to myself that you, and only you, were listening, I could not by any possibility speak very solemnly. Heaven forbid that I should talk to my genial friend as though he were a great and enlightened Community, or any other respectable Aggregate.” Thus it came about that Kinglake, aiming at one friend, reached the community, the “Aggregate,” and found in it a host of friends. In the same year that saw the publication of “Eothen,” Thackeray began his “Journey from Cornhill to Cairo,” another book of travel that stands like a green tree in a world of guide posts. Among American writers, besides Mark Twain, who have made delightful books of their journeys abroad, are Aldrich, Howells, and Charles Dudley Warner.