The choice of a subject has already been spoken of as a matter of importance, and a word should be said touching its manner of treatment. This introduces a discussion of the kind of lecture which at the present time is mainly in demand. Many wise and good men have questioned the character of the popular lecture. In their view, it does not add sufficiently to the stock of popular knowledge. The results are not solid and tangible. They would prefer scientific, or historical, or philosophical discourses. This conviction is so strong with these men, and the men themselves are so much respected, that the people are inclined to coincide with them in the matter of theory, while at the same time they refuse to give their theory practical entertainment. One reason why scientific and historical lectures are not popular is to be found in the difficulty of obtaining lecturers who have sufficient ingenuity and enthusiasm to make such lectures interesting. The number of men in the United States who can make such lectures attractive to popular audiences can be counted on the fingers of a single hand. We have had but one universally popular lecturer on astronomy in twenty years, and he is now numbered among the precious sacrifices of the war. There is only one entirely acceptable popular lecturer on the natural sciences in New England; and what is he among so many? But this class of lectures has not been widely successful, even under the most favorable circumstances, and with the very best lecturers; and it is to be observed, that they grow less successful with the increasing intelligence of the people. In this fact is to be found an entirely rational and competent explanation of their failure. The schools have done so much toward popularizing science, and the circulating-library has rendered so familiar the prominent facts of history, that men and women do not go to the lecture to learn, and, as far as any appreciably practical benefit is concerned, do not need to go. It is only when some eminent enthusiast in these walks of learning consents to address them that they come out, and then it is rather to place themselves under the influence of his personality than to acquire the knowledge which he dispenses. Facts, if they are identified in any special way with the experience and life of the lecturer, are always acceptable; but facts which are recorded in books find a poor market in the popular lecture-room. Thus, while purely historical and scientific lectures are entirely neglected, narratives of personal travel, which, combine much of historical and scientific interest, have been quite popular, and, indeed, have been the specialties of more than one of the most popular of American lecturers, whose names will be suggested at once by this statement.