“There was a scientific man who published a book to demonstrate that steam power could never drive a vessel across the Atlantic Ocean, and just as the book got out of the press, a steamer came steaming along at the rate of three hundred miles per day, and others have been at it at the same rate ever since, and the scientific book has gone to the oblivious stream."—[Extract of Col. Ben-ton's letter to C. Street, on the Pacific rail- road, published in the IL National Intelligencer" " It is ass&rted that Dr. Dionysius Lardner, whose fame has extended over the civilized world, demonstrated to a nicety the impossibility of crossing the ocean in a steamer.— His redoubtable arguments and his inevitable conclusions did not, however, prevent the appearance of the English steamer ' Syrius ' at the docks of New York. Practical men with a thousandth part of Dr. Lardner's scientific acquirements were satisfied—the Dr. to the contrary notwithstanding—that there existed no insurmountable impediment; and the consequences we see in the splendid ' lines ' that now cross the ocean with the regularity of ferry-boats."—[Journal of Agriculture, (Boston) for August. [If Col. Benton and the editor of the " Journal of Agriculture" had been careful readers of the " Scientific American," they would not have made the above mistakes, for the Colonel doubtless refers to Dr. Lardner.— He never published a book to demonstrate the impracticability of a steamer crossing the Atlantic Ocean, nor did he ever make an assertion to that effect, it has been attributed to him, and has floated along down time, and through a thousand careless newspapers, but it is not true. On such subjects we regret to say, that we often find many of our leading men very defective in historical knowledge ; they speak ind write in such a manner as would lead us to conclude that they derived the most of their information from unreliable papers. Dr. Lardner distinctly affirmed the very contrary of what has been attributed to him in the two foregoing paragraphs, as any person can find out for himself by consulting pages 295, 6 and 7, of Lardner's work on the "Steam Engine, Navigation, and Railways.”