As to horizontal speed, perhaps the fastest time on record was made by Garnerin and Snowdon, from London to Colchester, some eighty miles, in one hour, or about 110 feet per second, almost swifter than an eagle flies; and another balloon went from Paris across the Alps, to the vicinity of Rome, in twenty-two hours, making over fifty miles per hour, considering its zig-zag travel. The reason for such great speed is, that the different air currents travel far faster in the upper regions than below, where the velocity of the wind is seldom over twenty miles per hour; and yet, were it not for the continually changing scenery, the æronaut would imagine himself stationary. The shortest trip, perhaps, in the annals of this art, both as to hight and distance, was made, a few years ago, by a gymnast, at Woodward's Gardens, that most beautiful pleasure resort in this city. The little disobliging monster went lazily, and with great difficulty, over the fence and capsized promptly on the other side, leaving the trapeze-man hanging, by the seat of his unmentionables, on the top of it in an uncomfortable position, but no bones were broken. V.--ABSENCE OF DANGER. It is erroneous to suppose that ærial voyages are fraught with even ordinary danger; on the contrary, travel by sea and land is far more so; for, although thousands of assensions have been made, but very few persons have met with accidents, in fact, a less number by far comparatively, than by any other profession or mode of locomotion; and, whenever such has happened, gross carelessness or ignorance was often the cause. During the late Franco-German war, over sixty balloons, many but indifferently constructed, left Paris, during the siege, with some one hundred and eighty persons and nearly three millions of letters. All reached a point of safety. Professor Wise, the most noted American æronaut, has made, during the last forty years, nearly five hundred voyages, and one in particular, in 1859, of nearly 1200 miles--perhaps the longest on record--with three companions, from St. Louis, Mo., to New York State. This trip was made partly in the midst of a tornado, while above Lake Erie, during which time some twenty sailing crafts succumbed to the effects of the storm, yet the intrepid æronauts alighted in safety. M. Green, who was the first to use coal gas, instead of pure hydrogen, and has also made hundreds of successful ascensions, was carried from London to Weilburg, in the central part of Germany, about seven hundred miles in eight hours, without the slightest mishap. Lastly, Arban, crossed the Alps from Marseilles to Turin, four hundred miles, in stormy weather during the night. Mont Blanc to the left, on a level with the top of which he was, resembled an immense block of crystal--sparkling with a thousand fires; while the moon occasionally seemed to have borrowed the light of the sun. VI.--CHARM OF ÆRIAL TRAVEL.