obtained of ten or eleven degrees, showing an independent motion through the air of 5 to 71⁄2 miles an hour, produced by the machinery. The descent was made safely about 90 miles from Paris. As a matter of fact, M. Dupuy de Lôme does not seem to have accomplished much beyond what M. Giffard had done previously: and it is to be regretted that both M. Giffard and he should have left the subject where it is; but fortunately, guided by the data obtained, we may form an idea, much more satisfactory than heretofore, of the position of the question, and of the prospects of the invention for the future. In the first place, the possibility of constructing, on principles analogous to those of aquatic navigation, a buoyant aerial screw ship, which shall have a form of small resistance, which shall be stable and easy to manage, and which shall obey her rudder, has been fully established; there only remain the questions what power is necessary to give such a vessel a certain speed through the air; what amount of power can be carried; and how that power may be applied. The relation between power and speed has been carefully investigated by M. de Lôme on sound mechanical principles, checked by the actual data of aquatic navigation, and although their application to this problem is new, they seem to have been confirmed by experiment so far as the limited trial extended. M. de Lôme calculated beforehand that to give a speed of five miles an hour would require a net expenditure of about 3ths of a horse-power;* for which, allowing for loss, he allotted 4 men, or ths of a horse-power. In the actual experiment he found that 8 men (or ths of a horse-power net) gave 6.4 miles per hour, which is sufficient confirmation, the power varying, according to a well-known rule, as the cube of the speed. Hence to give 10 miles an hour would require 2 horse-power, 20 miles 20 horse-power, and so on. The form of power adopted by M. de Lôme, namely human effort, involved an enormous waste of weight; and in reasoning on what may be done, we have a right to assume a more *The power required to propel the balloon depends largely on the value of the coefficient representing the reduction of resistance due to the form or to the lines of the vessel. There is little experience of this for the air, but M. de Lôme asserts by the analogy of ships, that it may be as low as or even Allowing for resistances of the car and net, and for other defects, he has in his calculations brought it out at a mean value of; and adopting this, we have the following formula. If d = largest diameter of balloon in feet, and v = velocity through the air in miles per hour, then the net horse-power required will be in round numbers H. P. = d2 v3 1,000,000 economical economical arrangement. A horse-power in the shape of 10 men, with a relay of 5, weighs above a ton; but in the steam engine this may be reduced very largely. Mr. Giffard's engine and boiler weighed 112 lbs. per horse-power; in some boats lately working on the Thames* the weight was only 60 or 70 lbs., and in other instances it has been reduced still lower. 6 To keep up the power, we may estimate that the engine will require, per horse-power per hour, 3 to 5 lbs. of fuel and 25 to 28 lbs. of water. But, by an ingenious air surface condenser," lately introduced by Mr. Perkins, the water evaporated may be recovered and used over again, and M. Giffard has pointed out that the fuel and water lost would take the place of the ballast usually put in the car. We should be quite within actual practice in estimating for each horse-power, 100 lbs. weight of engine, boiler, and condenser, and 10 lbs. for each hour's consumption. Hence, as M. de Lôme's balloon had, after allowing for his entire apparatus and machinery, about 4600 lbs. disposable buoyancy, we find he could carry a 20-horse engine, and keep up a speed of 20 miles an hour for 13 hours. By enlarging the balloon, say to 100 feet diameter, we should get an available buoyancy of 20 tons, which would enable a speed of 20 miles an hour to be kept up for 24 hours, and still leave some 7 or 8 tons free. These calculations are formed, be it observed, on data already existing; we have made no allowance for the improvements that would naturally arise when the attention of ingenious men was drawn to the subject, and when actual experience had been gained. The application of high power would doubtless require many alterations in construction, and much study of detail, and there is every probability that in the course of this study by skilful engineers such ameliorations would be brought about as would result in the attainment of higher speeds than we have above taken credit for. Let us only, for the sake of argument, assume that we could attain for our balloons an independent velocity of 25 miles an hour through the air; it is worth while to inquire what that would do towards the solution of the great problem of aerial locomotion. According We have here to consider the effect of the wind. to the best tables, what may be called an ordinary breeze blows between ten and twenty miles an hour, a strong breeze between *Trans. Inst. of Naval Architects,' 1872, p. 269. Paper by Mr. F. J. Bramwell, F.R.S. twenty twenty and thirty, a high wind between thirty and forty, and a gale up to fifty or more. The average velocity of balloons carried along by the wind has been found to be about twentyfive miles an hour, and we may fairly assume that the current is as often below as above this velocity. Hence it follows that for half the days in the year we might have the power, by properly constructed dirigible balloons, of navigating the air as we pleased, in any direction. If the wind were for us, we should make thirty to fifty miles an hour; if against us, we should go slowly, but, as the French sailor said, 'Please God, we should certainly arrive.' In the other half of the year, when the wind exceeded the velocity we could command, we must give up the idea of steaming against it; but even then our steering power would give us very great advantage in deviating from the wind's direction. An example will make this clear. Suppose that a high wind were blowing from the west, with a velocity of forty miles an hour (the highest, perhaps, that it would be prudent to attempt a voyage with), we could not go anywhere westerly, or even due north or south, but, by the aid of our independent speed of twenty-five miles, we could command any course we pleased between north-east and south-east, giving us still a very large and useful range; and what we lost in this respect we should gain in swiftness, as our velocity running east would be sixty-five miles an hour. Then one most important use of dirigibility would be in facilitating the descent, and in avoiding the many dangers to which the aeronaut, in his present helpless position, is so often exposed. He could choose his place of landing with precision, bearing right or left at pleasure, and, turning his head to the wind, he could get rid of, or largely diminish, the dragging which is so dangerous, and which has so often brought a fatal termination to balloon voyages. Indeed, with ordinary precautions in the construction and management of the apparatus, a dirigible balloon would furnish one of the safest, as well as one of the swiftest and pleasantest, modes of locomotion. And, further, it must be borne in mind that the increased frequency of balloon voyages would lead to a more careful practical study of the atmospheric conditions bearing on them. We may, indeed, conclude that the future use of balloons will probably depend on a moderate steering facility, combined with the power of taking advantage of the best circumstances of wind and weather; and we do not doubt that with such a combination, well studied, and wrought out with the skill of which the present age is capable, the balloon has the power to become a really useful machine. We We have had no space in this article to speak of flying. There are many students of aerial locomotion who profess a contempt for the balloon, as a mere plaything, and consider that the only proper solution of the problem is by a flying machine, which shall sustain itself in the air, like a bird, by mechanical means. They disdain floating power, which, they say, birds do not possess, and which is, therefore, unnecessary. It would be just as reasonable to propose, on analogous grounds, to abolish boats and substitute swimming-machines. The plus lourd que l'air' doctrine is a delusion, founded on the mechanical blunder of confounding gravity and momentum, which are two distinct things. It is a more reasonable objection that a balloon, from its large size, must offer a great resistance to the air at high speeds, but this resistance has been enormously overrated,* and it is a cheap price at which to acquire the fulfilment of the first condition of aerial locomotion-that of overcoming the action of gravity. At all events, a dirigible balloon is a thing actually in existence; a flying-machine is, at present, only an idea. ART. V.-1. Galerie Historique du Théâtre Français. Par Mazurier. Paris, 1810. 2. Mémoires de Mile. Clairon. Écrits par elle-même. Paris, 1822. 3. Études sur l'Art Théatral; suivies d'anecdotes inédites sur Talma. Par Madame Veuve Talma: née Vanhove, maintenant Comtesse de Chalot. Paris, 1836. 4. Le Théâtre Français sous Louis XIV. Par Eugène Despois. Paris, 1874. 5. Histoire du Romantisme. Théophile Gautier. Paris, 1874. 6. Foyers et Coulisses; Histoire anecdotique de tous les Théâtres de Paris: Comédie Française. Paris, 1874. N the eventful year of 1871, an interest hitherto unknown Drama. When civil broils followed the withdrawal of the German army which had invested Paris, a small section of the Comédie Française took refuge in London at the Theatre of the Opéra Comique in the Strand, and remained there from the beginning of May till the end of July. These artists were but fifteen in number; only one or two among them had ever left * The resistance to M. de Lôme's balloon, of 122,000 cubic feet, at 5 miles an hour, was only 211⁄2 lbs. ; at 20 miles an hour, it would be 344 lbs. France France before or could say so much as half-a-dozen words in Few people in London knew anything about them. These exiled comedians, unused to the arts of advertisement, and accustomed to general recognition in their native city, played for some time in London to empty houses. Resorting to no art but that of their own acting, they trusted to its excellence and to that of the authors they represented - Molière, Marivaux, Regnard, Alfred de Musset, Dumas, père, Augier, Feuillet; and by degrees they succeeded so well that it became difficult to obtain places even at the highest prices. This small gallant company forwarded welcome remittances to the rest of the troupe left under severe pressure in Paris. us. The farewell banquet given at the Crystal Palace to the Comédie Française, and many other marks of consideration bestowed upon its members in England, are gratefully remembered by them now, and afforded them as much happiness as it was possible for them to experience during their residence among But they were beset with daily anxieties: fire, famine, and slaughter reigned in the city of their affections; and they went to rest each night dreading the news which the morning might bring. It was on their return from a brief day of enjoyment at Windsor that they were startled by the sight of placards posted up all over London which proclaimed 'Paris in flames.' With a load of misery and anxiety at heart they gave some of their most charming representations. The fire which destroyed the Tuileries and the Palais Royal threatened, by its close proximity, the theatre containing those collected treasures of time which no display of modern wealth can ever replace. The Théâtre Français, however, survived this peril, as it had done many others; and when the favourites of its company returned upon the defeat of the Commune to tell of the welcome they had won in the metropolis of England, they found their beautiful temple still standing, and their public again longing for their performances. But another danger was impending. The heavy exactions of the German conquerors left France so much impoverished that its Government intimated to the subsidized theatres the possibility of a total withdrawal of further assistance in money. Had such a measure been adopted, the Théâtre Français must ultimately have lost its high place in the dominion of art; it must have gradually assumed the conditions which attach to a playhouse existing as a mere money speculation. The aid of national funds for its maintenance has made it what it is; and without the continuance of such assistance it could not retain its position |