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supporters of the fire balloons had asserted their superiority, but the ardour of MM. Roberts and Charles, the conductors of the former experiment with hydrogen, continued unabated. A violent contest arose between the partisans of the Montgolferian mode of inflation and those who preferred hydrogen gas; and the opponents of the former method determined to bring the affair to a practical test. Accordingly, Messrs. Roberts and Charles volunteered to ascend in a balloon constructed after their own directions. The machine used on this occasion was formed of gores of silk fastened together, forming a globe 27 feet in diameter; the whole being covered with a varnish of caoutchouc. A net was spread over the upper hemisphere, and fastened to a hoop which passed round the middle of the balloon. To this a sort of car was suspended a few feet below the under part of the balloon; and, in order to prevent the bursting of the machine, à valve was constructed, by the opening of which some of the inflammable air might be occasionally let out. The gas having been supplied, the aeronauts took their seats at two o'clock, on the afternoon of the 1st December, 1783, and immediately the balloon was released from its fastenings, and rose majestically in the atmosphere. They continued above the earth for nearly two hours, at the expiration of which time they alighted at a distance of 27 miles from Paris. As the balloon still retained a great quantity of gas, M. Charles determined to take another voyage by himself; M. Roberts accordingly got out of the car, and as the machine was now lighter by about 130 lbs., it arose with such velocity, that in a few minutes the aeronaut discovered by the barometer that he had attained a height of 9,000 feet. During this second voyage a most magnificent scene presented itself. Rising from the valley where the balloon had descended, and leaving the evening mists and gloom far beneath him, he appeared to have entered the domain of some Eastern enchanter. All terrestial objects had disappeared from his view the luminary which had cheered him on his previous excursion, but which had set below the horizon before he had re-ascended, against burst on his enraptured sight with all the richness of an autumnal sunset. Vast masses of vapour rolled beneath his feet, and as the billows of cloud appeared to mount over and over each other, the different tints which they displayed gradually became more diffused, until the last ray of the sun disappearing, rendered the whole one vacillating sea of uniform obscurity; the only object exhibiting the effect of the sun's light being the machine in which the spectator was seated; even this, elevated as it was, in a few seconds became deprived of the immediate influence of the sun's rays. M. Charles beheld a second sunset; and the moon, which had by this time attained some height in the heavens, now shed a flood of pure cold light on the aërostat and the sea of vapour over which it floated.

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Recollecting, however, his promise to return to his friends in half an hour, the adventurer opened the valve, and having suffered the gas gradually to escape, he calmly descended about three miles distant from the place whence he had departed. By the calculations made he appears to have ascended in this voyage to a height of 10,500 feet, somewhat higher than the summit of Mount Etna.

This voyage established the superiority of the hydrogen balloon; and in the many remarkable excursions which have since been made, we do not find the Montgolfier or fire-balloon to have been employed.

Many improvements have since been effected in balloons, and a vast number of plans, good, bad, and indifferent, proposed for rendering the science of aerostation more perfect. In the infancy of balloons a plan was suggested, and tried by M. Garnerin, a celebrated aëronaut, for preventing the unpleasant concussion of the car of the balloon on descending to the ground. This was to be effected by means of a parachute, a machine somewhat in the form of an umbrella: it was formed of canvas of about 30 feet in diameter, made to fall in folds around a long tin tube, but capable of being expanded. To this tube, and, by means of ropes, to the edges of the canvas, a wicker basket was attached in which M. Garnerin placed himself. This machine was conpected with the balloon above by a rope passing through the tin tube, so

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that by severing the rope, the aeronaut could disengage the parachute and basket from the balloon, and the machine in falling downwards would, it was supposed, be opened by the resistance of the air, and would then descend gently, and without rebounding from the ground. At six o'clock on the afternoon of the 21st September, 1802, the balloon, with the parachute, and M. Garnerin hanging to it, ascended from North Audley-street, amidst the acclamations of innumerable spectators. The weather was exceedingly beautiful, and a light breeze carried the balloon to the north-east. In about eight minutes the aerostat had ascended to an immense height, and M. Garnerin conceived it to be a favourable opportunity to cut the rope, which he accordingly effected, and in an instant he was separated from the balloon, trusting his safety to the parachute. At first, namely before the parachute opened, he fell with great velocity, but as soon as it was expanded, which took place in a few moments, the descent became very gentle and gradual, but accompanied by a vibratory motion, which sometimes nearly threw the aëronaut out of his basket. This instrument, however, failed with respect to the purpose for which it was designed, for on coming to the ground it rebounded considerably, giving M. Garnerin some pretty severe shocks; he, however, fortunately sustained no material injury in the experiment, although his spirits were rather discomposed. A descent has lately been effected by means of a parachute, with more success than attended the exploit of M. Garnerin. On the occasion of a balloon ascent at the Surrey Zoological Gardens on the 10th of May, in the present year Mrs. Graham, the aeronaute, took up with her in a parachute, a monkey; having attained a sufficient height, she cut the rope, and the machine descended with great ease to the ground. The "imitation of a man" experienced no ill effects from the ascension which he repeated on the following day.

Many attempts have been made to progress through the atmosphere by means of wings placed in the car of the balloon, but none of them have succeeded in the least degree, and it would therefore be useless to give a description of any of the instruments contrived for this purpose.

Since the introduction of carburetted hydrogen gas for lighting cities, it has quite superseded the use of pure hydrogen gas for the purpose of inflating aërostatic machines, both on account of its superior cheapness, and the ease with which it may be cbtained. Although not so light as the pure hydrogen, it is sufficiently buoyant to raise a balloon in the air beyond the reach of human vision; and as aëronauts find thousands of persons willing to pay for witnessing a balloon-ascent, the exhibition has of late years become a highly lucrative profession; for a balloon may be filled by any of the gascompanies with carburetted hydrogen, for about 51. or 10l.; and, as many as 5,000 persons, each paying one shilling, may be assembled " in the season to witness the ascent.

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To cause his balloon to descend the aeronaut is obliged to allow the gas to escape; and if he does not alight near a gas manufactory, it is difficult for him to re-ascend, should he wish it, without much delay. As this will prove a considerable drawback to the success of an itinerant aëronaut, and will be likely to retard the prosecution of aërostation as a commercial speculation, to which this science, (which was to open a new field for research in Natural Philosophy, but which has proved of little utility,) has now, or shortly will become, exclusively confined; we think we may recommend, as it has been represented to us, the use of a gas for the inflation of balloons hitherto unemployed, which will render the operations of ascent and descent easy and expeditious.

Ammoniacal gas is the substance we allude to. It is easily and cheaply procured from bones and other animal substances: its specific gravity is only about one-thirtieth more than that of light carburetted hydrogen; and it possesses the property of being absorbed by water to an immense extent; so much so, that a pint of cold water will absorb nearly 700 pints of this gas, which will be again given out upon the application of a slight degree of heat. The consideration of these qualities will shew of what great utility this gas might prove on aërial excursions. A balloon filled with it would carry nearly

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as great a weight as if inflated with carburetted hydrogen. A communication, capable of being closed with a stop-cock, might be made between the interior of the balloon and a vessel of cold water in the car then, on opening this communication, and, by means of a syringe, throwing the water into the balloon, a considerable quantity of gas would be absorbed; and the specific gravity of the whole being thus increased, the machine would begin to descend. The water, after this operation, having fallen into the receptacle in the car, the mere application of a small fire, or even a lamp, would cause the ammoniacal gas to be evolved, which, rising into the interior, would render the balloon capable of re-ascending

Our correspondent in suggesting to us this plan, also favoured us with a statement of the comparative weights, and ascensive powers of balloons filled with different gases; shewing the ease with which this new project could be carried into execution. From this we shall extract the following passage:- "The balloon may be supposed to contain 50,000 cubic feet. This quantity of air would weigh 4,650 pounds. The same volume of hydrogen would weigh 318 pounds; of light carburetted hydrogen 2,610 pounds; and a like quantity of ammoniacal gas 2,730 lbs. Then, supposing the balloon and apparatus to weigh 1,000 lbs., it would, if filled with, hydrogen, have an ascensive power of 3,332 pounds, being the difference between the weight of the machine and contents, and that of 50,000 cubic feet of air. On the same principle, if inflated with carburetted hydrogen, the power of ascension would be equal to 1,040 lbs.; and if with ammonia, it would rise with a power of 920 lbs. Then the extra apparatus for the ammoniacal balloon, (including water, fuel, &c.) would probably weigh 800 lbs.; which would leave an ascens ive power (sufficient for all ordinary voyages,) of 120 pounds, and the quantity of water required to absorb this, and cause the descent, would only occupy a space of three cubic feet."

With this we shall conclude our notice of the science of Aerostation; a science which, although it might appear destined for higher purposes, has yet only ministered to the wonder of the multitude, and the pockets of its professors. If this "child" is really to become a "man," as Dr. Franklin predicted, it is either very backward in its growth, or its manly qualities are not so fully developed as that philosopher imagined they would be.

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THE WALL OF SEVERUS." And this then is the Roman wall," he said, scrambling up to a height which commanded the course of that celebrated work of antiquity;" What a people! whose labours, even at this extremity of their empire, comprehended such space, and were executed upon a scale of such grandeur! In future ages, when the science of war shall have changed, how few traces will exist of the labours of Vauban and Coehorn, while this wonderful people's remains will even then continue to interest and astonish posterity! Their fortifications, their aqueducts, their theatres, their fountains, all their public works, bear the grave, solid, and majestic character of their language; and our modern labours, like our modern tongues, seem but constructed out of their fragments."-Sir Walter Scott.

"We are not made of wood or stone, and the things which connect themselves with our hearts and habits cannot, like bark or lichen, be rent away without our missing them."-Sir Walter Scott.

223

EXCHANGE NO ROBBERY.

It was during the period when St. Domingo was a flourishing French colony, that a vessel from Bordeaux was about setting sail from the island upon her homeward voyage.

The name of the ship was the "Faustina," and she is reported to have been of great burthen, and remarkable for fast-sailing, and was moreover acknowledged to be a very active traveller, having taken soundings in every bay of the Indian coast, and the inspection of her red and brilliant copper sheathing, was sufficient to prove that neither barnacles nor weeds, which are in the habit of attaching themselves to sluggish wanderers of the deep, had been able to produce any effect upon her indefatigable keel.

The captain was what is commonly termed a sea wolf. His country was the ocean; the waves had cradled him in his infancy; his limbs had become strong amidst the sea breezes, and he roamed throughout the waters free and unconfined as the fish that dwell therein. His destiny could award him, to a certainty, no other death than that arising from shipwreck. It may, therefore, be easily imagined that he detested dry ground as an alderman hates water; and a lengthened stay upon shore would, in all probability, have caused him land sickness, in the same manner as sea sickness overpowers the unlucky wight who trespasses upon the domains of father Neptune. As a necessary consequence, neither ship nor captain liked repose. Neither the mind nor the body of which the man and the machine might be said to be jointly formed could become habituated to the quiet of harbour or anchorage; both required an extensive field of operation: an operation always new, always receding; in short, that drama of a life of alternatives between the acts of which arise frequent intervals of serenity and of danger, leading both man and vessel to an unknown and unexpected termination. Hence it may easily be inferred, that the stay of the “Faustina," in foreign and homeward ports, was never of greater duration than was absolutely necessary.

At the time of which we are writing every thing was in readiness for getting under weigh, and the moment was approaching in which, all sail being set, the impatient captain was to take his final leave, when a boat heavily laden was seen slowly advancing from the shore towards the Faustina, whose flag was already hoisted, and whose long pennant was twisting and flapping at the mast-head, like the whip of a postillion about to start.

The signals made by the boatmen left no doubt as to their destination, and the importance of so tardy a visit; the Bordeaux captain was therefore obliged to repress his impatience, and await the result.

After tugging long and with difficulty, owing to the heavy loading of the boat, they at length came alongside. The ship's company then perceived that it contained eight or ten large cases of solid construction, marked, numbered, and packed with all possible care, forming a shipment despatched by a religious brotherhood long established in the colony, consigned to a community of monks of the same order at Bordeaux, and recommended to the especial care of the captain by the head of the fraternity, under engagement to pay a handsome rate of freight. The cases were brought on board, and their contents were stated by the agents of the monks to consist of the bones of holy brothers, who had died in the colony, martyrs to their zeal for the propagation of the gospel among the natives. These sacred remains were addressed to the general of the order, for the purpose of receiving in their native land those funeral rites and honours which were due to relics so holy and so precious.

Although somewhat surprised at this strange statement, the captain took charge of the boxes, ordered them to be stowed away, and delivered a re

ceipt to the agent. In commercial parlance such a receipt is called a bill of lading; it declares the nature of the shipment, as made by the shipper, and the captain usually places the words "contents unknown," before his signature of the document. Upon arrival of the merchandize at the port of destination it is delivered to the consignee, upon the production of the bill of lading, which is usually forwarded to him by another channel, and if the articles are found conformable thereto, and in good order, the receipt is given up, and the transaction ends. The captain, therefore, signed as having received on board a certain number of cases stated to contain bones or relics, but adding in the usual form, " contents unknown."

The ship set sail, and the boxes were soon forgotten like any other part of the cargo; but on reaching the middle of the voyage, which was not accomplished without difficulty, owing to the tempestuous weather that prevailed, the Faustina experienced some derangement of her stowage, and as changes had to be made with respect to such portion of the cargo as was near at hand, the captain was obliged to remove the packages belonging to the brotherhood. The heavy nature of the cases, and the great disproportion between their weight and their declared contents, gave rise to reflections in the mind of the captain which had not occurred to him in the confusion attendant upon his departure from St. Domingo, and the hurry which prevailed during the shipment; but the reiterated recommendations of the ghostly agent, and the extreme importance which, unconsciously perhaps to himself, had marked his proceedings, created from that moment a thousand suspicions, of which our navigator felt strongly disposed to ascertain the reality. The devil was no doubt at his elbow, for now he could no longer resist his desire to ascertain the contents of the mysterious packages, and he yielded to the temptation. He called a council of his followers, and by the help of good tools an opening was made in the solid joints of the cases which did not yield without an obstinate resistance to these efforts of curiosity; but what was the surprise of the captain and his friends when, instead of thigh bones, toe joints, and skulls, the cases were found to contain splendid church ornaments, valuable plate, consisting of candlesticks, crosses, lamps, chalices and other articles adorned with precious stones; besides entire bars of gold, evidently melted down from ornaments out of use; and lastly, several cases entirely filled with dollars and other coins. The captain, be it remembered, was a shrewd fellow, and well acquainted with monks and missals. At the sight of so much wealth an idea crossed his brain, whereat, it may be supposed, that Satan chuckled with glee, and which we shall proceed to detail. Meantime the cases were nailed up, and a place allotted for them much more secure than that which they had previously occupied, the vessel continuing her course.

On the approach of the Faustina to the European coast, the captain had no difficulty in finding a plausible pretext for running into a port of Spain. The bad weather that prevailed during the voyage had caused some damage, which the captain declared must of necessity be remedied before he could expect to reach his destination; no observation was therefore elicited from the ship's company in consequence of this determination. Upon putting into port the cases were landed with other goods, with which, for a while, they remained intermixed. A pretended examination, and subsequent repair of the vessel took place, and during this operation the valuable contents of the cases were exchanged, and rendered conformable to the declaration in the bill of lading. The immense wealth they had previously contained was placed in safe hands, and the vessel again set sail for Bordeaux. It is not, perhaps, necessary to state, that a share of the spoil, proportionate to the value of the secret, was guaranteed to the performers who took part in this drama.

The Faustina at length reached Bordeaux. As soon as her arrival was known, the holy brotherhood, corresponding with that of St. Domingo, assembled in solemn conclave. The consignment had, no doubt, been long looked for by the expectant friars, and the news of the apparent consummation of their hopes filled their minds with a pure and holy joy. A procession

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