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466 THE CASKET OF LITERATURE, the car, in which sat the aeronaut, was placed in an horizontal line with the parachute portion of the apparatus. At length, after passing in this appalling manner over Marylebone and Somer's-town, the parachute reached the ground in a field in St. Pancras. Thousands rushed to the spot, where they discovered poor Garnerin lying on his face, in which position he had been thrown by the violence of the shock. On a close examination it was discovered that several cuts were the extent of the injury he had sustained, from which blood flowed in copious streams. He appeared to be greatly agitated on regaining his senses. The circumstance of his having already made several successful descents of course led to the supposition that all was not as it should be with the parachute, and so it turned out. Upon its undergoing a thorough examination, one of the principal strings was found either to have been broken, or to have in some way become perfectly useless, The shape of this parachute was that of the ordinary umbrella. We believe this is the only instance of the descent of a human being by a parachute in this country, previously to the calamitous one we have to describe; and then, as was the case in the previous descents on the continent, the balloon in which the ascent was effected, was, on the parachute being liberated from it, left to 'range its distance.' Consequently, the balloon was manufactured of cheap materials for the occasion. Mr. Cocking, who was a gentleman of considerable scientific attainments, and dedicated a large portion of his leisure to the study of aerostation, connected with which subject his collection of drawings, engravings, models, &c. is most interesting, and perfectly unique, happened to be among those who beheld Garnerin's descent. A casual inspection of the parachute at once showed to Mr. Cocking that, so long as the expansion was to be dependent on the chance of inflation from below, there must necessarily be a risk of its upsetting, and further, that in the event of either of the cords snapping or becoming entangled, the probability would be strongly in favour of a powerful oscillating motion, and a rapid and dangerous descent the result. The consequence was, that when Mr. Cocking determined on using a parachute, he gave a preference to the principle of the one that has turned out so disastrously, which, although generally supposed to be altogether a novelty, was well known to the scientific world, although, on account of certain presumed inherent deficiencies, the practical cultivators of the art did not choose to use it. It was first promulgated in Paris about forty years ago, revived in England by Sir George Cayley, and published by him, with other notices on aerostation, in (we believe) the twenty-fourth volume of Nicholson's Journal. It was subsequently more fully developed and improved upon by Mr. Kerr, by whom it was, in several experiments, publicly illustrated. Its principle consists in an inversion of the preceding ones, in which the surface of least resistance is made to descend foremost. The shape is that of a flattened cone, to the apex of which is attached the car of the adventurer. The chief object of this arrangement is to effect the correction of the oscillatory motion, which to a violent extent usually accompanies the descent, and the insurance of the speedy action of the machine after its detachment. As, however, the principle adopted by Mr. Cocking, and Garnerin's, are both fully explained by a scientific correspondent in No. 26 of The Casket, in an article which we have illustrated with engravings of each plan, we need do no more here than refer our readers to that article. It is due to Mr. Monck Mason, who was one of Mr. Hollond's guests in his great continental balloon excursion, and who has published several papers on the subject of ballooning, to state that he entertained little faith in the plan adopted by Mr. Cocking, and conveyed his opinions on the subject to the editors of some of the daily journals, on the day previous to the experiment. Mr. Mason (and facts now seen to justify his conclusion) considers the oscillations not in any way connected with the form of the parachute. He treats them as the consequence of a first irregularity, impressed upon it by the unequal extension of its parts in the act of opening. As a proof that the aberrations in question are entirely independent of the form of the parachute, or indeed of any other permanent condition of the descent, he observes that the aberrations themselves are by no means permanently or invariably present, at times being much more strongly displayed than at others, occasionally wanting altogether, and almost always becoming fainter as the experiment draws to a close. Mr. Mason, however, saw a much greater objection to the scheme than its mere inadequacy to the saving of the oscillation, in the great sacrifice which it occasions in the resisting powers of the parachute, 'to an extent, indeed, which (we now quote from Mr. Mason) gives us reason to entertain much apprehension concerning the issue of the experiment by which it is now about to be illustrated. By a course of calculations, unnecessary to be inserted here, we learn that the resistance exerted upon the base of a cone in passing through the air (supposing it a plane) is to that upon its oblique presentation in the proportion of unity to the sine of half the vertical angle. Supposing the apex of the cone, in the present instance, to be a right angle (from which, we believe, it is a little removed), this proportion would stand in numbers, "as one is to one divided by the square root of two" (algebraic expressions a vetitum nefas in the public prints); consequently, the loss of resistance occasioned by presenting such a cone point foremost, is equal to one-third of what it would have been had the base been so disposed as to encounter the action of the air. Owing to this circumstance, the power of the projected parachute, assuming its radius to be 17 feet, would only avail to retand the fall of the individual in the same degree as an ordinary parachute whose radius was 14 feet. Now, the descending velocity of such a parachute, charged with a weight of 484 pounds (that of the whole apparatus, including the aeronaut himself, his ballast, and other equipments), we ascertain from Dr. Hutton's theorem, would be exactly 20 1/2 feet per second, and the force developed, the same as if the individual had fallen unprotectedly from an altitude of six feet and a half; very nearly twice as much as in these cases is generally considered to be the acme of human bearing.' Whether the loss of Mr. Cocking is the result of the accuracy of the above theory, and his ignorance of it, or of the insufficient strength of his machine, is a point that may now perhaps never be determined. But we were present during the whole of the preparations to the time of the ascent, and certainly had a strong feeling of the fragileness of the machine. We know that the upper hoop, from which the canvass depended, and on which the great strain must have been, was first made of copper, which utterly collapsed on its strength being tested; and, although the hoop of block tin, which was afterwards substituted, stood the tests that had been too much for the copper one, we are fully prepared for hearing that the pressure of the air, combined with the weight of the parachute and its contents, exceeded anything that had been calculated on, and operated in the same way on the tin as the pressure of weight alone had previously done on the copper hoop. It was suggested to Mr. Cocking to have a hoop of ashwood, the material used for the hoops of balloons, but he declined it, on account of its increased weight. We may as well observe in this place that he had tried experimental descents with a model from the Monument, which had been so perfectly satisfactory, that he never wavered in his confidence of success. Mr. Cocking had for years contemplated a descent with a parachute, but till the building of the great Vauxhall balloon by Mr. Charles Green, there was neither a machine of sufficient capabilities as regards power to carry up so large an additional weight, nor an aeronaut who was inclined to hazard the experiment of so suddenly releasing his balloon from a burden amounting to nearly 500lbs. The consequence of the instantaneous removal of so large a weight may in some degree be imagined upon its being stated that it is no uncommon thing for the balloon, when a few handsful of sand are thrown over, to obtain an additional elevation of 300 or 400 feet, and instances have occurred when, on two or three bags of 14lbs. each being emptied of their contents, the machine has shot up from 800 to 1,200 feet. The progress of the united machines was watched therefore with a double interest on this occasion. The main difficulty Mr. Green anticipated was that of breathing immediately after the severance of the balloon and parachute; because then, in order to counteract the immense rising power the balloon would acquire on being relieved of the parachute, he would be obliged to throw open the escape valve as widely as possible, which would have the effect of bringing him and his companion into an atmosphere of gas, as the balloon would continue to rise faster than the gas would disperse. To meet this difficulty, he took with him a silk bag filled with common air, having two mouth-pieces, one to be used by himself and