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[[start page]] [ 11 ] frame, that forms the upper part of the vehicle in which I mean to perform my Aerial Voyage. It will be furnished likewise with wings and oars; the use of the former is to excite air when the globe is becalmed, and thereby to move it horizontally: they have the form of large rackets, and are covered with a loose flounces of oiled silk. The oars which differ from the wings only in size, will be worked with a vertical Motion, and are intended to effect a depression of the machine; by which I hope to be enabled either to check its ascension, or to descend without the necessity of letting out the inflammable air. I exhibit these, not only as matters of curiosity to persons who have not seen or understood the French experiments; but to point out to those who have, the peculiar object of my enterprize. For I have the ambition to be the first, not only to visit the English atmosphere, but to ascertain the practicability of rendering the Balloon stationary, or descending at pleasure by means of oars, acting vertically; and superceding the use and necessity of valves. In this only circumstance I aim to deviate into originality, from the splendid and successful track of the French philosophers. There are two methods of filling a Balloon for ascension; and it is remarkable, that the method first discovered and executed by Messrs. Montgolfier, is the most hazardous and difficult to apply to use. It is effected, as a chimney is heated, by a common fire; and a Balloon of this kind is a moving chimney, closed at the top, made of light materials and raised by the elasticity which is always given to air by fire. This requires a constant application of fire to the contents of the Balloon, which is a difficult operation and C2 [[end page]] [[start page]] [ 12 ] the least error in the application may be the occasion of consuming the apparatus, and endangering the lives of those who trust to it. I have chosen inflammable rather then elastic air for my guide. It is a substance produced by the action of vitriolic acid on metals or semi-metals, and is familiar to that vapour which takes fire in mines, and carries terror and destruction wherever it approaches. This you will say is changing one hazardous instrument for another, but the chances of setting fire to the elastic Balloon, or of not applying the heat so equally as to answer the purposes of ascension, are numerous ; those of exploding an inflammable Balloon, arise only from thunder clouds ; and if proper attention be paid to the weather, they arenot numerous or difficult to be avoided : besides, inflammable air being seven times lighter than atmospherical air, and rarified air not more than three times lighter, the Machine must of course be proportionable larger in the use of the latter than in that of the former. My design to use inflammable air, has been the occasion of my acquaintance with Doctor George Fordyce, a physician of eminance, a lecturer in chemistry, and probably the first chemist in the island. I consider this as a very fortunate circumstance ; for besides the improvement and satisfaction I derive from his friendship, he has offered in the kindest manner to fill the Balloon, in a method which is an improvement on that of the French philosophers, as he contrives the tubes for conveying the inflammabe so as to prevent the admission of any atmospheric aid. He is also of opinion, that air produced by the vitriolic acid and zinc alone, is the lightest of any that has been yet used. [[end page]] [[start page]] [ 13 ] But, in the leading incidents of this era of my life, I must reckon among the happiest, my introduction to Mr. Biggin, a young gentleman, distinguished by his birth, education, and fortune ; of improved and elegant accomplishments, a strong lover of science, and of a liberal and affectionate heart. This young gentleman, in the first days of our acquaintance, expressed a wish to accompany me in my ascent. And as the regions I intended to visit are unknown, and Mr. Biggin's talents so useful and engaging, I have accepted his offer. The voyage will, by this circumstance, be rendered more interesting, we shall direct our particular attention to different objects ; and in any of those incidents which novelty may render astonishing, we shall communicate and multiply our joy, or lessen and remove our apprehensions. I am, Sir, with great regard, your much obliged, and most hunble servant, Vincent Lunardi London, August 2, 1784 [[end page]] [[start page]] [ 14 ] Letter III. My Dear Friend, The events of this extraordinary island, are as variable as its climate. You here experience the extremes of elevation and dejection, as you do of heat and cold in a shorter time, and in a greater number of occurrences, than in any country I know in the world. When I wrote you last, every thing relative to my undertaking wore a favourable and pleasing appearance. I am at this moment overwhelmed with anxiety, vexation and despair. On advertising my intention to go up with my Balloon, it was natural to suppose that any latent ambition of the same kind would show itself, and perhaps spring forward to seize the applause attending the execution of such an enterprize. I do not say, that this would not have dissappointed me ; but it would not have left me in any situation of distress like the present. A Frenchman whose name is Moret ; and who may possibly have assisted at some trials at Paris to launch Balloons in the manner of Montgolfier, advertised as it were in competition with me; and fixed on a day for ascending with his Balloon, previous to that, on which I had the permission of Sir George Howard to make my excursion from Chelsea-Hospital. To hasten my own undertaking would have been entering into a ridiculous race with Moret; and if I had been inclined to such a measure, it was probable, that the appointed [[end page]]
