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[385]
Vol. LVI. The London Chronicle. No. 4364.
From TUESDAY, October 19, to THURSDAY, October 21, 1784.
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^[[See other Side. - handwritten in ink]]
To the PRINTER of the LONDON CHRONICLE.
  SIR,
As balloons are now the current subject of discussion, give me leave to enter a little into the merits of them; for all that has hitherto been done, amounts to no more than meer holiday pastime! They are driven wherever the wind lifts. Mr. Lunardi, who I believe hoped to return to the Artillery-ground, was landed at Ware; and Mr. Blanchard, at Rumsey in Hampshire: of course, nothing has been effected, but to enable particular men to boast that they have been up with a balloon; and to furnish idle people with exhibitions, raree-shews, and ridiculous processions! Mr. Blanchard in his advertisement fixed an early hour for setting off; adding that he should be punctual to his time, because, after certain manœuvres, he proposed to go as far as the length of the day would allow. These manœuvres, by report, were to make a complete circuit round the metropolis; which would have distinguished him as the first governor of the machine. But when the hour came, and the balloon rose, no manœuvre whatever was performed but by the wind, which, without the least ceremony, carried off this bold rival in a direct steady course into Hampshire!
  One trial would shew as plainly as five hundred, that there is a kind of elastic air, so much specifically lighter than atmospherical air, that heavy bodies may be carried off the ground by the difference between their respective gravities; but this knowledge as yet, is absolutely barren, notwithstanding all the pompous relations we have received of aerial voyages performed abroad; and all that we have seen at home. Let us not then lavish any ore money in brewing this noxious fluid; nor wantonly injure the Public, by every now and then depriving them of a day's labour of 100,000 working people, and ruining all the cultivated grounds in the neighbourhood of the exhibition; before we have, by mature theory, endeavoured to render the discovery subservient to some useful purpose. I will only add, that your Correspondent X, p. 333, where he says, "perhaps, even in the "ordinary way of parading in the air, a parcel "of smaller balloons, connected together, "might be more safe and eligible, than one of "enormous size, upon which solely we have "to depend;" does not appear to advert to a circumstance, nevertheless sufficiently obvious, which is, that an equal quantity of inflammable air in one balloon, will perhaps raise four or ten times the weight it would if the containing materials were multiplied.
  To stimulate more able heads than mine to the task of improvement, is the object of the present letter; in hopes that, by throwing out a few cursory hints, even my mistakes may be of use, by leading to more correct principles.
  I apprehend a bird is the model we ought to aim at as nearly as possible, in  constructing the apparatus to govern a balloon. If we examine the figure of a bird in the act of flying, we shall find his wings, the sustaining power, very large in proportion to his body; If we examine a balloon, with such wings as we have hitherto seen, we shall find 
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this proportion inverted! A balloon will indeed float without wings; but this advantage is much more than merely lost, when we attempt to give an additional weight to the balloon, and direct its course by wings; owing to the vast size of the body opposed to the resistance of the air, which must be powerfully counteracted by those wings. In must also have a rudder corresponding with the tail of a bird; and whoever has noted the flight of large birds, will perhaps conceive the head and neck of a bird to be no less useful in directing its course before, than the tail behind. When art therefore is employed to imitate nature in like circumstances, no advantage whatever is to be overlooked. A loose scheme of what I mean, may greatly assist the Reader in conceiving my ideas, save a multitude of words, and facilitate his own reflections. 

[[image - crude drawing of a round balloon attached to a basket below, with a bird between attached to the balloon by wire]]

  In the above rude outline, I suppose a rudder made of silk or canvas, stretched in a light wooden frame, under the balloon, to be continued across, and projecting before, like the head and neck of a bird, balanced by a lath at the top, but sustained and made to be turned easily below. The floating balloon will, I am persuaded, conform to the central direction given to it, and the wings will then work according to the desired course. But as the tails of most birds are flat, and lie horizontally, it may deserve consideration, whether the rudder, where it expands behind, should not lie horizontally, it may deserve consideration, whether the rudder, where it expands behind, should not lie horizontally also; and whether a power or raising or depressing it vertically, would not influence the course of the balloon in rising or sinking? Or whether, as I proceed on the supposition of two navigators, one to work the wings, and another to act as steersman, this purpose may not be more readily accomplished by the gallery being lengthened like a boat? The steersman in that case, by removing himself fore or aft, might by his weight raise or depress the head of the machine, and thus dispose it to soar, move level, or incline downward. A pair of large wings framed with whalebone (which there is not room to add to the figure) should be fixed strongly in an horizontal position to the sides of the gallery, and be worked by a windlass within. When the tips of the wings are brought down by a cord, to a
[Price Threepence.]
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proper degree of depression, the cord being let slip, the wings will spring back to their horizontal extension: a mechanical head will easily apprehend my meaning, without my laboring at minute explanation. Thus, by the help of a rudder, I conceive the possibility of steering a direct course, of turning that course into another direction, or of making a circular sweep like a pigeon; and by elevating or depressing the head or front of the gallery, of soaring or tending toward the earth, without carrying a load of ballast to be parted with, or unnecessarily diminishing the more valuable contents of the balloon. If these loose thoughts should be convertible to any practical use, my purpose will be answered; for until some actual improvement is attempted, going up with balloons is meer philosophical trifling, and ought always to be met by Englishmen with the interrogation   CUI BONO?
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[[Image - line drawing: balloon in flight, attached by wires to a masked, winged harlequin holding a weighted bag in each hand. A man is "riding" him and holding a whip]]

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^[[1784. - handwritten in ink]]
For the London Chronicle.
On the Direction of AIR-BALLOONS.
IT will be allowed to be a thing impossible to direct the Balloon in the manner of a ship, by employing sails, if the following circumstances are attended to: - That a ship under sail, going upon a different direction from the wind, receives a motion which is generated between two elements; for every seaman knows, that a ship will not lye up to the wind, as it is termed, without having a proper hold of water; hence it is, that a flat-bottomed Dutch vessel must let down her lee-boards to prevent the wind driving her to leeward. Therefore, as a Balloon moves but in one element, it must be obvious that sails cannot alter its course.
  Whilst there is no wind, oars may be employed to some advantage; but as they bear no proportion to the size of the Balloon, they can have as little power over it, as a small boat dragging through the water a large ship; and as every thing respecting the two elements are analogous, it must appear a thing impossible for a Balloon to move against a current of air, going at the rate of 20 miles in the hour. Oars may, however, be employed in raising or lowering a Balloon: for, as it floats nearly upon an equilibrium, little force is required to raise or depress it. The power most effectual to steer the Balloon in any direction, would be to make use of wings; but thee, it is to be apprehended, cannot be employed upon a great scale, without using such machinery as will be bound too weighty for a balloon to take up. However, though an aerostatical machine cannot be employed as a vehicle for travelling through the air, yet it is probably it may be found useful in extending science. Great light, perhaps, may be thrown upon that sublime part of physics, the doctrine of attraction, by a strict attention at different heights in the atmosphere, to the barometer, and the oscillations of the pendulum, and the cause of the various phenomena in the upper regions, it is probable, will be explained upon more clear principles than has yet been offered.
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PLAN for directing an AIR BALLOON.
^[[Jan: 1785. -handwritten in ink]]
  In order to give a horizontal direction to an Air Balloon, it seems absolutely necessary that some force should be found, which may act on the Balloon in the same plane with the wind; and from reflecting on this necessity, the thought occurred or applying to this purpose the repulsive force of gunpowder. That it should be adequate to the desired effect, can scarcely be doubted by any body, who considers the violence with which a cannon recoils, or the rapidity with which a sky-rocket mounts in so short a time to so prodigious a height. the velocity of the rocket's flight, and the weight of the cannon, shew this force to be immense. What then should be its effect on a Balloon, which, notwithstanding all the absolute weight of its appendages, being still relatively lighter than a feather in the air, would not oppose any the least weight whatever to be overcome? It may be said, perhaps, that it would be dangerous in the application; but besides that the Balloon might be easily fortified against all risqué, it must be recollected that this force being repulsive, would be constantly and rapidly driving the Balloon from the sparks, and out of the reach of danger. In order to procure a constant succession of force, one might avail oneself of an imitation of either of the machines below-described.
  There is in the arsenal at Brussels the model (or perhaps it may be the original) of a piece of artillery, which belonged formerly to the Emperor Charles V. It consists of one solid piece, but has seven touch-holes, and as many bores, which are so contrived that you may discharge each separately, at what intervals you please, or, by applying the match at one particular touch-hole, let them off all together.
  The other piece was invented in the time of Lewis the Fourteenth, for the purpose of bombarding St. Maloes, and the model of it is now shewn at the Palais Royal at Paris. It consists of a considerable number of cannon, (as well as bombs) which diverge from a point in which all their butts meet: the match being once applied, they all go off in succession, and by means of the machinery on which they are placed, each cannon, before it is discharged, is brought into the direction of the one which preceded it.
  It is now more than a year since this thought was first conceived, and it has been communicated from time to time to a few individuals only; but as yet it has never yet been tried.
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