Mac Sweeny, 1844, Essay on Aerial Navigation
- Joseph Mac Sweeny, M.D. An Essay on Aerial Navigation, Pointing out Modes of Directing Balloons. Second edition revised. Cork: George Purcell & Co., 20, Patrick Street. 1844.
Read online at Google Books.
Mac Sweeny circles around some key themes, which include the main problems to be surmounted (essentially, propulsion and steering), some innovations which he think will work, and his optimism for the future of aeronautics, in spite of those who ridicule the field as a frivolous dead end.
Revised version of essay first published in 1824, which latter the author says he wrote "with more haste than discretion."
the Propulsion problem
Looks at the seemingly intractable problem of balloon propulsion, which contemporary sources treat as hopeless, according to Sweeny. (iv)
He mentions an idea of avoiding an engine by simply generating steam and emitting it from a pipe (i.e. a jet). However, he writes, this approach fails because of the difficulty of keeping the vessel pointed in one direction, rather than whirling around and around as it emits steam. (v) In fact:
Power of any kind is useless, if we cannot keep a balloon from spinning. It has been assumed, that a rudder will prevent spinning, an error which has deceived many. (13)
However, despite efforts at constructing a "fish shaped" aerostat, "there is the difficulty of keeping the end forward, and of preventing the machine from turning the side." (13)
Another statement on the possibility of true aerial navigation, quoted from a paper on Aerostation, read before the Cuverian Society of Cork, 2 May 1838 (p. 41):
High authorities in pronouncing air navigation hopeless cannot prevent persons from thinking differently, if impelling on correct principles be proposed. The day has passed, when high names could stop discussion. [...] It is not to be expected, that the aeronautic art will burst at once into maturity; to show that it is capable of any improvement, is a point gained. A body when moved from rest, can be more easily urged forward.
McSweeny described an idea of his, published in the Southern Reporter, 26 August 1824. Partly he intends to solve the problem of oars attached to a hanging car, which propel the car but not the whole vessel.
A platform is formed of hollow rods, on which cloth is spread, the platform is supported by balloons, there are two cars, a rod goes from one car to the other, and checks oscillation. Rods go up to the platform from the cars. The oars are attached to the platform, and are worked by cords from the car. A weight and springs brings the oar to its former position, after each pull. The chief fault of this, and of Pauly's plan was, that there was no effectual way of preventing the machine from turning the side. (14)
Two connected balloons
Letter to the Cork Chronicle, 21 September 1835:
Let us suppose two balloons to ascend at the same time, and to have their cars connected by a long light pole, this would prevent each car from revolving round its own axis, an inconvenience much felt in aerial navigation, and if a surface of silk be given off from the sides of this pole to imitate the feathers of a quill, the pole could be turned to present the silk in the vertical or horizontal position, as occasion might require.
(Two balloons could also be connected with a cord and perform some maneuvers by changing the distance between them.)
The Southern Reporter, 17 December 1836:
"It is easy to make two balloons ascend and descend alternately, without loss of gas or ballast. It may thus be effected. When two balloons are connected by a long rope, furnished at intervals with rings, an iron chain similar in thickness and shape to a round watch chain, may be used for ballast, coiled in quantities in the two cars, and may be passed through the rings of the connecting rope. But it may be asked, how is the weight of this connecting rope to be sustained? A series of very small balloons may be ranged at intervals along the rope, sufficient to float it in the air. Now the aeronauts can haul in the chain, from one car to the other. The one from which the most is taken consequently rises, and the other descends. Instead of a chain, a gum-elastic tube may be bound to the rope, and water may be pumped from one car to the other. But if the rope were very long, and if one balloon ascended high above the other, there would be danger that the water would burst the tube, therefore the chain is better in this case." (34)
Three connected balloons
Veeing is practiced with three balloons B, C, and D, connected as described under the head of Trining, but in veeing no drags are used, therefore these balloons have no drags. At first the balloons are in line, but we cause the central balloon C to descend, it being connected by a rope with B, which is to the west, and by another rope, with D which is to the east. Now, C connot descend, without causing B and D to swing towards each other, and the ropes while the balloons are swinging, describe a figure similar to the letter V; hence the name which I give this plan. Acquired velocity will cause B and D to pass each other, but by causing one to offer more resistance to the air than the other, one will move more quickly to W, than the other will to E, when our object is to move W.
Then elevate C again and repeat the process to travel west.
If C be not exactly in the centre between B and D, but has the connecting ropes so arranged, that it lies nearer to one than to the other, then when C is made to descend, B and D will not strike in passing, because one will pass under the other. (60)
Mac Sweeny explains that at various times he has advocated "balloon ways", that is, tracks between important locations for dedicated traffic routes. He goes into detail, describing advantages of using such balloon routes in thinly populated areas, like eastern Russia, and by the British empire in India and Australia. In Europe he suggests connecting balloon ways with railroads. In all cases he suggests they can be used for air mail and light cargo. (pp. 71–75)
Mac Sweeny's bibliography
His bibliography includes:
- Dr. Forster's Aerial Voyage. Phil. Mag. for 1831.
- Memoire sur la direction des aerostats par E. Gire, Paris 1843.
- too many more works to retype here, found on pp. 83–86
- includes Jeffries, 1786, Narrative of Two Aerial Voyages and Baldwin, 1786, Airopaidia; certainly a good reference for in-depth research into the early ballooning period
- Forster, 1832, Annals
- Cavallo, 1785, Aerostation
- several works by Depuis Delacourt [probably Dupuis-Delcourt]
- "Edgeworth on the resistance of the air. Phil, Trans vol 73 and on aerostation, Phil, Mag, vol 47"
- dozens of articles in Mechanics' Magazine, especially vols. 25–39
Empire of the Air
He gives the verse, attributed to young Louis XVIII, and loose English translation, which might be the source of the phrase "empire of the air", later the title of a book by Louis-Pierre Mouillard:
Les Anglais, nation trop fiere
S'arrogent l'empire de la mer,
Les Francais nation legere,
S'emperent de celui des airs.
The English haughtily demand
That seas should be at their command
The French both light and free from care,
Seize on the empire of the air.
Extracted from a paper on Aerostation, read befor ethe Cuverian Society of Cork, 7 June 1837:
An art which tends to bind nations in closer union must soon be appreciated. It had to bear the ridicule of the ignorant, and the chilling neglect of the learned. It strikes at the root of barbarism. The savage will gaze at the light sphere above him, and will acknowledge the supremacy of civilized man.
From Chapter XXXI, "On the tendency of rapid intercourse between Nations to promote Peace."
Traveling tends to enlarge the mind, to banish prejudices, and to correct overweening vanity [...]
Aerostation will aid in diffusing christianity over the earth. The Gospel will be floated over mists and clouds, and will descend on distant lands, to spread light and peace. In the Apocalypse, an angel is described flying, and having the Gospel to preach to every nation.
As aerostation tends to universal peace, philanthropists must view with interest, any attempts to improve it. The bonds of commerce bind nations together, increase facility of intercourse, and the chances of prolonged peace will increase. [...]
The code of Justinian, and the code of Napoleon, will be remembered when war victories shall be forgotten, may a code of Victoria yet bet cited.
Use of balloons
Covers various adventurous and scientific uses.
Balloons have often been proposed for exploring Africa and Australia, and a small one for bringing letters from discovery ships in polar regions. Messenger balloons for conveying letters to go far, may have ballast to slowly escape, water escaping drop by drop, or sand falling as in the hour glass.
The general use of balloons hereafter, will lead to a change in revenue laws. No laws will be able to prevent the transfer of light precious articles, from one country to another, or the circulation of intelligence. (86)
|Original title||An Essay on Aerial Navigation, Pointing out Modes of Directing Balloons|
|Simple title||Essay on Aerial Navigation|
|Authors||Joseph Mac Sweeny|
|Keywords||LTA, balloon, propulsion, navigation|
|Related to aircraft?||1|