The Evolution of the Airship
The most, powerful navy that could be built, the strongest fortifications that the wit of man could devise, or the most numerous and efficient army in the world, would all be comparatively helpless and at the mercy of the nation possessing a fleet of airships so designed as to be capable of carrying quantities of high explosives, and really under the control of those who manned them.
Is the possibility of the construction of such an aerial fleet altogether remote - or is it on the eve of realisation? The present article, bracing the story of the evolution of the airship as far as it has progressed, may be some assistance in
answering those important questions.
The possibility or otherwise of travelling through the air, has exercised the minds of men from time immemorial, and although it would be both curious and interesting a very detailed description of the earlier attempts to solve the problem would we no useful purpose, still, a short account of some of the more noteworthy will not be out of place.
In the middle ages it was a very perilous business for anyone to attempt anything, of the kind, because for anyone to attempt anything of the kind, because the dangers attending the experiments were supplemented by the additional risk of being burnt at the stake or boiled in oil for witchcraft, for in those days anyone who accomplished anything out of the common was often suspected of dealing in magic, and of being able to perform his feats of skill chiefly through the secret aid of the Evil One. Notwithstanding this drawback, a great, many individuals devoted attention to the subject, and some of them claimed to have succeeded, notably one Albertus Magnus, who flourished about the first part of the 13th
century; his plan was so simple that I cannot, do better than give it in his own words: "Take one pound of sulphur, two pounds of willow carbon, six pounds of rock salt; grind these very fine in a marble mortar; place the powder in a covering of papyrus: in order to ascend and float away, the covering should be long, graceful, and well filled with this fine powder."
Other would-be aeronauts, having observed that the dew fell from the heavens during the night, and was drawn up again in the day by the Sun, conceived the idea of collecting some dew and enclosing it in a hollow sphere, and then exposing the vessel to the rays of the sun in the expectation that it would ascend. A gentleman named Lauretus Laurus in the 15th century announced that he had experimented successfully in this manner, using the shells of hens' eggs partly filled with dew and sealed up.
One of the first vessels ever seriously designed to travel the air of which we possess any really authentic record was that projected in 1670 by Francis Lana, a Jesuit; it consisted of a wicker boat or basket, to be lifted into the air by four spherical balloons, each 25 feet in diameter, made of sheet copper 1/200 of an inch thick, each enclosing a vacuum; and to be propelled by a sail and oars. This project never came to anything, because it is obvious that even if if were possible to construct such balloons, they would collapse directly an attempt was made to exhaust the air contained in them.
This proposition, although impracticable, is remarkable as containing the principle of the balloon as we know it today, and as showing the idea prevalent at that time, that the atmosphere was of no great height, and that it covered the earth like a shallow ocean; Lana's airship was designed to float upon the surface of this imaginary sea.
There were innumerable other schemes, some ingenious, some ridiculous, but, nothing was actually accomplished until 1783, when the Brothers Montgolfler, of Annanoy in France, constructed a linen globe 105 feet in circumference, which they on June 5th of that year inflated over a fire made of small bundles of straw. The balloon, when released rose at once to a great height, and descended after 10 minutes at a distance of 1.5 miles (2,414 meters). Such was the first balloon.
Two months afterwards, a balloon made of varnished silk and filled with hydrogen gas, was constructed at Paris under the direction of Professor Charles. It ascended and remained in the air for three quarters of an hour, and descended at a distance of 15 miles. This was thus the first hydrogen balloon.
The first human being to ascend in a balloon was M. Francois Pilatre de Rozier, who on October 15, 1783 went up in a fire balloon of Montgolfler principle. This aeronaut made numerous ascents, and was finally killed in an attempt to cross the English Channel in a balloon.
The first British aeronaut was Mr. J. Tytler, who made an ascent at Edinburgh on S7 August 1784 in a fire balloon of his own construction.
From this time forward innumerable aerial voyages were made. The valve was invented by Professor Charles, who also originated the hoop and net from which the car is suspended. The guide or trail rope for preventing loss of gas and ballast was introduced by the celebrated British aeronaut Mr. Green, and a number of other improvements were effected. On January 7, 1785 M, Blanchard, accompanied by Dr. Jeffries, accomplished the unprecedented feat of crossing the English Channel from Dover to Calais in a balloon; but notwithstanding the efforts of Blanchard, Lunardi and many others who sought by means of oars and other devices to steer the aerial vessel, the balloon remained essentially what it was at the first, a thing to be blown whithersoever the wind listed, and no material advance was made in this direction until 1852, when M. Giffard constructed the first elongated or cigar-shaped balloon, equipped with a screw or fan propeller, and driven by a steam engine of special design; the rudder was a triangular sail at the rear, above the car, and under the balloon.
Giffard made his first voyage on September 25th, 1852. At the time of the ascent there was a light breeze, and the airship answered the slightest movement of the rudder; later on the wind increased considerably but even in a stiff breeze, M. Giffard, although unable to drive his aerial vessel directly against the wind, was able to 'tack" and make circular movements.
The aeronaut descended in safety, after having demonstrated in a most unmistakable manner, the possibility of controlling, to a certain extent, the direction of aerial craft.
In considering the fact that this remarkable experiment was not followed by many others, we have to remember that at that period, as at the present time, a great number of those who were interested in the subject of aerial navigation were of opinion that the solution of the problem was to be found, not in balloons of any kind, but in mechanical apparatus or flying machines heavier than the air they displace. This circumstance may account for the fact that we do not hear of another dirigible balloon until 1872, when Dupoy de Lome constructed an airship very similar to Giffard's, the chief difference being that he substituted a capstan turned by four men, for Giffard's steam engine
In 1883-84 a series of experiments were made by Gaston and Albert Tissandier with a balloon of the Giffard type, the motive power this time being electricity; the results were always distinctly encouraging; even in a strong wind lateral deviation or "tacking" was accomplished with facility, and on one occasion the airship "stemmed" a wind blowing at the rate of seven miles an hour.
That the degree of success attending these experiments did not escape the notice of the French military authorities is evident, for In 1884-85 M.H. Renard and Krebs, the officers in charge of the Government Balloon Park, at Meudon, carried out a number of trials with an airship of improved design. The balloon was 165 feet in length; the maximum diameter being 37 feet; the vessel was driven by a 9 H.P. electric motor, and two men were required to work the ship.
The first ascent was made in very calm weather, and the "La France" airship realised the most sanguine expectations, being perfectly under control, and finally returning to the starting point without accident. The second voyage was undertaken under different and unfavourable conditions; a strong wind prevailed, but in order to submit the airship to a severe test it was decided to make the ascent.
When the ship rose into the air it immediately began to drift before the breeze, but directly the power was transmitted to
the propeller - or in this case more properly, tractor - and the steersman began to manipulate the rudder, the balloon turned its head to the wind and - remained stationary. The motor was taxed to the limit of its powers, but still the airship was unable to go forward; for ten minutes the unequal struggle continued, and then the aeronauts observed with alarm that the motor was becoming overheated, and to prevent a worse calamity even than failure, the current was switched off, and the vanquished airship again drifted before the victorious wind, being eventually towed home by the soldiers of the Balloon Corps.
Some of those who had been extravagantly elated over the performance of the "La France" on the occasion of her first trial, were also excessively disappointed with the result of the second: to the aeronauts it merely proved that with the very limited driving power then at their command, it was impossible to travel directly against a strong wind; their subsequent experiments proved that if they had tried to reach their objective by means of lateral or or tacking movements they would have succeeded. Altogether the "La France" made seven voyages, and on five of those occasions succeeded in returning to the starting point.
Since that time there is no doubt that the French Government has given this important matter the attention it deserves;
what they have actually accomplished it is of course impossible to say, the secrets of the design of the latest French war balloons being jealously guarded, but it is believed that they possess steerable airships capable of travelling at from 22 to 30 miles an hour.
That Germany takes a keen interest in aerial navigation is shown by the experiments which were made in 1897 and subsequently with airships of various types. In that year Dr. Wolfert ascended in an airship of his own design; the balloon, which was cigar shaped, exploded in the air, and Dr. Wolfert and his assistant were killed.
In the same year an aluminum balloon (which was not completed until after the death of the inventor) was constructed by the German government and made its first and only voyage, for owing to the slipping of a driving belt the trial came to a sudden and almost tragic conclusion. The inexperienced aeronaut, finding himself unable to right the disordered machinery, opened the valve, the balloon descended with a rush and was damaged beyond repair, while the aeronaut narrowly escaped with his life. The balloon was only seven minutes in the air.
More successful was the monster airship constructed by Count Zeppelin, which made its trial trip in June l900. This is the largest elongated balloon ever built, being 420 ft. long and 39 ft. in diameter, containing 400,000 cubic ft. of hydrogen. There are two boats or cars suspended from the balloon, and the crew consists of five men.
On the occasion of the trial trip the airship developed a speed of eighteen miles an hour, but owing to an accident to some part of the machinery, the journey came to an abrupt end, after a run of only three and a half miles; the airship descended safely, and the results of later ascents have not been made public.
The recent experiments of Santos Dumont, Severe, Spencer, and others, are familiar to all, and need not be described here, but this article would be incomplete without some reference to the dirigible balloon which Dr. Barton is building for the British Government. This airship is similar to some of its continental predecessors to the extent that it consists of a car suspended from an elongated balloon, but there the resemblance ceases, for the oar is of an altogether different shape, and there are six propellers of original design. Dr. Barton has also added three sets of air planes, designed to prevent the loss of gas and ballast which has hitherto been such a serious obstacle to successful aerial navigation. This vessel is not yet completed, and its capabilities have yet to be tested, but it is safe to say that Dr. Barton's ship is a distinct advance on any of its predecessors known to the general public.
To conclude this necessarily brief and restricted enquiry into the present state of the art of aerial navigation it may be said that it has been demonstrated beyond question that it is possible to construct dirigible balloons which can be driven in any desired direction on calm days or on days when only moderate winds prevail; and it should be remembered that these favourable conditions exist on a very large proportion of the days of the year.
Further, even under unfavourable conditions it is possible to control an airship to the extent of considerable lateral deviation from the direction of a strong wind, and to make circular movements.
That an airship which can be controlled to this extent is undoubtedly better than an ordinary spherical balloon which cannot be controlled at all except as regards its vertical direction.
Robert Tressell (c.1902)
Reg Johnson custodian of The Robert Tressell Family Papers,
6 Arkendale, Whittington College, Felbridge, East Grinstead, West Sussex, RH19 2QU