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> fc -irt ^ 











Captain and iBtlruclar in tht Pruiiian BmUobh Carps 









/ '-yt'-'V 




The modem application of ballooning to scientific purposes has 
caused a widespread interest to be taken in the sport, and this 
has been intensified by the successes which have attended the 
efforts of Santos Dumont and the brothers L6baudy in another 
direction. The present moment, therefore, seems to be suitable 
for a survey of the development of the art, and, in making this 
attempt, the author has drawn on a large number of sources 
that have not hitherto been accessible to the general reader, and 
has also supplemented the historical outline with the result of 
many years of practical experience. The following pages contain 
a rough sketch of the past and present state of the art, and its 
applications to scientific ends, and further it is hoped that the 
looker-on may find in them something to help him towards 
understanding the various problems which are now calling for 
solution and afford such a fruitful subject for discussion in the 
daily press. Certain matters have been described in some detail, 
such, for instance, as balloon photography and the use of the 
carrier pigeon ; and this has seemed to be desirable, seeing that 
hitherto no trustworthy information on these subjects has been 

Balloon photography has been very carefully studied of late 
years. The author can lay claim to considerable experience in 
this department, and has made about eighty ascents, mainly for 
photographic purposes. He has also had the advantage of 
Professor Miethe's assistance on many of these occasions, and 
Lieutenant-Colonel Klussman, who was formerly in command of 
the Prussian Balloon Corps, has also kindly contributed much 
valuable information as to the various optical phenomena that 
arise in balloon photography. 

Herr Bernhard Floring, of Barmen, has also been good enough 
to give the author the benefit of his long experience in the matter 


of the carrier pigeon. The chapter which deals with this subject 
contains a good deal of general information, and is not merely 
confined to the use of carrier pigeons in connection with balloons. 
The author has for many years devoted himself to the breeding 
and training of these birds, and feels that the sport deserves 
every encouragement. It is hoped that something may be done 
towards increasing its usefulness, seeing that it might be of 
untold value in time of war ; but it must be admitted that up to 
the present little has been done on a systematic basis, and it is 
entirely neglected by most balloonists. 

The importance of the scientific application of ballooning 
entitles it to careful consideration, and such work is here fully 
discussed. The author had the honour of being elected a member 
of the international commission which was appointed to consider 
matters connected with the application of ballooning to scientific 
ends, and has had the pleasure of working with Professor 
Assmann and Professor Hergesell, whose work in exploring the 
upper layers of the atmosphere places them in the front rank of 

The flying machine, which includes all devices which aim at 
the imitation of the flight of birds, is on the other hand rather 
briefly discussed, inasmuch as from the practical point of view 
little of real importance has been accomplished in this depart- 
ment. But it is more than probable the future will have 
surprises in store for us, and that the hopeful views, lately 
expressed by the Academie des Sciences, will prove to be justified 
in so far as the results which may be expected from work on 
these lines is concerned. 

Generally speaking, it may be said that in the following pages 
all questions are fully discussed which lend themselves to popular 
treatment and appear to be of general interest. Many years of 
experience in connection with balloon clubs, specially those of 
Strassburg and Berlin, coupled with the outcome of lectures 
delivered in connection with the Prussian Balloon Corps, lead 
the author to think that information on many of the points which 
are here discussed will be of service to those who take interest 
in these matters. 


A certain amount of theoretical investigation was unavoidable, 
but it has been reduced to the smallest possible limits. There 
is not enough of it to frighten anybody, and it may further be 
said in self-defence, if any should be found to complain that 
there is too little of it, that the author had no intention of 
writing a technical textbook. It has been his wish that the 
reader may find amusement and instruction to be pleasantly 
combined in these pages, and may derive both pleasure and 
profit from the review of past and present. 

Bbblin, October, 1906. 










vm. „ „ „ 1898—1906 61 


X. KITES 116 

















IKDBX 868 


no. PAOE 








FOR BALL00NI8T8 '* 7 



















24. DUPUY DE Lome's balloon, 1872 51 












JlOvV ...I .■••.... t)| 

A. b 






38. rozb's double balloon 



41. CAR OP L^BAUDY's balloon 

42. l^baudy's dirigible balloon 




46. DBGBN'S flying MACHINE 







65. DITTO ........ 























77. millet's kite CARRYING OBSERVERS 




























*1C. PAOE 

78. cockino's pakachute 125 

79. frXulein kathe paulus preparing to descend in her para- 

chute 126 

80. fraulein kathe paulus with her double parachute . 126 

81. pall of a parachute 127 

82. methods of transporting a captive balloon .... 129 

83. landing of a balloon in the streets of strassburg 130 

84. belle-alliance platz, berlin, taken from a balloon . 132 

85. helping to land a balloon 133 

86. a balloon about to land .135 

87. kite-balloon at anchor 137 

88. steam winch for pulling in a captive balloon 142 

89. gun constructed by krupp for firing at balloons 145 

90. sketch illustrating the method of aiming at a balloon . 147 

91. waggon carrying gas cylinders for one division of the 

balloon corps 149 

92. old method of generating hydrogen 1.52 

93. modern gas waggon 153 

94. french method of suspending the basket for an observer. 155 

95. one of the balloons is pegged down in the open field, 

and the other is sunk in a specially prepared pit . .156 

96. front and rear waggons of a modern gas equipment for 

usb in the field 157 

97. wag€k)n carrying tools and appliances, the balloon being 

packed on the top 159 

98. balloons used for wireless telegraphy on the tempelhofer 

FELD 161 















113. NET OF A BALLOON 186 




116a. DITTO 188 













125. A BANK OF CLOUDS 201 



128. HELIGOLAND 205 



































no. PAGE 



159. DR. HEROESBLL 256 




. 261 

. 262 

. 261 

. 265 

. 266 

. 267 

. 269 

. 270 







































196. FILM HOLDER 312 



»'I0 PAGE 




198. MONT BLANC, AS SEEN FROM GENEVA . itee facing jtoge 317 

199. DITTO see facing page 317 





^\'-T . .............. 32o 

20(i. RUDERSDORF 327 



210 DITTO 331 





216. BATUT'S kite for PHOTOGRAPHIC APPARATUS .... 388 













The folklore of almost every race contaiaa some myth, 
embodying the aspiration of man to add the conquest of the 
air to that of the sea. Fhrixos and Helle flew over the sea, 
mounted on the ram with the golden fleece. Dasdalus and 
Icarus attempted flight, but Icarus ventured so near the sun 
that the wax which fastened the wings to his body was melted, 
and he fell headlong into the sea. 

Passing from myth to semi-legendary history, we are told that 
Xerxes received, as a gift from his courtiers, a winged throne, to 
which were harnessed four tame eagles. Food was held before 
the hungry birds, and their struggles had the effect of raising 
the throne from the ground. Somehow or another, Xerxes seems 
to have survived the start, and our picture shows him sailing 
quite pleasantly through the air. The philosopher Archytas of 
Tarentum devised a pigeon, which could raise itself if air were 
pumped into it, but it soon fell to the ground ; and here we may 
have an early attempt to construct a " Montgolfiere." The 
Chinese, to whom the invention of gunpowder has always been 
credited, possibly made still earlier efforts to imitate flight, but of 
these little is known, though a French missionary in 1694 states 
that a balloon was sent up on the day of the coronation of the 
Emperor Fo-Kien at Pekin in the year 1306. 

Mention ought also to be made of the celebrated name of 
Leonardo da Vinci, who devoted much attention to the study of 
the problem. Sketches made by him are still in existence, and 

A. B 



from these it appears that he proposed to mount the rider on a 
kind of framework, to which devices of the nature of wings were 
to he attached. The technical details hear witness to the extra- 
ordinary aptitude which the artist possessed for dealing with 
mechanical problems. The arrangement of the bat-like wings 
is particularly interesting. On their downward movement they 
were to strike the air over the whole of their surface, bat they 
were so arranged as to 
oppose very slight resist- 
ance to upward motion, in 
consequence of the folding 
together of the various 
sections. Fiiuste Verauzio 
was the first human being 
who is ever known to have 
risked his life over the 
work. In 1617 he let him- 
self down from a tower in 
Venice by means of a very 
primitive parachute,which 
consisted of a square frame- 
work covered with canvas. 
But for many years there 
were no further imitators 
of his methods. Proposals 
of more or less historical 
interest were, however, 
made about that time. John Wilkins, Bishop of Cheater, con- 
structed a flj-ing machine in 1648, and first drew attention to 
the enormous force which could be developed by the application 
of steam. Cyrano de Bergerac developed the origuial idea of 
fastening air-bags to bis body, and then allowing them to heat 
in the sun. He aup]>osed that the heated air would have the 
eflfect of making him fly, and his muddle-headed notions are 
very similar lo those which bore fruit in the pnictical hands of 

Francisco de Lana sliowed great ingenuity in his contrivance 

I'iG. 1. — The throDe of Xerxes drawn 
through Ibe air b; four tame eaglea. 


of ihe flying ship, and in spite of his mistakes it is impossible 
not to admire the acuteness of his reasoning. He clearly under- 
stood that the air has a definite weight, just like any solid or 
liquid body, and supposed that at a great height the density of 
the atmosphere would be less, owing to decrease of barometric 
pressure. He also clearly understood that all bodies which are 
lighter than air would rise in the same way that a piece of wood 
rises from the bottom of a basin of water. Consequently he 
proposed to make four great 
metal spheres, which were to 
be connected together by 
pieces of wood, and attached 
by ropes to a boat, fitted with 
oars and sails in the usual 
way. He pro|>osed to exhaust 
the air from the metal spheres 
by filling them with water 
through an opening at the top, 
and then allowing the water 
to flow away through a tap at 
the bottom. He assumed that 
a vacuum would be created it 
the tap at the bottom were 
closed at the right moment. 
In order to prevent the boat 
from starting with a sudden 
jerk it was to be suitably 
loaded with weights ; the height to which it would rise would 
then be conveniently regulated either by the admission of air to 
the spheres, or by throwing overboard some portion of the ballast. 
His ideas on the theory of the problem were undoubtedly correct, 
and he carried on a vigorous controversy with those who advanced 
objections to his proposals. But he came finally to the pious 
conclusion that he could scarcely hope for the accomplishment 
of his scheme, seeing that God would prevent such a revolution 
in human affairs. In thej^ear lUSO Borelti makes some interesting 
observations with regard to the construction of an artificial 

B 2 

VeraDzio In bis parachate. 


bird in his book " De Motn Anitnallum," aod tried to show that 
it was impossible for a man to fly by his own unaided efforts. 
A man was, indeed, much too heavy, at any rate in comparison 
with birds, neither bad be sufficient muscular energy in the parts 
about the chest ; and further, the weight of any appurtenances 
to take the place of wings would place bim at a still more 
serioas disadvantage- This reminds us of the results published 
by Helmholtz in 1872, when he was a member of the committee 
appointed to examine into 
aeronautical problems. He 
there states in the most definite 
manner that it is extremely 
improbable that, with the aid 
of the most perfect mechanism, 
a man will be able by bis own 
muscular exertion to raise his 
body into the air and to main- 
tain it in that position. 

But Borelli gave a very clei\r 
exposition of the law of Archi- 
medes, and considered in conse- 
quence that an imitation of the 
flight of birds was impracticable. 
On the other hand he thought 
that the bladder of a. fish was a 
more hopeful suggestion, but 
be strongly opposed all schemes 
which necessitated the creation of a vacuum. In view of the 
external pressure of the atmosphere, any vacuum apparatus 
would have to be constructed of metal and must be of great 
size. Its consequent weight made the whole thing impossible, 
and arguments of this nature might well be considered by some 
of the inventors who are still at work on the problem. His 
conclusions, which were at once thoughtful and clearly expressed, 
came into the hands of many scientific men and interested them 
in the possibility of a solution. 

The science of aeronautics may be divided into two parts, of 


which the one may be called aerostatics, and the other 
aerodynamics. Aerostatical devices include those in which the 
load is lifted by filling certain spaces with a gas which is lighter 
than air, whereas in aerodynamical machines the effect is pro- 
duced by means of propellers or other arrangements of a similar 
kind, tending to cause motion throagh the air. Bartholomaos 

Fio. 4.— Photograph of Ani^burg, ebowiag the cathedral. Taken from a 
balloon b; A. Kiedinger. 

Laurenzo de Gusmann constructed an airship in Lisbon in the 
year 1685 out of a wooden basket covered with paper, and if the 
facts were true, he would seem to have been tlie first to work on 
aerostatical principles. His basket is f aid to have been filled with 
hot air, and the apparatus rose from the ground in the presence 
of the royal Court at Lisbon. Bat the investigations of Lecoma 
clearly show that two totally separate experiments have been put 
together and ascribed to one man. It seems to be a fact that the 
monk Bartholomaus Laurenzo invented a machine and carried out 


certain experiments with it, about which nothing is known ; and 
twenty-five years later, a scientific man, named de Gusmann, 
announced the construction of a flying machine, with which he 
proposed to descend from a certain tower in Lisbon. His scheme 
merely called on his head the derision of the mob, and the French 
are justified in refusing to allow any special merit to his experi- 
ments, and in claiming for Montgolfier the invention of the 
aerostatic airship. 

The monk Galien ought also to be noticed, inasmuch as he 
may be regarded as the forerunner of the brothers Montgolfier. 
His book, entitled "L*art de naviguer dans Fair,'* was published 
in 1757. He points out that careful investigation should be made 
into the constitution and properties of the atmosphere, and by 
experiment it might be found whether the principle of Archimedes 
was likely to be able to be usefully applied towards the solution 
of the problem. He concludes that in order to rise from the 
ground, a ship might be filled with the air found at a considerable 
height, which would be a thousand times lighter than water, and 
if one went still higher, would be two thousand times as light^ 
If the force tending to raise the ship were greater than that 
tending to sink it, it would be possible to lift a weight corre- 
sponding to the difference of these forces. Galien made the most 
careful calculations, according to which his airship was to be as 
large as the town of Avignon, and to be able to carry 4,000,000 
persons and several million packages. It seems marvellous to 
think that a fantastic scheme of this kind should commend itself 
to a mind that was fully capable of dealing with theoretical 

In the meantime, the rival school of thought, which believed 
in the construction of an airship that should be heavier than the 
air, had not been without their successes. In 1742 the Marquis 
de Bacqueville built a flying machine, with which he descended 
from the window of his mansion, succeeded in crossing the gardens 
of the Tuileries, and finally landed on the top of a washerwoman's 
bench in the middle of the Seine. The apparatus acting as a 
parachute, the descent was very gradual and without accident. 
However, the axioms laid down by Borelli and Helmholtz still 


hold trae, and progresa in the matter of a mere flying machine 
seema very unlikely. New typet) of a more promieing kind were 
however invented. The mathematiciao Pauctou suggested the 
principle of the propeller, which he called a " Pterophore." One 
propeller was to be on a vertical axis for raising the dead weight, 
and another on a horizontal axis for any forward or backward 
movement, a parachute being provided for the descent. The 
propellers were to be driven by hand, and though nothing came 
of these proposals, it must be allowed that a definite step bad 
been made on the path, which was to lead to future success on 
these lines. The Abbe I>esforges invented s flying machine, 
called the " Orthoptttre," which was in no way remarkable. On 
the other hand, men- 
tion should be made 
of the flying car of the 
aeronaut Blanchard, 
which in some respects 
seems to have been on 
the lines of the modern 
motor car. As a matter 
of fact, it was fitted 
with sails and wings, 
and moved at a great 

rate on the Place Louis XV. and the Champs Elys^es. Still 
Blanchard never succeeded in raising himself from the ground 
with his marvellous mechanism, and so fell a ready victim to the 
wits of the day. 

Karl Friedrich Meerwein was architect to the Grand Duke of 
Baden, and managed to construct a flying machine, which gave 
proof of a very accurate knowledge of the laws of air-resistance. 
In order to sustain the weight of a man, he calculated that an 
exposed surface of 130 square feet would be sufficient, and this 
is indeed a wonderfully good approsimation to the truth. He 
suggested that serious accidents would probably be avoided if 
experiments were made at sea and uot on land, and if this idea 
had been adopted by Lilienthal, Pilcher and others, they would 
doubtless have escaped their untimely ends. But of late yeara 


something has been done in this way. Zeppelin on the Bodensee 
and Langley on the Potomac have helped to lessen the danger 
attaching to experimental work of this kind. 

It may be of interest to examine the construction of a flying 
machine, worked by a propeller, which was shown by the French- 
men Launoy and Bienvenu to a committee of the Academie des 
Sciences in 1784. A wooden bow was pierced at its centre, and 
through the hole thus made there was passed a spindle which 
carried at either end some birds' feathers, so arranged as to serve 
the purpose of a propeller. The string of the bow was wound 
several times round the spindle, and the apparatus was intended 
to start in a vertical position. The pull of the bow on the 
cord tended to rotate the spindle and put the two propellers 
in motion. The feathers, which were arranged at an angle, drove 
the air downwards, and the little model, weighing about 8 oz., 
flew up to the ceiling. This ingenious device had many imitators, 
but no great success was achieved owing to lack of suitable 
motive power. In 1870 Penaud replaced the bow by strong 
rubber bands, but without effecting any marked improvement. 
None the less, these things deserve mention, and smoothed the 
way for Santos Dumont. 



We now^reach the history of a second attempt which has been 
made to deprive the French of the laurels attaching to the inven- 
tion of the air balloon. In 1776 Cavendish discovered hydrogen, 
and showed that it was much lighter than air. Dr. Black later 
asserted that in 1777 or 1778 he discussed with his friends the 
possibility of filling certain spaces with hydrogen, and, by a proper 
design of the dimensions, he hoped to raise a body in the air. 
He consequently considered himself to be the inventor of the 
air balloon. But it is only &ir to point out that he made no 
attempt of any sort on a practical scale. Leo Cavallo did indeed 
blow soap bubbles filled with hydrogen, and also experimented 
with rubber solution, varnishes and oils ; he noticed that such 
soap bubbles moved much faster than usual. He then tried to 
fill bladders and small bags made of special paper with the gas ; 
but it immediately escaped through the pores. He was on the 
point of trying goldbeaters' skin, when he was anticipated by the 
brothers Montgolfier. 

Stephen and Joseph Montgolfier were sons of a rich paper- 
maker in Annonay, and are undoubtedly the inventors of the 
aerostatic airship. Naturally enough, tradition reports that the 
whole thing was due to an accident. One of the brothers is said 
to have dried his silk coat over the oven and to have noticed that 
the heated air tended to lift it. But such tales lose much of 
their force when it is stated that both brothers had long and care- 
fully studied both mathematics and physics, and that numerous 
improvements introduced by them into the working of the paper 
factory were ample evidence of practical capacity. Joseph Mont- 
golfier was the first to interest himself in aeronautics, and he is 
stated to have descended from the roof of his house by means of 
a parachute in 1771. He occupied his mind with the possibility 



of mechanical devices as applied to flying machines, and discDssed 
frequently with hia brother the various treatises which existed 
on the subject, and the feasibility of suggestions which had 
been made. Galien's idea of filling receivers with air drawn 
from higher levels specially interested them, and the movement 
oE the clouds seemed to justify hopes. Accordingly they passed 
steam into a receiver, and noticed that the vessel had a tendency 
to rise in the air. However, the steam soon condensed ; they 

1. 6, — Clouds pbob^aphed fn 

therefore rei)eated tlieir experiment witli smoke, which produced 
the same effect. The smoke escaped through the pores of the 
paper bag which acted as receiver ; the results were therefore no 
better than before, and the experiments were temporarily sus- 
pended. Priestley's work on the different kinds of "air" was 
translated into French in 1770, and suggested to them the use 
of hydrogen. They filled paper bags with hydrogen, which 
escaped at once through the pores. Their next idea was that 
the clouds were supported by electrical means. They lighted a 
fire below their balloon and fed it with wet straw and wool. 
The first balloon was soon burnt ; but they constructed another 



which held 700 cubic feet and rose to a height of l.OOO^ft, 
Gradaally they carried out their experiments on a larger scale, 
and the first public exhibition was made on June 5th, 1783. 
They constructed a paper balloon, 112 ft. in circumference, and 
filled it with hot air by means of a fire placed below it. The 

, — Ascent of a " Montgolfibre." 
balloon rose in the presence of the astonished spectators to a 
height of 1,000 ft., but fell to the ground in ten minutes owing to 
the gradual escape of the hot air. 

The Academie des Sciences, which has always turned its 
searching glance on any mechanical improvement, forthwith 
iuvited the brothers Montgolfior to repeat their experiment in 
Paris. But before they were able to undertake the journey 


Paris had become familiar with the sight of a balloon in mid-air. 
Professor Faujas de Saint-Fond started a subscription list for 
the purpose of raising funds, and the physicist Charles was 
entrusted with the practical work. Charles was familiar with 
the properties of hydrogen from his laboratory work, and saw at 
once that the lightness of the healed air had caused Montgolfier's 
balloon to rise. He therefore concluded that the use of hydrogen 
would constitute a still further improvement, and would have the 
obvious advantage of decreasing the size of the receiver owing to 
its greater buoyancy. He also knew that hydrogen escaped much 
more easily than air through the pores of the envelope, and con- 
sequently well understood the necessity of making the silk 
covering thoroughly airtight. The brothers Robert, who had 
succeeded in dissolving rubber, were able to provide him with an 
excellent medium for coating his balloon, and it is interesting to 
note that even at the present day no better covering is known 
for the purpose. Hydrogen was prepared from sulphuric acid 
and iron turnings. But notwithstanding the apparent simplicity 
of the arrangements, it took four days to fill a balloon, 13 ft. in 
diameter, and required half a ton of iron and a quarter of a ton 
of sulphuric acid. The booming of cannon on August 29th, 1783, 
announced to the Parisians the impending flight of the balloon. 
In spite of heavy rain, 300,000 spectators collected in the Champs 
de Mars, and so great was the enthusiasm that silks and satins were 
completely forgotten till the balloon had made a start. It 
weighed rather less than 20 lbs., and speedily rose in the air, 
disappearing in the clouds. After a short time it was seen again at 
a great heigh t, bat appeared to be ruptured, presumably owing to 
its having been too strongly inflated. The treatment it received 
on reaching the ground in the neighbourhood of Paris was amus- 
ing. The peasants saw it falling from the clouds, and ascribed 
its presence to the agency of the devil. They therefore attacked 
it with rakes and hoes and anything else that was handy. It was 
finally fastened to the tail of a horse, and dragged about, trailing 
on the ground, till nothing was left. The Government therefore 
thought it necessary to acquaint the rustic mind with the nature of 
the new invention, and to request better treatment for it in future. 


In the meantime, Montgolfier had reached Paris, and under 
the auspices of the Academie des Sciences, constructed a linen 
balloon of curious shape. The middle portion was cylindrical, 
being 42 ft. in diameter, and 26 ft. in height ; above this there 
was a conical portion, 80 ft. high, and at the bottom the cylinder 
was closed by a similar conical piece, 20 ft. in length. The 
framework was covered with paper, both on the inside and 
outside. The balloon presented a magnificent appearance, and 
was decorated with gold on a background of blue. But the Fates 
were against the inventor. A heavy rainstorm loosened the 
paper from the linen; the linen in its turn was torn at the 
seams ; and finally, a strong wind completed in twenty-four hours 
the entire destruction of the work of many months. Montgolfier 
at once constructed a new spherical balloon, having a capacity of 
52,000 cubic feet, out of waterproof linen, and made an ascent in 
the courtyard of the palace at Versailles on September 19th. 
The car attached to the balloon took up three passengers in the 
form of a sheep, a cock, and a duck. The apparatus came to 
earth eight minutes after the start, the descent being caused by 
a rent at the top, which was probably made during inflation. 
The duck and sheep were just as lively as they were before the 
start; but the cock appeared to have suffered some injury, 
which was ascribed by the learned to the effects of the rarefied 
atmosphere, whereas it was later clearly shown to have been due 
to the fact that it had been trodden on by the sheep. 

The brothers Montgolfier were everywhere received with the 
greatest enthusiasm. The King conferred the Order of St. 
Michael on Stephen, and a pension of £iO on Joseph, while 
their father received a patent of nobility with the motto, " Sic 
itur ad astro.'* The Academie des Sciences also conferred 
honours on them, in addition to a prize of money, which had 
been set apart for distinction in the arts and sciences. Both 
were made members of the Legion of Honour, and a deputation 
of scientific men, headed by Faujas de Saint-Fond, presented 
Stephen with a gold medal, which had been struck in honour of 
his achievements. 



The enthusiasm in Paris was great, and people amused them- 
selves with the manufacture of small balloons on the Montgolfier 
pattern. Baron de Beaumanoir was the first to construct them 
of goldbeater's skin, a method which has since found favour in 
the English army. The diameter of his balloon was 18 in., and 
it was filled with hydrogen. The small skins, which measure 
about 30 in. by 10 in., are very suitable for the purpose, being light 
and airtight. Still, it must be admitted that it is a costly form 
of construction. Naturally enough many doubted wliether any- 
thing likely to be really profitable to humanity would result. 
Benjamin Franklin, who was present at one of these ascents, 
was asked by a man what was the use of it all, and replied by 
asking " What's the use of a baby ? " Similar questions are 
often asked about dirigible balloons, but the enthusiasm of the 
inventor is not easily damped. 

Stephen Montgolfier proceeded to build a new balloon, 
intended to carry passengers. It was therefore much bigger 
than its predecessor ; its height was 85 ft., and its diameter 
50 ft., the capacity being 100,000 cubic feet. The exterior was 
highly decorated, and the car, intended to hold the passengers, 
was suspended below. The balloon was filled through a short 
cylindrical opening, constructed of linen ; beneath this a pan was 
suspended on which the fire was lighted. Pilatre de Rozier was 
the first to ascend in a captive balloon ; this he accomplished on 
October 15th, 1783, when he rose to a height of 80 ft. His 
presence of mind was shown on an occasion when the balloon 
was blown against a tree at a considerable height ; by diligent 
stoking of the fire he caused it to rise above the tree and so free 
itself from the entanglement. In the same year Rozier under- 
took the first expedition in a free balloon with the Marquis 


d'Arlandee as a companion. It was only with great diffietilty 
tbBt the King waa persuaded to give his permission, as it had 
been intended to experiment on two criminals who were con- 
demned to death, and their lives were to have been spareJ if 
the; succeeded in reaching the ground in safety. Tiie King, 
however, finally gave bis consent, and on November 21st, 1783, 
Filatre de Bozier and the Marquis d'Arlandes made a journey 
lasting twenty-five minutes. Tbey came safely to the ground, 
but the balloon immediately collapsed, and Rozier was almost 

S. — PortjeDgrat, an Alp[ne pefik. Photograph bj S[>elt«rii 

buried beneath the ruins. He was, however, rescued by ]hiB 
companion, and able to crawl out into the open. Similar 
accidents happen nowadays in calm weather if the landing causes 
any rupture in the body of the balloon. The gas then escapes 
very suddenly, and the balloon collapses without any warning. 
Some years ago, an Austrian officer would have been suffocated 
in this way if he bad not received timely help from liia 

Increased interest continued to be taken in the sport, and 
venturesome ladies occasionally mounted the car. On June -Itb, 
1784, at Lyons, Madame Thible ascended in a free balloon in the 
presence of King Gustavus III. of Sweden. The journey lasted 


three-quarters of an hour, and a height of 9,000 ft. was reached. 
Still it soon became apparent that great disadvantages attached 
to balloons of the hot-air type, and the danger of fire was great, 
both before and after the start. Fire-extinguishing contrivances 
were always at hand during the filling operations, and notwith- 
standing this, more than one balloon was completely destroyed 
by the flames. On landing there was always trouble owing to 
the fact that the body of the balloon fell on the pan, which was 
often still glowing hot. The danger both to person and property 
which arose from the use of hot air made any extended use of 

Lcccssful landing. 

this type of balloon out of the question. It was further impos- 
sible to carry any large amount ot combustible on the journey, 
and tliis limited the distance that could be travelled. The 
method originally used by Montgolfier of burning a mixture of 
straw and wool was found to be the beat, as it produced a bright 
and lively flame without much smoke. Saussure, the well-known 
physicist, had proposed to use alder wood in place of straw. In 
order to study the question carefully and to note the necessary 
conditions he bad remained on the car of one of Montgolfier's 
balloons for eighteen minutes during the preliminary inflation, 
in spite of the great heat. He proved thereby that the hottest 
air at the top is tree from oxygen, but contains great quantities 
of the gases ot combustion and water vnpour. He also showed 


by means of laboratory experiments tbat the ascent of the 
balloon is caused not by the heat directly, bat by the rarefaction 
of the air thereby produced. The weights and lifting powers of 
the air at different temperatures are somewhat as follows, 
assuming a barometric pressure of 30 in. of mercurj : — 

Temperature in 

Weight per cubic foot of 

Lifting power per cubic foot 

degrees Fahrenheit. 

air in lbs. 

in lbs., compared with iVP F. 


















At a height of 8,830 ft., a cubic foot of air at a temperature of 
32° Fahr. weighs only 0*059 lb., and therefore a " Montgolfiere '* 
cannot reach a greater height than this, seeing that the '* lift " 
then disappears, unless the temperatures, given in the above 
table, can be exceeded. 

All these considerations tended to show that the type associated 
with the name of Professor Charles was better. He had indeed 
specially built a new balloon 30 ft. in diameter, for the purpose 
of atmospheric observations. The construction of Charles' 
balloon was very similar to that in use at present, and it may 
therefore be of interest to describe it more minutely. The silk 
covering was coated with rubber solution, as has been already 
stated. An outer net was also employed, which was intendea 
partly to support the silk covering, and partly to distribute the 
pressure more uniformly over the whole surface. The net, as 
used by Charles, covered only the upper half of his balloon, and 
ended in a wooden ring, which was connected to the car^by 
ropes. The length of these ropes is a matter of importance. 
From the point of view of diminishing the load, it is well [to 
keep them as short as possible; but on the other hand, the 
danger which may attend the escape of gases from the balloon 
makes it impossible to place the car too close to the body. In 




Germany it is usually suspended about 8 ft. below the body ; in 
France the two are placed much nearer to one another. Many 
accidents have taken place in France with balloons filled with 
hydrogen prepared from sulphuric acid and iron. Sulphuric 
acid is very liable to contain arsenic, which easily passes with 
the hydrogen into the balloon, and is fatal in very small doses, 
several aeronauts having met their deaths in France owing to 
this cause. The method which Charles used for the construction 
of his net is still in vogue, but it is now so arranged as to cover 
the entire balloon. He made a marked improvement by placing 
a valve at the top, and by this means he was able to allow the 
gas to escape at will. The most ordinary kind of valve is some 
form of the plate or butterfly type. The original construction 
consisted of a wooden ring with a transverse strip, to which two 
flap valves were fastened by means of hinges. These valves 
were operated from the car by means of ropes, and were normally 
kept closed by springs, which pressed them against their seatings. 
In another form of valve a flat plate is pulled away from its 
wooden seating, allowing the gas to pass out sideways. In order 
to ensure the tightness of the valve, the plates or flaps have 
sharp edges, which are pressed against a rubber packing. It was 
formerly the practice to use a special kind of luting to ensure a 
good fit, but after the valve has been opened and shut a few 
times, such a joint becomes almost useless. Generally speaking, 
the valve is only used for the purpose of effecting a descent ; any 
other use only results in loss of buoyancy with a consequent 
shortening of the time during which the journey can be continued. 
It is of course also used in order to fall to a lower level, in the 
hope of finding more favourable breezes. 

At the bottom of Charles's balloon he had a tube about 7 in. 
in diameter, through which the gases were passed into the body 
of the balloon, and through which they could also escape in case 
of any rise of internal pressure. This neck is nowadays generally 
left open. The diminished pressure on rising causes the gases 
to expand, a result which may also be caused by an increase of 
temperature. If, therefore, this openuig were closed, and the 
pases were unable to escape, the whole balloon might be shattered. 


The length and diameter of the opening must be somewhat in 
proportion to the contents of the balloon, and suitable sizes can 
be calculated by anyone with sufficient general experience. 

The gas was prepared by Charles by the reaction of sulphuric 
acid on iron turnings, which were therefore mixed with water in 
barrels, and on the addition of sulphuric acid the reaction imme- 
diately took place. The gas must be washed by passing through 
water, and is then cooled and dried. The various processes are 
not, however, quite so simple as would appear at first sight. 
Sulphuric acid is a corrosive fluid, and lead is one of the few 
substances which it does not attack ; consequently it is extremely 
difficult to get the gas in a state of purity. As a matter of 
historical interest, it may be pointed out that the first gas 
explosion took place over the filling of one of these balloons, 
and was caused by a lamp which was brought near a leaky 
barrel. This is caused by a mixture of two volumes of hydrogen 
with five of air; the heat of combination expands the water 
vapour, which is formed by the reaction, to such an extent as to 
cause a very violent explosion. It took three days and three 
nights, with the aid of twenty barrels, to generate 14,000 cubic 
feet of hydrogen, but at last, on December 1st, Charles had 
completed all his arrangements for the ascent. 

The fittinp;s carried on the car of the balloon included many 
novelties. For the purpose of facilitating the descent during a 
heavy wind, he carried a kind of anchor, which was fastened at 
the end of a long rope. His idea was that the grapnel would 
hold the balloon at a safe distance from the ground until it was 
possible to allow a sufficient amount of gas to escape through 
the open valve and so complete the descent. He also carried a 
barometer, which he had himself constructed for the purpose of 
determining the height to which the balloon had risen, and 
herein may be seen the result of the ideas which originated with 
Lana and Galien. In order to determine the direction of the 
wind before starting, Charles had provided a small pilot balloon, 
6 ft. in diameter, which he handed to Montgolfier with the 
words, " C'est a vous qu'il appartient de nous ouvrir la route des 
cieux." The good feeling thus shown to Montgolfier showed that 

c 2 


no bitterness existed between the two inventors, although it is 
undoubtedly true that there was a very lively controversy as to 

FiQ. II.— I'aris, shoviiug the Eiffel Tower. Pbutogtapb by C 

the merits of the rival Bchemes. It is impossible to deny that 
Charles showed great originality in all his work. The shape of 
his balloon was indeed the tame as that ot his rival's design, 
but it is obvious that no other shape was reasonably possible. 


seeing that he must have well known that a sphere combmes 
the greatest volume with the smallest surface. In the pilot 
balloon he invented an auxiliary which^is of great use in meteoro- 
logy as well as in aeronautics, and it is obviously of importance 
to know beforehand the direction of the overhead breezes. The 
Abbes Miollan and Janinet had a special method for using them 
during a voyage. They proposed to keep one small balloon, 
filled with hydrogen, at a height of 160 ft. above the main track, 
and a second, filled with air, at the same distance below. In this 
way they would be able to determine the direction of the breezes 
over a vertical space of 300 ft. Suggestions of this kind are, 
however, of no great value. The direction of the wind at a level 
below that of the car can easily be found by throwing out small 
pieces of paper; and an overhead pilot would be completely 
hidden by the body of the main balloon, unless the rope by 
which it was attached was inordinately long. Moreover, there 
are other and obvious difficulties attaching to their use. 

These pilot balloons have played a great part at popular 
festivities, on which occasions their weird shapes and many 
colours have added to the gaiety of the scene. From the 
professional point of view, displays of this kind are of no im- 
portance, but one occasion may be noticed on account of its 
historical interest. A raan named Garnerin was well known on 
account of his many descents by means of a parachute. He 
was therefore commissioned to send up a pilot balloon on the 
occasion of Napoleon's coronation in 1806. This was done, and 
the balloon found its way to Rome, where it descended on the 
tomb of Nero. Napoleon regarded this as an evil omen, and 
is supposed to have conceived a violent antipathy to ballooning 
in any form, even in its application to military purposes. 

Charles made his ascent with one of the brothers Robert 
oil December 1st, 1788, in fine weather before a large con- 
course of people. He afterwards wrote in glowing terms of the 
delight which he experienced on journeys of this kind. On this 
particular occasion they covered about 40 miles in 3f hours and 
arrived at Nesles, where Robert landed, while Charles continued 
his journey alone. He then rose to a great height, and was 


exposed to the utipleasaut eSects of the rare&ed atmosphere. 
In coDeequence of the very rapid ascent he experienced great 
pain in the ears, besides suffering acutely from the cold ; be 
therefore opened the valve, and came to earth in 35 miQutes from 
the start, at a distance of a few miles from tlie spot where he 
had left his friend. The balloon had been satisfactorily tested 
in every way. In particular, the benefit of the open tube at the 


Fig. 12.— a balloon in the act of laiiiling. To the right of the basket is seen 
the ballast-sand, which has just been thrown out. 

bottom was very evident on the occasion of the second journey, 
when tlie gas streamed out in great volumes under the diminished 
pressure. After Robeit had landed, he had forgotten to take on 
board a corresponding quantity of ballast. At starting he had 
filled the car with as many sacksof sand as he could carry, but he 
forgot to give tlie matter further attention. It is impossible so to 
construct a balloon that the gas shall not be able to escape through 
the substance composing the walls. This is due to a property of 
gases called diffusion, of which mention will be made hereafter. 



Charlee' balloons, which were called the "Charliere," the 
" Charlotte," and the " Robertine," had been completely succesB- 
ful, and had altogether eclipsed the efforts of Montgolfier. The 
King of France ordered a medal to be struck on which Charles' 
head should iigure beside those of the brothers Montgolfier, and 

," conslruoteii by I'ilAti' 

in this way he proposed to do honour to all the inventors 

Tlie balloons, called " Rozieres," which were made by Pildtre de 
Eozier, were even lesa successful than those of the hot air type. 
Kozier was, anxious to have the distinction of being the first to 
cross the English Cliannel. But he was anticipated by Blanchard, 
whose rivin}; car has Iteen already mentioned, and wlio had since 
those days Iweome a professional balloonist, .\ number of 
ascents hud been made in different places on the Continent, and 


he now proposed to make the journey from Dover to Calais. A 
start was made at Dover on January 7th, 1785, in company with 
an American doctor named Jeffries. He took with him a variety 
of useless things in the shape of oars, provisions, and much else. 
The w^hole thing would have sunk in the water at the moment of 
starting if all the ballast had not been thrown overboard. With 
great diflSculty they succeeded in covering half the distance, 
though they were obliged to throw away everything on which 
they could lay their hands, including a mass of correspondence 
and books, together with most of their provisions. They then 
sighted the French coast on the horizon, but the imminent 
collapse of their balloon made the outlook anything but hopeful. 
Blanchard now threw overboard the wings, which he had stated 
were necessary for the support of the contrivance and for guiding 
it in any given direction through the air. This did not produce 
the desired result, and they began to strip themselves of their 
clothing ; but it only sank further and further, till Dr. Jeffries 
proposed to lighten the load by jumping into the water. How- 
ever, this plan proved unnecessary, as also was another scheme 
for cutting the car away from the balloon. Suddenly they rose 
in the air, and with great difficulty they effected a landing on the 
coast near Calais, where they were received with many rejoicings. 
A marble column with suitable inscription was erected on the 
spot, to convey to future ages the facts relating to the first 
crossing of the Channel by balloon. 

Pilatre de Bozier thought much over this adventure, and 
determined to repeat it at all hazards. The difficulties into 
which Blanchard and Jeffries had fallen were to be avoided by 
constructing a special form of balloon. He proposed to combine 
the ideas of Charles with those of Montgolfier, hoping to be able 
to balance the losses, due to the escape of hydrogen, against the 
lifting power, which he could generate, as required, by means of 
hot air. He therefore made a spherical balloon after the 
methods of Charles, and placed below it a cylindrical receiver, 
which could be filled with hot air. The rope for controlling the 
valve was brought down on the outside. He thought, by suitably 
regulating the heat of the fire, to be able to rise or fall, and the 


careful study which he had given to this aspect of the problem 
led him to think that this would constitute a very desirable 
feature in the combination. He determined to start from the 
French coast, but was obliged to wait a long time till there was 
a favourable easterly breeze. At last, on June 16th, 1785, he 
started with a friend in the '' Aero-Montgoltiere," as it was 
called. The balloon rose rather rapidly, and remained stationary 
for a short time in the air. It then fell suddenly on the cliflf, 
and both passengers lost their lives. According to the testimony 
of those who witnessed the accident, a cloud was seen round the 
balloon just at the moment when it fell. An explosion was 
therefore the probable cause of the accident, and this seems very 
possible, seeing that it is alleged there were slight leakages of 
hydrogen, which were noticed before the start. 

This accident had the effect of cooling the ardour of enthusi- 
asts, and the number of journeys that were made decreased very 
rapidly. Count Zambeccari, an Italian, had little better luck 
than Rozier. He heated the hot-air balloon with a large spirit 
lamp. At his first attempt he had the misfortune to fall into 
the Adriatic, but was rescued by some sailors with the loss of his 
balloon. At his second attempt, the heating arrangements worked 
admirably, but as he was descending the lamp was upset, and the 
car was set on fire. His companion displayed great agility and 
reached the ground with the help of the anchor rope. But the con- 
sequence of this, and of the great heat, was that ihe car suddenly 
rose to a great height, where Zambeccari succeeded in extinguish- 
ing the flames. But this was no sooner done than the balloon de- 
scended suddenly into the Adriatic, as before, and Zambeccari was 
rescued by some lishermen, though the balloon became a total loss. 
He finally attempted an ascent at Bologna in 1812. The balloon 
was blown by the wind against a tree, the spirit was upset, and the 
car again set on lire. He met his death by jumping from the 
balloon when it was at a distance of about 60 ft. from the ground. 

This constitutes the last appearance of " Rozieres " in the history 
of aeronautics, and though schemes of this kind have since been 
mooted, the danger attaching to work on these lines has always 
prevented any practical outcome. 



All investigations into the theory of the balloon rest upon the 
principle of Archimedes. Years before the birth of Christ he 
enunciated the following law. " Every body, which is immersed 
in a fluid, is acted upon by an upward force, exactly equal to the 
weight of the fluid, which is displaced by the immersed body." 
A result of this law is that a body will rest in any position, if 
immersed in a fluid of equal specific gravity ; if the body has a 
greater specific gravity than the fluid, it will sink, and on the 
other hand, if it has a less specific gravity, it will float. This 
law can be extended so as to apply to all gases, and a balloon will 
therefore rise in the air, if its total deadweight is less than that 
of the air which it displaces. 

A simple piece of apparatus is needed to show experimentally 
the truth of these assertions. Two spheres appear to have the 
same weight, when placed on an ordinary balance, the one being 
solid and the other hollow. If now the balance and the spheres 
are placed on the receiver of an air pump, and the air removed, 
the hollow sphere will appear to be the heavier. It is therefore 
evident that the hollow sphere is acted upon by a greater upward 
force when weighed in air than when weighed in a vacuum. The 
reason for this is very evident, when we consider that the 
weight of the gas displaced by the hollow sphere under the 
receiver of the air pump is much less than when it is weighed in 
the open air. It is therefore necessary to understand the 
properties of the air and of the gases used for filling balloons, 
before any adequate conception of the principles underlying 
their movements can be formed. 

The air may be looked upon as a mixture of 79 per cent, of 
nitrogen with 21 per cent, of oxygen. Gases have a tendency to 
diffuse themselves on all sides ; they have therefore great 


elasticity and can be easily compreBsed. The weight of a cubic 
foot of the atmosi»here at a temperature of 32° Fahr. and a 
pressure of 2!)'92 in. of mercury, is 0'0807 lb.; the weight of a 
cubic foot of hydrogen under the same conditions is only 
0'0O56 lb,, and of a cubic foot of coal gas about 0'04 lb. on an 
average. The law of Archimedes therefore states that a cubic 
foot of hydrogen will be acted upon by an upward force of 
0*0751. lb., and that the force acting on a cubic foot of coal gas 
will be similarly 0*0407 lb. Here we have assumed that the 

Fio. H, — The Bnroscopc. 

hydrogen is chemically pure. In point of fact, the above figures 
are slightly too high, in so far as ordinary samples of hydrogen 
and coal gas are concerned. 

But allowance must he made for the weight of the car, net, 
ropes, and other appurtenances, in calculating the effective 
upward force acting on the ballooti. It will therefore be evident 
that the size must be considerable if it is to he capable of rising 
in the air. The following example will perhaps make this clearer. 
Let us suppose that the weight of a balloon with its appurtenances 
is a quarter of a ton, and that its capacity is 21,000 cubic feet. The 
weight of the air displaced by it is 1,700 lbs., luui on the other hand, 
the weight of the containetl hydrogen is only 118 lbs. Consequently 



the net upward force is 1,022 lbs. If the expedition is to be 
undertaken at a moderately low level, thia force will probably be 
sufficient, and a reasonable number of passengers could be 
carried, together with instruments, maps, and a sufQciencj of 
ballast. But if it is intended to rise to great heights, things 
become very different. According to the latest results, the 
atmosphere is supposed to be about 125 miles high ; consequently 

balloon by Captnin 

the density and pressure of the air gradually decreases the higher 
we rise. The experiment which Toricelli carried out in 164S 
with a glass tube, about 3 ft. long, filled with mercury, is well 
known, and on the facts which he then discovered, the construc- 
tion of the barometer has been based. A mercury barometer is, 
however, very inconvenient tor the balloonist, and is very liable 
to be broken during the landing. The aneroid type ia therefore 
preferred. This consists of a very flexible metal tube, from the 
inside of which the air has been exhausted ; it istherefore more 
or less deformed by the external pressure of the atmosphere. A 


pointer on the front of the instrument is connected by an ingenious 
mechanism to the metal tube, and shows the amount of flexure 
or deformation which the tube has undergone at any moment. 
This pointer moves over a scale, and gives the pressure of the 
atmosphere in inches of mercury. Most of the aneroids, which are 
intended for aeronautical work, have a further graduation on the 
scale, showing the height, which is generally calculated with 
reference to some particular temperature, and is therefore liable 
to be very inaccurate. Hergesell gives a convenient formula 
which may be expressed as follows, viz. — 

, __ 52500 (P — p) (0-93 + 0-0022 1) 

- p+^, 

In this equation, h denotes the hei^^ht to be calculated in feet ; 
P is the barometric pressure at the earth's surface in inches of 
mercury ; j) is the pressure at the height h ; t is the mean tem- 
perature in degrees Fahrenheit. Suppose, then, that P is 80 in., 
p is 25J in., t is 48° Fahr. Substituting these values in the 
formula, it will be found that the height in question is 4,400 ft. 

The force with which the balloon is driven upwards will 
decrease as the pressure of the atmosphere decreases, seeing that 
the air which it displaces is less dense and therefore weighs less. 
The greater the atmospheric pressure, the greater will be the 
upward force. It will also be noticed, as a matter of experience, 
that the quantity of gas required by the balloon varies from day to 
day. Toricelli's experiments showed that the atmosphere exerts 
an average pressure equal to that of a column of mercury 
29*92 in. high ; the specific gravity of mercury is 13"59, and 
therefore the pressure of the air on a square inch is 14*706 lbs. 
Let us supix)se the air to be contained in a cylinder, which is 
closed by an airtight piston, the cross section of the cylinder 
being 1 square inch in area. Let us further suppose that this 
little piece of apparatus is placed beneath the receiver of the air 
pump. It will then be found that, if the piston is to be kept in 
position without allowing the gas in the cylinder to expand, it 
will be necessary to load it with a weight of 14*7 lbs. If the piston 
is loaded with a weight of 29*4 lbs., the volume of the gas will be 


reduced by one half ; the pressure of the gas will therefore be 
doubled, and its density similarly increased. Boyle and Mariotte 
have therefore stated that the volume of a gas is inversely 
proportional to its presBure or density. 
It is now possible with the aid of Boyle's law to calculate the 

"lift" which acts on a balloon at different heights, or with 
different atmospheric pressures. Let us suppose that the baro- 
metric pressure is that of 30 in. of mercury, and thiit the " lift " 
is 1,600 lbs. It the pressure sinks to 29 in., the lift will become 
^X of 1,600 lbs., i.e., 1,550 lbs. The difference l>etween these 
two forces is 50 lbs., and corresponds to the weight of iilwut two 
sacks of ballast. At a height of 6,fi00 ft. a cubic foot ot air 


weighs only 0*064 lb., and a cubic foot of hydrogen would weigh 
0*00396 lb. It is therefore possible in this way to determine the 
greatest height to which it is possible to ascend, if the dead- 
weight of the balloon is already known. 

Hitherto we have assumed the temperature to be constant, and 
it is necessary to examine the effect produced by its variation. 
The application of heat increases the volume of any gas. A 
simple experiment will make the matter plain. Take a glass 
tube, closed at the one end, and hold the open end below the 
surface of some water. If the glass tube is heated, it will be seen 
that bubbles escape through the water, owing to the expansion of 
the air within the tube. If it is then allowed to cool, the contrac- 
tion of the air still remaining in the tube will be made evident 
by the rise of water, which is sucked up to take the place of the 
retreating air, and Gay-Lussac has shown that all gases are equally 
expanded or contracted by the same variations of temperature. 

Finally, the diffusion of gases must be noticed. Let us suppose 
a closed vessel to be divided into compartments by means of a 
porous partition, and the two halves to be filled with different 
gases. It will be found after a time that the two gases have 
mixed completely with one another, even if the heavier gas 
should have been put in the lower half of the vessel. The speed 
with which the mixture takes place depends on the epecific 
gravities of the gases in question ; for instance, hydrogen will 
go more easily through a porous partition than coal gas or air. 
As a general rule, it may be said that the diffusion-velocities are 
inversely proportional to the square roots of the specific gravities 
of the gases. An obvious consequence of these facts is that the 
enclosed gas in a balloon is always escaping through the walls of 
the body, and being replaced by the intrusion of air. No 
substance can be used through which this diffusion does not take 
place, however carefully it is made in the first instance. Conse- 
quently the weight of the balloon is always gradually on the 
increase, while the lifting forces acting on it similarly decrease. 
A decrease of lifting force can only be met in one way, and that 
is by throwing out a certain amount of ballast. It is of course 
possible to calculate the amount which must be thrown away. 



bnt a little experience is far more useful than any amount of 

It will now be evident that a balloon which is meant for great 
heights must be of great size. In order to make a steady start 
it is usually loaded with as much ballast as it can conveniently 
carry, and this is gradually thrown overboard as the journey 
proceeds. In consequence of diffusion a certain amount of the 
gas-contents is always lost, such losses obviously depending on 
the extent to which the leaks have been repaired, and ballast 
must therefore be thrown out in order to counteract the effects 
of diffusion. It has also been pointed out that an increase of 
volume is caused by a rise of temperature. The heat of the 
sun will cause an increase of the volume of the contained gas, 
and unless it is allowed to escape the internal pressure will rise. 
On the other hand, a fall of temperature causes a contraction in 
the volume. In this case a smaller amount of air is displaced by 
the balloon, and the upward force acting on it is therefore 
decreased. This too must be counteracted by throwing away 
some ballast. If this were not done it would gradually sink to 
the ground, because the increased atmospheric pressure would 
tend still further to decrease its volume. It is therefore extremely 
important to determine this loss of weight with some exactness, 
and not to throw away ballast unnecessarily. The result usually 
produced, if the temperature is at all variable, is to take the 
balloon steadily higher and higher, and a cloudy day with 
intervals of sunshine makes a very unsatisfactory combination 
for the aeronaut, who is apt to find his ballast disappear all 
too soon. Another peculiarity is shown by a balloon that has 
not been completely filled. As it ascends the gas expands, and 
consequently displaces a larger volume of the surrounding 
atmosphere. This has the indirect effect of sending it still 
higher, until at last it becomes completely filled. Any excess of 
gas is then driven off and escapes, a position of equilibrium being 
reached. It will therefore be easy to understand why a balloon 
which has made a descent will again rise to a height at least 
equal to that from which it has fallen. 

It is now known that the heat of the sun will cause very 

A. D 


considerable variations of temperature within the balloon. This 
was first noticed by the brothers Robert during an ascent on 
September 19th, 1784, but it was not till much later that any 
exact measurements were made. Captain von Sigsfeld, who was 
fatally injured on the occasion of a descent at Antwerp in 1902, 
paid special attention to this matter, and concluded that the gases 
in a balloon might be heated to a temperature which was 80° or 
90° Fahr. above that of the surrounding atmosphere. The e£Fect 
of this on the " lift " will be evident when it is remembered that 
a difference of temperature of 1° Fahr. alters the weight of a 
cubic foot of coal gas by O'OOll oz., and of hydrogen by 
0*00016 oz. A balloon filled with hydrogen is much less affected 
by changes of temperature than it would be if filled with coal gas, 
and is therefore much simpler to manoeuvre, especially at night 
time. It is also important to notice any tendency on the part of 
the balloon to sink. Otherwise, if it is only noticed after the 
sinking has continued for some time, it will be necessary to 
throw overboard a large amount of ballast, and the balloon may 
eventually rise to a much greater height than that from which it 
had fallen. A further trouble arises it the sinking is not noticed 
at an early stage, as the neck through which the gas is passed 
into the balloon at the bottom is usually left open, or in any case 
is only slightly closed. A descent causes a contraction in the 
volume, and there is a tendency for the air to enter by the neck. 
It then mixes with the gas, and as soon as the balloon rises 
again some of the mixture of air and hydrogen escapes, leaving 
the balloon in a less buoyant condition than it was before the 
sinking began. 

It is therefore a matter of great importance to be able to detect 
at once any tendency to fall. For this purpose the most useful 
auxiliary is the barometer, more particularly one of the recording 
type. But such instruments are often sluggish in their move- 
ments, and fail altogether to show very slight variations. Even 
a very marked variation is often only shown after it has been in 
progress for some time, but to some extent this sluggishness may 
be avoided by gently tapping the instrument from time to time. 
These disadvantages have led to the development of instruments 



which show at a glance aoy change of elevation. Of these, the 
so-called statoscope, made by Gradenwiiz, may be taken as a 
type. It is contained in a metal ease, somewhat similar to that 
of a watch. Beneath the face is a circular opening, into which a 
tightly-stretched rubber membrane is fitted, and a small rubber 
tube communicates with the inside of the case. If now the rubber 
tube is pinched, the outer air can no longer freely reach the 
inside of the case. Supposing the balloon to he ascending, the 
air enclosed within the stato- 
scope will therefore expand, in 
consequence of the reduced 
external pressure ; if it is de- 
scending, the optjosite effect 
will take place. The contrac- 
tion or expansion of the en- 
closed air reacts on the rubber 
membrane, which will be 
sucked inwards during a de- 
scent, and blown outwards if 
the balloon is rising. The 
movements of the membrane 
are communicated by very 
delicate wheelwork to a pointer 
on the face of the case, which 
therefore shows at a glance whether a rising or falling movement 
is in progress. 

It is not always necessary to throw out ballast in the case 
of a momentary descent. The movements of overhead breezes 
do not usually take place in straight lines, but rather partake 
of the nature of wave motion. A balloon which is in a state 
of equilibrium usually follows a path of this sort. Under such 
circumstances one would merely be wasting ballast if it were 
thrown overboard to counteract a fall ; with a little patience, it 
would soon be found that the balloon rises again of its own 
accord. It is therefore rather a matter of determining the 
relative motion between the aeronaut and the surrounding 
atmosphere, and for this purpose von Sigsfeld has devised the 

D 2 



following simple method. Three different kinds of coloured 
papers are torn up into small pieces, the various papers having 
different thicknesses. Consequently each piece of paper begins 
to fall at a particular rate, which is known by its colour. For 
instance, let us suppose that the white paper falls at the start 
with a velocity of 18 in. per second, the blue at the rate of 3 ft. 
and the red at the rate of 6 ft. per second. By throwing out 
a handful of these papers, ifc is possible to tell at once what is 
the vertical movement. If the white pieces remain on a level 
with the balloon, then a fall is in progress at the rate of 
18 in. per second. If all the pieces rise above the balloon, then 
the descent is more rapid than 6 ft. per second; if they all 
disappear below, then the balloon is either rising or at rest. 
Suppose that the barometer shows an increase of pressure, and 
at the same time it is noticed that the white pieces of paper 
remain on a level with the car; it will then be seen at once 
that the balloon has been caught by a descending breeze, 
because otherwise the great mass of the balloon would cause a 
much quicker descent. In this case, the ballast can be saved. 
The pieces of paper are also useful as an indication of the amount 
of ballast which it is necessary to throw overboard in any 
particular case, as much may be learnt by noting their apparent 
velocity. A simpler and more primitive method is to hang a 
feather at the end of a kind of fishing-rod over the side of the 
car. If there is no relative motion between the balloon and the 
surrounding air, the feather will remain at rest ; otherwise it will 
rise or fall, and the deduction is obvious in either case. When 
a descent is noticed ballast must be thrown overboard; and 
though there is no precise indication of the moment whe)i the 
operation can be stopped, the gradual sinking of the feather will 
show when the mark has been overshot. A further sign that 
may be noticed is given by the formation of folds on the body of 
the balloon, or by the collapse of the neck through which the gas 
is passed. We shall later have occasion to study the effect of 
meteorological conditions on ballooning, but for the moment we 
propose to consider in the following chapters the history and 
development of the dirigible balloon. 



The eager restlessness of the human mind is well shown in 
the early history of ballooning. Long before the first practical 
successes were properly understood, countless suggestions were 
made on all sides with the object of constructing an airship 
w^hich should be under control in so far as the direction of its 
motion was concerned. Many machines were actually built ; but 
the number of suggestions was out of all proportion to their 
value. No idea seems to be too foolish to prevent it from 
being used by a succession of inventors, and it may be said 
that all the good and bad points of modern construction have 
been already used in some form or another in bygone ages. 
We are, however, little better than our ancestors. The most 
idiotic suggestions, which ever entered the mind of man, con- 
tinue to arrive daily by post, until finally one ceases to be 
surprised at anything. 

The Persian myth, according to which the King was presented 
with a throne harnessed to eagles, has been already mentioned, 
and it is rather amusing to find that an Austrian, named Eaiserer, 
published a treatise in 1801, entitled '* A new method of steering 
balloons by means of eagles." Even nowadays the idea does not 
seem dead and buried, for in 1899 a German presented the 
Kaiser with a copy of a book, wherein he propounds a solution of 
the problem, which consists in harnessing a large number of 
pigeons to the balloon. His drawings showed the scheme carried 
out to the minutest detail, even including the reins, bridles and 
bits, proving him at any rate to be an expert on paper. It is a 
fact that a German patent was granted for this invention. 
Another absurd idea, which arose in the eighties, was to construct 
a balloon of such a size that it could rise to a height where it 
would no longer be acted on by the force of gravity, in which 



case a sail round the earth ivould be, at the outside, a matter of 
twenty-four hours. 

It is now proposed to take a chronological survey of the 
development of dirigible balloons and flying machines, and to 
mention even some of those that did not directly lead to a 
successful issue. Many have contributed towards a solution of 
the problem, but it must at the same time be acknowledged that 
the progress, which was made in the course of some 120 years, 
was extremely small. 

The first idea was taken from ships, and consisted in attempts 
to guide the baUoon by means of sails, oars and rudder. Joseph 
Montgolfier showed much sense when he described this scheme, 
in a letter to his brother, as absurd. He pointed out that even 
if a number of men were to work something of the nature of 
oars, it would only be possible in perfectly calm weather to move 
at the rate of four or five miles an hour. In this connection it 
is necessary to bear in mind the small surface which can be 
exposed by the oars to the air, and to remember that the air 
offers an immense resistance to the motion of the balloon, in 
consequence of its enormous size. The only way to compensate 
for the smallness of the oars would be to move them very fast 
and to suitably design the shape of the balloon, and of the oars. 
But there is a limit to human effort, and since the resistance of 
the air increases with the square of the velocity, it soon becomes 
evident that even in gentle breezes the only method of over- 
coming the resistance would be by means of propellers, driven 
at high speeds. The effect produced by rudders is similar to 
that produced by them on ships, always supposing the balloon is 
under weigh. The proposals to use vertical sails betray a 
complete misconception of the laws underlying the movements 
of balloons. If a balloon, filled with gas, floats in the air, all its 
parts will move with the breeze, and at the same speed. A sail 
would therefore hang just as limply as it would do in a complete 
calm. It would be different if it were possible to give the balloon 
a smaller or greater velocity than the wind, and in such a case 
a pressure would be exerted on the sail. The explorer Andree 
proposed to work on this idea in the simplest fashion. He 


Fl(i. 19. — Italloon with Bail, anJ ivitli |5uidc-roj>i! fnslonod to the ring. 

intended, with the help of the friction cauHed by a Dumber of 
ropes dragged along the ground, to cause the balloon to go rather 
Blower than the wind. A sail was then to be hung out, and 


placed in each s position that the force of the wind acting on it 
would drive the balloon in any desired direction. Tests have 
shown that with clever management it is possible to produce in 
this way a slight deviation from the direction of the wind. It is 
also known that surfaces slightly inclined to the horizontal will 
produce a slight movement of the balloon as it riBes and falls. 
Stephen Montgolfier knew this and tried to utilise the idea in 
one of his models. Since his time many others have also 
worked on the same lines, but no practical success has been 

In the year 188S, Professor Wellner, of Brunn, published his 
scheme for the construction of a sailing balloon. Seeing that 

surfaces inclined to the horizontal have a slight lateral motion 
as they fall or rise, he thought that by alternately raising and 
lowering such surfaces he would be able to move in any desired 
direction, and to produce the necessary verlical movements hy 
increasing or decreasing the internal beat of the balloon. His 
calculations tended to show that a " fish-balloon," 150 ft. long, 
and 50 ft. in diameter, having a verlical surface in front and a 
horizontal one behind, might reach a speed of 10 miles nn hour. 
As a matter of fact, his tests in Briinn showed that a single rise 
and fall moved the balloon over a distance of 3 miles in a 
direction opposed to that of the wind. There is no doubt as to 
tlie correctness of the mechanical principles involved, and 
Lebaudy has also worked on the same ideas, usinj; several 
surfaces whose inclinations can be altered. 
Guyot built the first sailing balloon in 1784, and naturally it 


was unsuccessful. The only noteworthy point about his design 
was that the body of the balloon was made of the shape of an 
egg ; the longer axis was horizontal, and the flatter end was at 
the front. Gradually it was recognised that any system which 
involved propulsion by oars was likely to be inadequate. Carra 
proposed to use paddle-wheels, which were to be mounted on a 
shaft, projecting over the sides of the car. This certainly was a 
move in the right direction, but even so the improvement was 
only slight. The effect produced by the shape of the balloon on 
the air-resistance was soon noticed, and they were consequently 
made rather longer than before. A start was made by the 
Academy of Dijon, who placed the matter in the hands of Guyton 
de Morveau. The front was to be wedge-shaped, so as to allow 
the air to pass lightly over it, while the steering was to be done 
by means of a vertical sail hoisted at the other end. This 
method of steering is still in use at the present day, and has 
been found to work well. Still the construction, which was 
proposed by the Academy, met with no success. It included a 
scheme for working with oars, in combination with a sail, which 
could be raised or lowered about a horizontal axis. Naturally 
it was found that forces of this order were much too small. 
Countless proposals of this kind were made in rapid succession, 
but all employed the same means of propulsion, and met with 
the same fate. 

The Montgolfih'eSy made by the priests MioUan and Janinet, 
were ingenious novelties. The balloon w^as to be 92 ft. broad 
and 106 ft. high, and according to an idea due to Joseph 
Montgolfier, it was to be driven forward as the result of the 
reaction produced by the escape of the hot gases. An opening, 
14 in. in diameter, was therefore made in the middle of the balloon, 
and through this hole the hot gases were to escape, a fire being 
maintained, as usual, in the pan which was carried on the car. 
A further series of improvements occupied some time, until at 
last the exasperated mob, thinking that the start was likely to 
be postponed indefinitely, destroyed the whole concern. 

The effect produced by the egcaje of gases and fluids is well 
known, [and Barker's mill, which is nowadays used for watering 


grass lawns, is a familiar example of a reaction turbine. The 
idea, as applied to the propulsion of balloons, is still a popular 
one ; perhaps the most ridiculous form in which it has been 
expressed is to be found in the proposal to carry small cannons 
on the balloon, in the hope that the recoil would expend itself 
in driving it forwards. 

General Meusnier introduced a great improvement by proposing 
the use of air-bags, to be carried inside the balloon. The air- 
bag plays even yet a considerable part in the working of captive 
and dirigible balloons. The first attempt that was made to test 
this idea on a practical scale nearly ended fatally. The brothers 
Robert, whose names have been already mentioned, placed the 
air-bag close to the opening by which any excess of gas was 
allowed to escape. It so happened that as they rose they came 
into a violent eddy, which tore away their oars and rudder, and 
broke the ropes which held the air-bag inside the balloon. An 
unfortunate result was that the opening became stopped up, and 
the gases, which expanded considerably on account of the ascent, 
were unable to escape. At a height of 16,000 ft. the Duke of 
Chartres, who was in the car, had the presence of mind to cut a 
hole in the balloon 10 ft. long with his sword. It was on the 
point of bursting, but now began to sink rapidly, and by throwing 
out a suflScient amount of ballast, they were able to reach the 
ground without injury. Although it seems obvious that the 
Duke's action saved the situation, his supposed lack of courage 
was the subject of much ridicule. 

It may be useful to describe more exactly the design which 
was due to Meusnier, more especially seeing that he may be 
regarded as being to a great extent the forerunner of the modern 
inventor. He had great scientific and technical knowledge, 
and went very carefully into the question, basing his schemes 
throughout on the results of experimental work. In the first 
instance he studied questions relating to the resistance of the air, 
and the shapes which were likely to offer the least resistance. 
He found that an elliptical shape was the best, and in order still 
further to reduce the resistance, he proposed to use a boat-shaped 
car, pointing in the direction of motion. He was the first to 


state that an absolutely rigid connection between the car and 
the body of the balloon was an indispensable feature of a 
dirigible machine. Even if the moving parts were to be housed 
beneath the main body, they would necessarily be driven from 
the car, and a rigid means of connection would therefore be 
required. He used three propellers, which were supported mid- 
way between the car and the body, and these were to be driven 
by hand by means of pulleys. He well understood that the 
result produced by one man would be very small, and calculated 
that a crew of eighty would be required. At that time no other 
form of motive power was available. 

He also made careful investigations into the matter of gas 
pressure, and by means of specially constructed models was able 
to determine the exact force exerted on the envelope. His plan 
also included the use of horizontal surfaces to increase the 
stability, and this certainly foreshadows Lebaudy's inventions. 
In addition, special arrangements were made to prevent the car 
from sinking, in case an accident should plunge the balloon into 
the sea. 

But Meusnier's most important improvement is the use of the 
air-bag, and this must be more fully described on account of its 
importance. In his original memoir he described the object and 
construction of a " special space, intended to enclose atmospheric 
air." The importance of this arrangement lies in the possibility 
of preserving the shape of the dirigible balloon. Every inventor 
desires to reduce the resistance of the air to a minimum, and it is 
therefore necessary that the balloon should retain a definite shape. 
If the envelope were rigid, the matter would be simple enough ; but 
we know that changes of temperature and external pressure cause 
corresponding changes in the volume. An increase of internal 
pressure can be relieved by an automatic valve, but a contraction 
is at once noticed by the creases on the envelope. No doubt any 
decrease in volume can be met by pumping air into the balloon ; 
but this naturally dilutes the pas, besides gradually creating a 
very explosive mixture. The best plan would be to pass more 
gas into the balloon ; but owing to the weight of the cylinders 
used for storage, it is impossible to take compressed gases on a 


journey, though some method of storing gas in a liquid form may 
in the future be available. Tbe use of air-bags is therefore the 
only solution ; wlieu the volume of the envelope tends to increase, 
the air is pressed out of the receivers, and when it contracts air 
is sucked in. These air-bags can be mounted in tbe balloon 
in three different ways. According to the first method, the 
envelope is made with two coverings over a portion of its length. 

Kio. 21.— Balloon, deaiKied l>y General Meuanifr. 
Tlie two coverings lie tightly one upon the other when the 
balloon is full. But with a view to avoiding any unnecessary 
loss of gas, it is better to fill the outer space with a certain 
amount of air at the start, so that the volume of enclosed air 
corresponds to the increased bulk at the desired height. The 
valve will, therefore, only be opened when the balloon has risen 
to the proper level. The most ordinary method consists in 
simply putting air-bags inside the balloon. Their size depends 
on the height to which it is intended to rise, seeing that this 
determines the amount the balloon will expand. Such air-bags 


were used by the brothers Robert on the occasion of their 
ascent with the Duke of Chartres. The third method consists in 
having two separate envelopes, the inner one containing gas, 
and the space between the inner and outer ones being filled 
with air. Meusnier himself proposed the last form of con- 

But the air-bag is also used to serve other purposes. Meusnier 
intended to compress the air contained in it, and in this way to 
keep his balloon in a position of equilibrium. To a certain 
extent this is possible ; but the envelope is not capable of resist- 
ing any great pressure, and of late years this idea has been given 
up. But it has a more important use in regulating the height 
to which the balloon ascends. By compressing the air contained 
in it, the weight can be increased, and the balloon consequently 
sinks. The amount of gas which can be saved by these means 
in the case of a dirigible balloon is considerable. It is also 
possible to prevent the balloon from rising by the same method. 
Lebaudy was able to pump air at the rate of 85 cubic feet per 
second, and in spite of the fact that he threw overboard some of 
his ballast, he was able in a few seconds to make good the loss 
with the aid of his pumps. Meusnier's idea was to carry bellows 
on the car, and to work them by hand. He also proposed to have 
a third covering outside his balloon, and to bind it on with 
network, which was to be fastened to the car by means of 
ropes. His anchor was of a peculiar shape, consisting of 
a kind of harpoon, which was intended to bury itself in the 

Meusnier's scheme was the best that had been worked out by 
a single individual up to that time ; its probable cost, however, 
prevented it from being carried into execution. He was killed, 
fighting against the Prussians at Mayence, 1793. When the 
news of his death reached the King of Prussia, he ordered the 
firing to cease until Meusnier's body had been buried. After 
this time interest in the matter of dirigible balloons gradually 
waned, because it was recognised that the only driving power 
that was then known was wholly insufficient to meet the 
requirements of the case. So that after 1786, ballooning fell 


almost entirely into the hands of country showmen, who adver- 
tised excursions, and attracted attention in a variety of other 
ways. It cannot be said that there was an entire dearth of 
schemes relating to dirigible balloons, but at any rate nothing 
worthy of mention was published before the year 1852. The 
first half of the nineteenth century can therefore be passed over 
in silence. 



The development of the dirigible balloon dates from the year 
1852, when Giffard appeared on the scene. He subsequently 
invented the injector for steam boilers, and was already well 
known in the aeronautical world, having made ascents with 

Eugene Godard. In 
1851 he succeeded in 
making a small steam 
engine of 5 h.p., which 
only weighed 100 lbs., 
and thought it might be 
useful in connection 
with balloon work. With 
the help of two of his 
friends, he built an air- 
ship, which was some- 
what of the shape of a 
cigar with pointed ends. 
It was 144 ft. long, 
40 ft. in diameter at the 
thickest part, and its 
capacity was 88,000 
cubic feet. The envelope 
was covered with a net, 
and a heavy pole, 66 ft. long, was carried below, being suspended 
in a horizontal position by means of ropes which connected it to 
the net. At the end of this keel, as Giffard called it, the rudder 
was placed, which took the form of a triangular sail. The car 
was carried below the pole at a distance of 20 ft., and contained 
the motor and propellers. The 8 h.p. motor together with its 
boiler weighed 850 lbs., and drove a three-bladed propeller, 11 ft. 

Fig. 22.- 

-Giffard's dirigible baUoon, made in 



in diameter, at the rate of 110 revolutions per minute. The total 
weight of the balloon, together with that of one passenger^ 
amounted to 1^ ton, and it was reckoned that, when filled with 
gas, it could carry | ton of coal and water. In the light of 
subsequent experience it is evident that the weight of the steam 
engine was too great, having regard to the effect which it was 
able to produce. Giffard himself saw this, but calculated that 
he would be able to attain a speed of 6 or 8 ft. a second. On one 
occasion this result was actually produced. 

We must now examine the question of speed, and ascertain its 
value under ordinary working conditions. In other words, we 
must find out what speed it is reasonable to expect from a balloon 
that is to be used on and off the whole year round. Meteorological 
observations show that in Europe a balloon can move with a speed 
of 40 ft. per second on about 82 per cent, of the days in the year, 
and with a speed of 45 ft. on 90 per cent. This must of course 
be capable of being maintained for several hours. If the balloon 
has a speed due to its own internal energy of 40 ft. a second 
then it would be able to move at the rate of 8 ft. per second 
against a wind blowing at 87 ft. per second. It would thus have 
a resultant speed of two miles an hour, which seems no great 
achievement. But then it must be remembered that in stormy 
weather a sailing ship would remain in the harbour, and is only 
able to make headway against the wind by tacking. Moreover^ 
the course of a balloon would not always be steadily in a direction 
opposed to that of the wind. Complaints are often made that a 
balloon caught in a storm is sometimes completely destroyed. 
But an aeronaut must be something of a meteorologist, and he 
ought to be able to form an opinion as to whether he is likely to 
encounter any serious storm. Naturally balloons are no more 
likely to escape the effects of rough weather than sailing ships. 

After this short digression we can now return to the further 
consideration of Giffard's arrangements. He had a special con- 
trivance to prevent the possibility of any explosion resulting from 
the escaping gases of the balloon. He placed a piece of wire gauze, 
similar to that used in safety lanterns, in front of the stokehole, 
and the gases from the boiler were taken to one corner of the car 

A. E 


and discharged below. These precautions were very important, 
and it was only due to ignorance of these matters that Wolfert 
and Bevero lost their lives in later years. In 1855 Giffard pro- 
duced a second balloon, which he had mode narrower and longer 
with a view of diminishing the ait-reaiBtance. It was 33 ft. in 
diameter at the middle, and 230 ft. long, having a capacity of 
113,000 cubic feet. He stiffened the apper part of the envelope 
with a special covering, to which the net was secured. The car 
was suspended by ropes, which were attached to its four comers. 
He used the same engine as before, but the chimney was simply 
taken to the aide of the car and bent over at right angles, 
explosions being avoided by placing the car rather lower. In 
company with a manufacturer, named Yon, he made a trial trip and 
succeeded in moving 
slowly against the wind. 
When the descent began, 
owing to some accident 
the horizontal axis tilted 
up, the weight of the car 
broke the net from its 
moorings, and the bal- 
loon was completely 
destroyed, the occupants escaping with slight injuries. No air- 
bags were used, and this accounted for the accident. 

Gififard now planned a third balloon, which was to be 1,970 ft. 
long, and 98 ft. in diameter at the middle. Its capacity was to 
he 7,800,000 cubic feet ; the motor was to weigh 30 tons, and the 
speed to he 60 ft. per second. The immense cost of this scheme 
prevented it from being carried into execution, and Giffard then 
devoted his attention to the design of small engines. His subse- 
quent invention ot the injector put him once more in a position to 
renew his work. In 18ft8 he made a captive balloon for the exhi- 
bition in London ; its capacity was 424,000 cubic feet, and its cost 
nearly i'SO.OOO. A similar one was made in Paris in 1878, having 
a capacity of 883,000 cubic feet. In addition to all this, a dirigible 
balloon was designed, holding 1,750,000 cubic feet, which was to be 
fitted with two boilers, and to cost ^40,000. Tiiis scheme was 


thoroughly worked out in every detail, but was never carried into 
ex^ution. Giifard subsequently became blind, and died in 1882. 

Nothing further was done till the siege of Paris. The French 
Government then commissioned Dupuy de Lome to build a diri- 
gible balloon, which, however, was only tested after the war in 
1872. It is curious to find that this man, who was a marine 
engineer and therefore professionally acquainted with problems 
of this kind, proposed to employ a crew of eight men in driving 
the propeller. His method of construction was ingenious, and 
he succeeded in reaching a speed of 9 ft. a second, which was 
about the same as GifTard had done. His balloon had a eigar- 
shaped body ; its length was 116 ft., 
its greatest diameter was 49 ft., and 
its capacity 122,000 cubic feet. The 
form which was given to the net 
was peculiar, and intended to prevent 
any displacement of the car, relatively 
to the body of the balloon, which 
might otherwise be caused by the 
working of the propellers. For this 
purpose some of the ropes were crossed 
in the space between the car and the 
body, whereas the others were taken direct to the sides of the 
car, which was built in the shape of a boat. It carried 14 men, 
who worked the propeller, and also attended to the pumps used 
in connection with the air-bags. It is hardly necessary to give 
any further description of this scheme, seeing that it constitutes 
nothing of the nature of an advance on its predecessors. 

In the meantime, Paul Haenlein (who died in 1895) constructed 
an airship in Germany. Its shape was that of a solid formed by 
the revolution of a ship's keel about an axis lying on the deck. 
C!areful hydrostatic experiments led him to the choice of this 
curious shape, which in the middle is more or less cylindrical, 
and at the ends somewhat conical. Its length was 164 ft., the 
greatest diameter 30 ft., and the capacity 85,000 cubic feet. The 
car was placed close to the body, in order that the parts might 
he as rigidly connected as possible. I'or the first time in the 



history of aeronantiicB it was proposed to ase a gas engine, which 
was of the Lenoir type, and had four horizontal cyHndars, giving 
6 h.-p., with an hourly consumption of 250 cubic feet of gas. The 
gas for the engine was taken from the balloon itself, and the 
loss was to be made good by blowing out the air-bags. The car 
was made of beams running lengthwise, and was supported 
tangentially by ropes from the network. The envelope was 
made airtight by a thick coating of rubber on the inside, backed 
by a thinner one on the outside. Being filled with coal gas it 

Fia. 25. — Paul fiaenlein's dirigible balloon. 

could not ascend to great heights, and the trials were therefore 
undertaken at a short distance from the ground, the balloon 
being kept in the captive state by ropes loosely held by soldiers. 
It attained a speed of 15 ft. per second, and this is an improve- 
ment of 6 ft. per second on the attempts of Dupuy de Lome. 
Lack of funds prevented any further attempts from being made, 
and though the project promised well and had some notable 
improvements, it was unable to proceed further. If Haenlein'a 
results are compared with those of Lebaudy, who has reached a 
speed of 40 ft. per second, we can hardly doubt he would have 
achieved more if he had filled his balloon with hydrogen, and if 
light motors, of the type now in use, had then been available. 



Ten years later the brotbers Gaeton and Albert Tiaeandier 
produced a remarkable airship. Daring the Franco- Prussian war, 
Gaston TiBBandiermademanyiuiBnceeaBful attempts to enter Paris 
by means of a balloon while it was in a state of siege. A model was 
shown during the Exhibition of 1881, and they were encouraged to 
proceed on a larger scale. The body was shaped, after Gifbrd's 
model, somewhat like a 
cigar. It was 92 ft. long, 
30 ft. in diameter at the 
middle, and had a capacity 
of 37,500 cubic feet. It 
was made of varnished 
cambric. The car was la 
the form of a cage, con- 
structed of bamboo rods, 
and contained a Siemens 
dynamo, together with 
24 bichromate cells, each 
weighing 17 lbs. At full 
speed the dynamo made 
180 revolutions per 
minute and the pull was 
26 lbs. When the tests 
were undertaken it was 
found that a speed of 9 or 10 ft. per second was attained, 
when the motor gave 1^ h.-p. It cost £2,000, but there was 
nothing remarkable about the construction. 

ISo little success bad attended the construction of dirigible 
balloons that it was gradually being regarded as likely to be 
impossible. Great astonishment was therefore caused in 1884 



by the announcement that two French officers, named Benard 
and Krebs, had [described a figure of 8 in a balloon, and had 
returned to the point from which they had started, Charles 
Kenard had been studying the problem since 1878 with the 
assistance of one of his friends, named La Haye, and had 
boped with tlie help of Colonel Laussedat, who commanded 
the Engineers, to obtain the necessary funds from the 
Minister of War. It was then pointed out that large sums of 
money had been wasted on similar projects in 1870, and their 
request was consequently refused. They therefore had recourse 
to Gambetta, who was much interested, and promised a sum of 
it8,000. In the meantime, La Haye had been succeeded by 
Captain Erebs, and with the help of the latter Renard proceeded 
with the work. The air- 
ship was of the shape 
of a torpedo, and was 
slightly larger in diameter 
at the front than at the 
baeli. It was 165 ft. long, 
and rather more than '2,7 
ft. in diameter at tlte 
biggest part, and had a 
capacity of 66,000 feet. 
The car which was con- 
structed of bamboo rods, was 108 ft. long, 6 ft. high, and 4J ft. 
broad, being covered on the outside with silk. An electric 
motor, capable of giving 85 h.-p., was driven by an accumu- 
lator, and connected to a propeller, which was carried at the 
front, and made of wooden beams 23 ft. long. In order to 
prevent any injury to the propeller blades when a descent was 
made it was possible to slightly raise the aiiis on which they 
were mounted. Moreover, Kenard intended to obviate any 
serious shoclts on coming to earth by using a guide rope. The 
way in which such a rope is used becomes evident it the arrange- 
ments made for a descent are considered. Suppose a balloon to 
l>e falling. It will gradually reach a considerable velocity, unless 
measures are taken to prevent it. and a violent shock would 

Fig. 27.— Tisfandier's dirigible balli 


result from contact with the ground. It is, however, diflBcult to 
check this velocity by throwing out ballast, because the throwing 
out of too little ballast might not be sufficient to -prevent a 
dangerous shock, and if too much were thrown out the balloon 
might begin to ascend. The following plan is therefore adopted. 
A heavy guide rope, from 200 to 800 ft. long, is gradually paid 
out shortly before the car reaches the ground. This corresponds 
to so much ballast, and the shock is consequently very much 
reduced. If for any reason the balloon begins to ascend again, 
it drags with it some of the rope, and this increase of load tends 
to bring it down again. Automatic reactions of this kind play 
an important part in bringing a balloon to the ground, or in 
travelling at a low level. The friction of the rope against the 
ground is also useful in checking the speed, and allows an anchor 
more time to fasten itself. Renard also carried a so-called 
** sliding-weight," and this could be moved into any suitable 
position so as to counteract any shifting of the centre of gravity 
that might be caused by movements of the passengers. The 
total weight, together with ballast, was 2 tons. At the back 
between the car and the body of the balloon a rudder was 
mounted, which was rectangular in appearance, and trapezoidal 
in cross-section ; any distortion of its shape was therefore 
impossible. It was moved about a vertical axis by means of ropes, 
which were secured to beams projecting over the sides of the car. 
The inventors waited nearly two months in perfectly calm 
weather, but at last, at 4 o'clock in the afternoon of August 9th, 
Renard and Krebs mounted the balloon, which they called " La 
France,'* and made an ascent. As soon as they had risen above 
the level of the trees in the neighbourhood of Chalais, they set 
the propellers in motion. Immediately they noticed that the 
speed was increasing, and as a further encouraging symptom it 
was seen that small changes of direction could be effected by 
means of the rudder. The journey was therefore continued from 
north to south till they crossed the road from Choisy to Versailles, 
after which they turned to the west. It had not been intended 
to sail directly against the wind, which however only amounted 
to -a gentle breeze. But their confidence increased, and at a 



distance of 2^ milea from Ghalais they turned round, completing 
the bend in the Bmall angle of 11 degrees at a radius of about 
160 yards. After a slight deviation to the right-hand side, which 
waB soon corrected by the rudder, the balloon reached a spot 
1,000 ft. above the starting point. The valve was slightly opened, 
and the balloon was then manoeuvred by means of the motor 
into the most convenient spot for the descent, which was about 
80 yards above the parade ground. The guide rope was caught 

Fio. 28.— Tlie balloon " La France," built bj Rtnaitl and Krcb«. 

by the soldiers, and the balloon was safely landed, after having 
covered rather less than 5 miles in 23 minutes. 

A second expediiioii was less suceessful. The wind was rather 
stronger, and drove the balloon before it. The arrangements 
connected with the motor were injured, and a descent had to be 
made at a distance o( 3 miles from the starting point. The 
balloon was then carried back to Chalais. On the third occasion 
the course was directed N.N.E. against the wind towards 
Billancourt. In order to determine the velocity of the wind, 
Keiiard stopped llie motor and let the balloon drift. He then 
found that the wind was blowing at the rate of 5 miles an hour, 
i.e., 7 ft. per second, wliile the velocity due to the motor was 
IJ S miles an hour, or 7 yanis per second. The balloon was then 
brought to land at the starting point. Out of seven attempts it 


vi&B possible to bring the balloon back to the starting point on 
five occasions. At the fifth attempt the wind was blowing with 
a velocity of 21 ft. per second, and it was consequently 
impossible to sail in the opposite direction. The sixth and 
seventh journeys were made to the city of Paris. It was there- 
fore clearly demonstrated to all unbelievers that the dirigible 
balloon was now within the range of practical possibilities. In 
spite of its snecesses, the French have not adopted this type, 
partly because its speed was insufficient, and partly because it 
could only undertake a short 
journey. Renard made further 
attempts to construct one on a 
bigger scale, bat tbey were 

In 1879 Baumgarten and 
Wolfert built a balloon in Ger- 
many that was fitted with a 
Daimler benzine motor, and the 
first ascent was made with it at 
Leipsic in 1880. It had a pro- 
peller for raising it in the air, 
and was fitted at the sides with 
things of the nature of wings, 
which were for the purpose of 
producing horizontal motion. Fia. 29.-C«ptam Iteuard. 

Baumgarten almost came to grief during the first trial. The 
airship had three cars, and the result of carrying a passenger 
in one of the outer cars was that the load was unevenly 
distributed. In consequence the whole thing lilted over with 
the longer aiis in a vertical position, and came with a crash 
to the ground. The occupants luckily escaped without injury. 
Baumgarten subsequently died, and Wolfert proceeded with 
the work alone. Successful experiments were said to have 
been made, and finally it was arranged to make an ascent on the 
Tempelhofer Feld, near Berlin, on June 12th, 1897. The 
balloon rose to a height of 600 feet and travelled with the wind. 
Suddenly a fiame was seen to dart from the motor towards the 



main body of the balloon, a slight, report wa9 heard, and the 
whole thing fell to the ground, where it waa entirely destroyed 
by the flames before it was possible to rescue Wolfert and his 
companion. The disaster was caused by the fact that no suitable 
precautions were taken in connection with the benzine vapour, 
which formed an explosive mixture with the air, and was 
accidentally filed. One would have thought an accident of this 

kind was suliieient to put inventors on their guard, and it is 
therefore strange to find that Sevei'o'a death was caused a few 
years later liy precisely the same defect in hiw arningementB, 

An Austriiui engineer, named Scliwarz, made a balloon with a 
rigid envelope, but the ascent on the Tempelliofer Feld in 1897 
was iinsuccesfiful. Jliirey Monge and Dupuis Deleourt had 
already proposed in 1831 and 184-1 to construct the body of metal 
and this was actually done. But their efforts failed in conse- 
quence of the iiisulhcient rigidity of their design and the leaks 


wliieh occurred at the jointe. Sehwarz'a balloon was constiucted 
of aluminium, O'OOS in. thick, which was supported on a stiff 
lattice-work, made of tubes of the same metal. The shape was 
peculiar, but it was probably owing to difGculties of construction 
that it was impossilile to use the form, which had been already 
found, as the result of many experiments, to offer the least 
resistance to the air. The ascent was undertaken by a soldier 
out of the Balloon Corps, and he was driven in the direction of the 
wind. The belts driving the propellers came off their pulleys, 
one after another, and in consequence ot serious leaks the 

Via. 31. — (^chwarz'ji ballain atlcr the acddenl. 
balloon came to the ground in a short time at a distance of 4 
miles from the starting point. Great injury was done by the 
shock on coming to earth, but the soldier escaped by jumping 
from the car before it reached the ground. Soon afterwards it 
was completely destroyed by the wind. 

The way in which rigid bodies of this type are filled with gas 
must be here described. It is not possible to pass the gus 
directly into the balloon, as this would merely cause a mixture 
of air and gas. Schwarz's balloon was 156 ft. long, and con- 
tained 130,000 cubic feet. It was filled by Captain von Sigsfeld, 
who passed a number of bags into the balloon, and inflated 
them with gas. After it was filled the bags were pulled to 
pieces and torn out again. Another method consists in placing 


a linen envelope within the aluminium casing. This linen 
envelope is first blown out with air, and the gas is then passed 
between the aluminium and the linen. The air is therefore 
gradually pressed out of the linen envelope, which is withdrawn 
at. the end of the operation. It may be well to mention two 
methods which are unsatisfactory in practice. The one con- 
sists in passing steam into the body of the balloon, which 
condenses while the gas is passed in, and flows away in the form 
of water. The other consists in passing the gas while the balloon 
is submerged under water. In any case, under the most favour- 
able conditions, it is a tedious and delicate operation. 

If we glance back at the progress which has been described in 
this chapter it will probably seem as though little had really been 
done in these forty-five years. The speed which had been reached 
by these balloons was indeed lamentably insuflBcient. Still it 
must be admitted that many preliminary points of importance 
had been considered and solved. Not the least of their achieve- 
ments was probably to be found in the fact that they had 
convinced the world that a dirigible balloon was likely to be a 
possibility of the immediate future, and one result of this was 
that there was no longer any insuperable difficulty in raising 
funds. France was certainly more lavish in this respect than 
most other countries, with the result that the French have 
succeeded in constructing a really serviceable airship. 



Count von Zeppelin, who bad distinguished himself over a well- 
known incident of the Franco-Prussian war, devoted his attention, 
after retiring from the army, to the construction of a dirigible 
balloon, a plan which he had long entertained. He formed a 
limited liability company for the purpose of raising the necessary 
moiiey, and started on the work in 1898. His balloon was the 
longest and biggest which had been made. It had a strong 
framework of aluminium, which was covered with linen and silk, 
treated with pegamoid. Special compartments were built inside 
for holding linen bags, which contained nearly 400,000 cubic feet 
of hydrogen. From end to end it measured 420 ft., and its 
diameter was 88 ft. There were two cars, in each of which was 
a motor, giving 16 horse-power. These motors were altogether 
independent of one another, and worked propellers which were 
rigidly connected to the body of the balloon. Vertical and hori- 
zontal screws were used for movements in the corresponding 
directions. A ** sliding weight" was used, if required, to raise or 
lower the front of the balloon and was moved by means of a 
winch along a steel support, on which h was carried. In this 
way it was possible to rise or fall over certain distances without 
loss of ballast or using the valves. Little was known about the 
probable results of the shock that would be experienced on coming 
to the ground in a rigid machine of this type. Schwarz's experi- 
ment was the only one which threw any light on the matter, and 
it was therefore considered safer to conduct the trials above the 
waters of the Bodensee. The construction of the outer envelope 
was a matter of great importance. It provided a smooth surface, 
and also protected the gas-bags from injury of any kind. More- 
over a thin film of air came between the gas-bags and the outer 
covering, and served to protect them from undesirable variations 



of temperature. This is a matter of great importance, because 
the indirect effect of radiation would otherwise be to cause a rise 
or fall. 

The first ascent was made in July, 1900, and it cannot be said 
that it was favoured by any unusual luck. The winch, which 
worked the sliding weight, was broken, and the whole balloon, 
together with the framework which connected the two cars, was 

Fig. 32. — Count Zeppelin's dirigible balloon. 

80 bent that the propellers could not be properly worked. Con- 
sequently full speed could not be reached, the maximum that 
was actually attained being 13 ft. per second, and it was also 
impossible to steer, as the ropes that were use^ for this purpose 
became entangled. These mishaps, which could not be rectified 
in mid-air, made it necessary to descend to the lake, where 
everything happened as had been expected, and the only injury 
that was sustained was caused by running on a pile. The 
damage was repaired at the end of September, and on 
October 21st a further attempt was made on the original lines. 


and ft speed of 30 ft. per second was reached. It was pointed 
out that a higher speed than this could probably be reached, but 
owing to the continual turns, it was impossible to get up full 
speed in any direction. Dr. Eergesell, the director of the 
Meteorological Institute in Alsace and Lorraine, undertook all 
the measurements. He determined trigonometrically the exact 
positions of three points, and from them continuous observations 
of the balloon were made. The speed of the wind was recorded 
on an instrument that was placed in a pilot balloon, and the 
figures so obtained may be confidently regai'ded as correct. 
The speed of the balloon was therefore greater than that of any 
o( its predecessors, and exceeded that 
of Renard and Erebs hy about 10 
ft. per second. 

At the end of another five years 
Count von Zeppelin had collected 
enough money to build a second 
airship. In the light of the experi- 
ence that had been gained in 1900, 
the new model of 1905 was improved 
in all its details. The most im- 
portant alteration was made bv 

., t ii, i Fia. 33.— Count Ze|i[(oUn, 

increasing the power of the motor 

without adding to its weight. Each car carried a motor, weigh- 
ing 8 cwt., and giving 85 horse-power. The body was about 
6 ft. shorter than before, while the diameter was slightly 
increased, the length being 85 ft., and tbe diameter 38 ft. It 
had 16 gas-bags, which lield 367,000 cubic feet of hydrogen, the 
capacity being about 32,000 cubic feet less than before. The 
total weight was 9 tons, which was a decrease of 1 ton. The 
four propellers were also somewhat larger. In front and behind 
were placed three vertical surfaces, constructed of linen, and 
intended to produce motion in horizontal directions ; between 
them and the cars horizontal surfaces were arranged, one above 
another, after the fashion of an aeroplane, in order to induce 
falling or rising movements. The steering was done by the 
occupant of the front car. 


The first ascent took place over the Bodensee on November 
80th, 1905. It had been intended to tow the raft, to which it 
was anchored, further from the shore against the wind. But the 
water was too low to allow the use of the raft. The balloon was 
therefore mounted on pontoons, pulled out into the lake, and 
taken in tow by a motor boat. It was caught by a strong wind 
which was blowing from the shore, and driven ahead at such a 
rate that it overtook the motor boat. The tow-rope was there- 
fore at once cut, but it unexpectedly formed into knots and 
became entangled with the airship, pulling the front end down 
into the water. The balloon was then caught by the wind and 
lifted into the air, when the propellers were set in motion. The 
front end was at this instant pointing in a downward direction, 
and consequently it shot into the water, where it was found 
necessary to open the valves. Certain slight damage was sus- 
tained, and a delay of six weeks took place. 

The next attempt was made on January 17th, 1906, when it 
was found that the lifting force was too great, and it rose at once 
to a height of 1,500 ft. When the propellers had been started at 
a lower level, it was found possible to move against the wind. 
But at a greater height a strong breeze was found to be blowing 
from the S.W., and the balloon was turned to face the wind. In 
consequence of lack of experience, it was found difScult to hit the 
mark, because the steering arrangements produced too strong a 
turning motion. In the meantime the balloon had reached the 
shore, and was carried with the wind, the motors having been 
stopped for various reasons. The descent was made without 
serious damage, although the anchor failed to hold in the frosty 
ground. A slight superficial rent was caused by rubbing against 
a tree. But during the night the wind did so much damage that 
Count Zeppelin was obliged to order it to be broken up. It is 
very diflBcult to form any decided opinion as to the merits of this 
design. At any rate it is certain that if the motors could produce 
a speed of 30 ft. per second, when working at 36 horse-power, 
the velocity would have been much greater if the full 170 horse- 
power could have been exerted. The latest news is to the effect 
that Count von Zeppelin has made a fm-ther attempt with a new 


balloon, and that this has been successful. Its stability is said 
to be very great, and it can be easily steered. According to 
Hergesell, a speed of nearly 50 ft. per second has been reached, 
which is far better than any previous record. 

About the same time, a young Brazilian, named Santos 
Dumont, appeared in Paris, and proceeded to astonish the world 
with his feats, which soon made him the most popular hero in 
the ballooning world. He had great wealth, as well as courage 
and perseverance, and constructed altogether fourteen balloons, 
making ascents in all of them with greater or less success. He 
knew nothing about the work of his predecessors when he set 
himself, without any experience, to the task of constructing his 
first balloon. 

List of Santos Dumont's Airships. 
















Cylindrical ; conical 






3 h.p. Dion • 

at back and front. 









Filled with coal 






Cylindrical : conical 
at back and front. 




7 h.p. Buchet. 


ditto. 1 19,400 



12 h.p. with four 



Elongated ellipsoid. 





Winner of the 


Deutsch Prize. 


ditto. 44,600 





60 h.p., weigh ing^ 
2\ cwt. 


(Sold to an American ; only made < 

)ne trip.) 


Egg-shaped. | 7,770 



3 h.p. Clement. 

" The Balladeuse." 


(26 Ibe.) 






20 h.p. 

" The Omnibus." 





16 h.p. with four 
(3i cwt.) 


(Placed at disposal of military auth 












15 h.p. Peugeot. 


(57 lbs.) 





Perhaps he can hardly be said to have hidden his light under 
a bushel, and technically considered, his results constitute no 
great advance on account of the small speeds he reached. But, 
on the other hand, he succeeded, as no one else has done, in 
arousing enthusiasm for the sport of ballooning, especially in 
England and France. Zeppelin's balloon represented the rigid 
type of construction, whereas Santos Dumont favoured a flabby 
envelope with a slight amount of stiffening, and used an air-bag 
to keep the thing in shape. The measurements are also alto- 
gether different from those adopted by Zeppelin, though he 
gradually adopted larger sizes. This resulted from the fact that 
he was obliged to use larger motors, 
1^ ' ^ as he found that the speed was 

V -^^^^^ insufficient. Heavier motors meant an 

I ^m % increase of weight, and this could only 

I W ^V be met by increasing the dimensions 

I '« J^ generally. 

It is extremely interesting to follow 
Santos Dumont on his ezpeditions. He 
succeeded in learning something on 
every occasion, and instantly proceeded 
to build a new balloon without giving 
a thought to the possibility of adapting 
the old one. He made very few ex- 
peditions in his first balloons, because he saw almost at once 
that they were unsuitable and that radical alterations were 
needed in the design. He went through all manner of accidents 
on his trial runs, but be also showed on many occasions 
that he well understood the art of guiding his ship through 
the air. He landed in trees, in the water, on the roofs of houses 
in rapid succession ; still his presence of mind always found 
a way of escape. His first attempt started very unluckily : 
the airship was at once dashed against the trees and torn to 
pieces. He said himself that the choice of an unsuitable starting- 
point was the cause of this accident. He made his ascent in a 
place that was surrounded by high trees. The force of the wind, 
which acted in the same direction as that produced by his 

—Santos Dumont. 


propellerB, drove him against the trees before he had time to rise 
above them. He then took the precaution of starting always 
with the front of the balloon towards the wind. The damage 
vas repaired in two days, and after performing some evolutions 
at a low level, he gained such confidence that he sailed from 
Paris to Longchamps at a height of 1,300 ft. At first all went 
well. As soon as the balloon fall, the gas contracted and the 
air-bag was seen to be too small. The balloon was no longer 
properly inflated, and it proceeded to fold up in the middle, like 
a pocket knife. It then plunged downwards towards the ground, 

FlQ. 3G. — SantM Dumont'B second baUooti breaks Ite back, 
May llth, 189». 

but Santos Dumont did not lose his presence of mind. He 
shouted to some small boys who were playing in a field, and told 
them to catch his guide-rope, and run with it as fast as possible 
against the wind. They did as they were told, and the air- 
resistance was so great that the balloon came gently to the ground 
without causing any injury to the driver. 

A new balloon was ready in the spring of 1899. The air-bag 
was now to be filled by a small rotating fan, whereas in the earlier 
model a pneumatic pump, similar to those in use on motor cars, 
had been employed. The whole thing snapped again in the 
middle, because the air-bag could not be iilled quickly enough to 
counteract the decrease of volume caused by the cold. It fell at 
once at a great rate, and the shock was luckily somewhat broken 

F 2 



by rebounding from the trees in the Jardin d'Acclimatation, He 
proceeded to build a new machine, which was of a different shape, 
and intended to be filled with coal gas, as this had the advantage 
over hydrogen of allowing an ascent to be made almost at any 
spot. He thought to prevent the long body of his balloon from 
collapsing by stiffening it with a bamboo rod, which was placed 
between the car and the body, and acted as a connecting link 
between the two. The first ascent was made on November ISth, 
1899, and was very successful. The start took place at the 
Champ de Mars, and the balloon made several circuits of the 
Eiffel Tower before 
descending. Itwas 
not easy to make 
a descent at the 
same spot in the 
middle of the town 
on account of the 
chimneys, and he 
therefore came 
down in an open 
field on the very 
place where the 
first accident had 
occurred. In order 
to have a more convenient spot for starting and landing, Santos 
Dumont built a shed in the grounds of the Aero Club, which was 
connected to the gas mains and was provided with an ap|:nratus 
for generating hydrogen. 

After he had made a few further trial runs with No. 3, he 
proceeded to build No. 4, which was shown in September, 1900, 
to the International CommiBsion, then sitting in Paris for the 
investigation of scientific ballooning. The car of the new design 
had the merit of simplicity. The driver sat on an ordinary 
riding saddle, and hie feet controlled the pedals connected to the 
motor. A tiller made connection with the rudder. The motor 
was joined rather lesa rigidly than before to the body of the 
balloon, and an important alteration consisted in placing the 

Dumoni's third balloon. 


propeller at the front instead of the back. With No. 4, he made 
several BatiBfactory ascents from the grounds of the Aero Cla)> 
at Saint-Cloud. He is stated to have asserted that the Com- 
mission were satisfied that this balloon could make headway 
against a strong wind, but on the day of inspection the breeze 
could only be called moderate, although it may be admitted that 
the standards by which the wind is judged are by no means well 
defined, and allow for differences of opinion, according to the 
point of view. Still 
he made no exact 
measurements of 
the force of the 
wind, and con- 
tented himself with 
estimates. Conse- 
quently his state- 
ments under this . 
head must be 
received with 
caution. On the 
other hand, it is 
only fair to allow 
that the instru- 
ments at present 
in use for the 
measurement of 
the wind are not altogether satisfactory. Perhaps the best of 
them is the one made by Gradenwitz. It depends on the gyro- 
static principle involved in the construction of instruments for 
determining the velocities of fluids. If a glass cylinder is filled 
with fluid, and rotated about a vertical axis, the upper surface of 
the fluid assumes the shape of a paraboloid of revolution, and the 
depression depends, as far as its magnitude is concerned, on the 
speed of rotation. If such an instrument is calibrated experi- 
mentally it is possible to determine the speed of rotation by noting 
the extent of the depression, always assuming that the volume of 
the fluid remains unchanged. Gradenwitz's instrumertt consists 

Flo. 37. — Gratleawili anemooieter. 


in the combination of a Robinson anemometer with a closed 
glass tube containing the fluid. The apparatus is set in 
motion by the wind, in the usual way, and it is then possible by 
noting the depression to tell the velocity at any instant. The 
calibration is carried out by means of the rotating apparatus 
used by the Meteorological Observatory at Hamburg. An 
instrument of this sort ought always to be used in trials of 
dirigible balloons. But even without taking into account any 
such measurements, the power given by the motor in Dumont*s 
last balloon was much too small. He therefore changed it for 
one having four cylinders ; it weighed much more, and it was 
therefore necessary to add to the size of the balloon by inserting 
a piece in the middle. At the same time he set to work on the 
making of a keel, which was 69 ft. long, and made of pine wood. 
It was triangular in cross-section, and covered with piano wire. 
Wire of this kind had been used by an American, named Rotch, 
for the purpose of holding a kite. A further novelty was intro- 
duced in the shape of a moveable guide-rope. The idea was that 
by moving the guide-rope either forwards or backwards, it would 
be possible to shift the centre of gravity of the balloon, and 
therefore to raise or lower the front end. He expected with the 
use of his propellers (which were placed at the back as in earlier 
models) to be able to rise or fall without the loss of gas or 

The first ascent with the remodelled machine took place on 
July 12th, 1901. After passing ten times round the racecourse 
at Longchamps, a distance of twenty-two miles, the balloon was 
directed towards the Eiffel Tower. On the way, one of the ropes 
connected to the rudder was injured, and this was repaired in 
the gardens of the Trocadero. He then sailed round the Eiffel 
Tower, and returned to the Aero Club after a journey of one hour 
six minutes. 

A prize had been offered by Monsieur Deutsch to the man who 
should succeed in sailing round the Eiffel Tower and returning 
to the starting-point at Saint-Cloud within half an hour, the 
amount of the prize being ±'4,000. Santos Dumont therefore 
notified the authorities that he was prepared to undertake the 


journey on the following day. But the motor did not work 
satisfactorily, and the balloon fell on a chestnut-tree in Roth- 
schild's garden. The attempt was repeated on August 8th, and 
again it met with a sudden end. A serious accident was indeed 
only just avoided. The balloon broke up, and the framework fell 
on the roof of a house near the Trocadero, and then plunged 
downwards into the courtyard. Firemen rescued the aeronaut 
from his dangerous position by lowering ropes from the roof, but 
the balloon itself was torn to shreds. Nothing daunted, his 
activity knew no bounds, and he set to work the same day on the 
plans for a new balloon. After much hard work it was ready in 
twenty-two days, and the ascent was made. In this model very 
special attention was paid to the valves, seeing that the last 
accident had been due to leaks. The rigidity of the design was 
increased. The air-bag was filled by a small fan, any excess 
being removed through a valve which opened automatically 
at a certain pressure. After some unsuccessful efforts, Santos 
Dumont succeeded with No. 6 in circling the Eiffel Tower and 
winning the Deutsch prize. He returned to the starting-point 
in 29 minutes 80 seconds, but the landing occupied another 
minute. Nevertheless the prize was awarded to him by 18 votes 
to 9, in spite of the fact that, strictly speaking, the precise condi- 
tions had not been fulfilled. He reached a speed of 22 ft. per 
second, which was very little better than the result obtained by 
Renard and Krebs in 1885. The prize was divided into two parts : 
i^'S,000 was given by the winner for distribution among the poor 
of Paris, and the remaining dt'1,000 was distributed among his 
assistants. The Brazilian Government sent him a gold medal, 
together with the sum of j£5,000, which was allocated towards 
the expense of new balloons. 

During the ensuing winter he continued his experiments at 
Monaco, where a large shed for housing his balloon was built for 
him by the Prince on the seashore. After some successful 
ascents over the Mediterranean in good weather, the balloon 
tilted over on February 14th, 1902, because the air-bags were 
not filled quickly enough to make up the loss in volume. It fell 
into the sea, and the aeronaut was safely brought to land. The 


balloon itself was not recovered till later on, and it was then 
found to have sustained such damage that it was sent to Paris 
for repairs. 

The later types were divided inside by partitions, which 
formed a series of chambers ; diffusion of the gas was therefore 
still possible, but any sudden rush of gas to the one end or the 
other was prevented. Mention shonld be made of No. 13, which 
was a kind of Rozih-e. The envelope was egg-shaped, and below 
there was a pear -shaped appendage, which had a large tubular 
opening, stretching down to the car. It was expected that by the 
use of a special form of petroleum burner it would be possible to 

I '-^isT" 


m^^ ..^r^ :<4 


l^^jdj .^^^^H^I^V™. "> ISS^^H 


Pr^- ff-i"».p'^" 


Fio. 3H.— Hoze's double balloon. 

rise or fall ; but it failed altogether to come up to expectation. 
According to the laws of diffusion, which have been already 
explained, the gas from the main body would penetrate into the 
auxiliary receiver, and in this way an explosive mixture would be 

The tests with the last types led to no fresh results ; the speed 
was always too small, and for military purposes they would have 
been useless. No. 9 was the most popular of the series. Santos 
Dumont went in this balloon to the racecourse at Longchamps, 
came down to the ground to watch the races, and then mounted 
again and went home. On another occasion he came down on 
the pavement in front of his own house, had breakfast, and then 
continued his journey. When the French troops were being 
reviewed by Monsieur Loubet, the President of the Republic, the 


balloon appeared opposite the grand stand and fired off a salute. 
He performed many other feats of a similar character, and 
though they may appear somewhat undignified, he succeeded in 
creating a widespread interest in the sport. 

It will be interesting to notice the results of his experiments 
with different kinds of motors. He started by using the ordinary 
motor, carried by tricycles, and mounted two of these, opposite 
to one another, so that they worked on one crank, and could be 
fed by one carburretor. He called this a " motor- tandem," and 
found that an arrangement of this kind worked well, when driven 
along the streets. He then wished to know the amount of vibra- 
tion which its working would be likely to cause, and the motor 
was therefore hung from the branch of a tree in the Bois de 
Boulogne. It was then seen that there was a slight amount 
of vibration when the motor turned slowly, but that this entirely 
disappeared when the speed was increased. With regard to the 
danger of an explosion, resulting from the mixture of the escaping 
gas with the air, Dumont stated that he had no fear on that 
score, seeing that the balloon would always be in motion, and 
consequently the escaping gas would never reach the motor. He 
said that he had seen flames 18 inches long dart from his motor, 
but that no accident had happened. He had more fear of a 
'' cold " explosion, i.e., of an explosion caused by expansion of 
the body of the balloon from any cause, supposing the valves to 
work badly. With petroleum motors, it is very necessary to be 
on one's guard against any accident, resulting in setting the 
petroleum reservoir on fire. On one occasion a fire of this 
nature occurred on board No. 9, but he luckily succeeded in 
putting it out with his Panama hat. His idea that escaping 
gases from the body of the balloon would not reach the motor, 
if in motion, is, however, incorrect. For instance, during the 
ascent it is quite possible that an accident might arise from this 
cause, and the necessary precautions must on no account be 
neglected. Another Brazilian, named Severo, met his death 
owing to an accident which was due to this very cause. His 
balloon, called the " Pax," was of a peculiar shape, and was sus- 
tained by an inner framework. Its capacity was 84,750 cubic feet. 


A noteworthy point in its construction was the placing of the 
two propellers at the ends of the longer axis. The front propeller 
was 13 ft. in diameter, and was intended to push the air aside, 
the back one, 20 ft. in diameter, was intended to drive the 
balloon forwards. In addition to these, there was behind the 
car a third propeller, 10 ft. in diameter. Two Buchet motors, of 
16 and 24 horse-power, were arranged symmetrically in the car, 
which was built up of bamboo rods together with tubes of steel 
and aluminium. 

Severo made an ascent on May 12th, 1902, in company with 
his friend Sach6, having previously made three ascents in a 
captive balloon. The working of the propellers had been tested 
while the balloon was held in a captive state by ropes. Shortly 
after the start, it was noticed that ballast was being thrown out, 
and that the propellers only worked intermittently. After a 
quarter of an hour, flames were noticed at the back of the car, 
and a violent explosion followed. Immediately after this, a bright 
flame was seen in the middle of the lower side of the main body, 
and another explosion took place. The balloon fell from a height 
of 1,300 ft., and Severo and his companion were killed on the 
spot. It was subsequently found that the petroleum reservoir 
showed signs of having been on fire, and the whole of the car was 
more or less burnt.^ 

The fault lay in placing the car too close to the body of the 
balloon ; the consequence was that there was always some of the 
explosive mixture in the car, seeing that during the ascent the 
hydrogen was escaping through a valve which was immediately 
above one of the motors. At the moment of starting, the speed 
was too small to allow this escaping gas to be swept away, and 
the explosion must have originated at the motor. The flame 
was then carried along the chimney, and came in contact with a 
stronger explosive mixture, with the result that a second 
explosion took place. The balloon then crumpled up, and as the 
outer envelope was not firmly secured, it did not act as a 
parachute, the fall being in consequence very rapid. Just before 

1 A full account of the accident is given by Es})itallier, an oflScer in the French 
ballo(jn corps, in the lUusirierte Aeiomnitmhe MHteilvrnjen 3, 1902. 

mmaiBLE balloons from isoe to 1906. 75 

etarting, Severo removed the pieces of wire(;auze, which had been 
provided for tlie sake of security, thinking himself that they were 
unnecessary. The Brazih'an Government, which had already 
shown ita interest in these experiments, has made provision for 
Hevero's family, and paid 1:1,000 to Sache's friends. 

The year 1902 was an unlucky one from the point of view of 
ballooning, and many fatal accidents took place. Captain 
Bartsch von Sigsfeld of the Prubsian balloon corps, who was 
well known from his work in connection with kites, was killed on 
the occasion of a descent at Antwerp on February 1st; soon 


\4 1 









Flu. 'M. — Keveiu'B balluon about to bUiI. 
afterwards, a French naval officer, who was carrying out some 
evolutions at Lagoubran, fell with bis balloon into the water and 
was drowned ; Hevero's death followed, and finally Baron von 
Bradsky was killed in Paris while making an ascent with a 
dirigible airs)iip. Baron von Bradsky-Laboun built an aerostat, 
which had an envelope just large enough to lilt the dead weight 
of the balloon ; any upward or downward movement was to be 
effected by menus of a propeller, working on a vertical axis, 
while motion in a forward direction was produced by ahorizontal 
screw, steering being, as usual, done by means of a vertical 
rudder. No air-bog was used. The balloon was 112 ft. long, 
and had a capacity of 80,0C0 cubic fett. The gas was prevented 
from flowing to either end by means of partitions, which divided 


the interior into three compartments. A frame was built up 
parallel to the longer axis ; sails were mounted on it, having an 
area of 865 square feet, and these could be lowered when 
required. The car was connected with the framew^ork by fifty 
lengths of piano wire, but very little lateral stiffening was used. 
Bradsky made an experimental ascent on October 13th, and a 
young engineer, named Morin, accompanied him ; both had 
previously made a couple of ascents as passengers in other 
balloons. Their plan was to sail towards the south-west against 
the wind, which only amounted to a light breeze. But they 
failed to do so, and were carried in a north-easterly direction. 
One of the propellers caused a tilt about the vertical axis, and 
they ascended to a much greater height than had been expected. 
Bradsky seemed to be about to give up the attempt, and began 
to descend. When he was about 800 ft. from the ground, he 
called out for information as to a suitable landing-place. As 
soon as he had satisfied himself about this point, it was noticed 
that Morin moved towards Bradsky, and the centre of gravity 
was shifted to such an extent that the car toppled over. Both 
aeronauts were thrown out and killed on the spot. General 
Neureuther's idea was that the accident was caused by the 
absence of sufficient rigidity, the result of which was that the 
piano wires became entangled and broke. 

However successful Santos Dumont may have been, it cannot 
be said that he produced a balloon suitable for military purposes. 
This work was accomplished by Lebaudy, whose balloon has 
been introduced into the French army with very successful results. 
The construction of this airship deserves careful consideration. 
In 1899 the brothers Lebaudy commissioned an able engineer, 
named Juillot, to make investigations into the design of dirigible 
balloons. The actual work of construction was put in hand two 
years later, and the first ascent was made on November 13th, 
1902. It was made of bright yellow calico, procured from 
Hanover, and was 187 ft. long, with a diameter of 32 ft., and a 
capacity of 80,000 cubic feet. It was fitted with a Daimler 
motor, giving 40 horse- j)ower; the total weight, including two- 
thirds of a ton of benzine, water and ballast was 2J tons. 


Twenty-nine ascents were made before July, 1908 ; on twenty- 
eight of these occasions, the balloon was able to return to its 
starting-place. The maximum speed was 86 ft. per second, 
though this statement has been disputed. The balloon had now 
been in use for seventy days, and its covering showed signs of 
wear : repairs were therefore carried out, and a fresh start was 
made in November. It was placed under the control of the 
aeronaut Juchmes, who was accompanied by a mechanic, and 
they brought it from tlie Champs de Mars to Meudon. As it 
descended, it was dashed against a tree and the outer covering 
destroyed. The motor was uninjured, and a new envelope was 
therefore put in hand at once. 

The " L6baudy 1904 " must be described more fully, as it is 
similar to that at present in use. Tiie unsymmetrical form of 
the first balloon was retained, but the pointed end at the back 
was somewhat rounded to an elliptical shape, and the axis was 
lengthened to 190 ft. Its capacity was 94,000 cubic feet, its 
surface 14,000 square feet, and the weight of the covering rather 
more than half a ton. The calico which had been brought from 
Hanover had turned out very satisfactorily, and it was therefore 
used on the new model. It was made airtight by coating with 
rubber both on the inside and outside. In France hydrogen is 
used which is prepared from sulphuric acid and iron ; in 
Germany chemically pure gas is ordinarily used, and prepared 
by the electrolytic decomposition of water. The former plan has 
the disadvantage of allowing minute quantities of sulphuric acid 
to be carried into the balloon, and therefore an inner coating of 
rubber is required in order to protect the calico from its effects. 
The air-bag was increased to a size of 17,650 cubic feet, and divided 
into three parts ; the fan was also arranged in a more convenient 
position, and placed closer to the main body. The air-chambers 
were so arranged in the first model as to be filled through a lone: 
neck which reached down to the car. This was found incon- 
venient, because at full speed the wind pressure was so great as 
to make it difficult to pass air into the neck. There was also the 
great danger which might arise if flames should break out in the 
neighbourhood of the motor, and be carried up by means of the 


neck. The fftn was therefore driven by the motor ; if the 
machine was at rest, an electric motor and a battery of accnmu- 
lators were carried to supply the necessary power. Besides the 
main valre, there were also two safety valves, which allowed the 
gas to escape under a pressure of 1'4 in. of mercury. Two small 

■windows were provided for inspecting the inside of the balloon. 
Every possible precaution was taken to ensure the stability of 
the machine. A horizontal oval-shaped sail of blue silk, having 
an area of 1,055 square feet, was stretched below the stand ; and 
beneath it there was a vertical sail, of much smaller dimensions, 
of the nature of a keel. At the back, which was elliptically 
shaped, surfaces having an area of about 240 square feet, and 


shaped like the tail of a pigeon, were arranged round the main 
body, and were crossed at the middle by a email vertical sail. 
Instead of having only one rudder, the new model had two, 
which were smaller and placed further back. They were movable 
about a horizontal axis, and of the shape of a Y, with the pointed 
end towards the front. When at rest, it was in a state of stable 
equilibrium ; if one of the sails gave way before the wind, the 
other merely offered an increased resistance. The driver could 
also alter their positions according to requirements. A slanting 
horizontal sail could be stretched across the front, and helped to 
balance the whole. A movable vertical sail, having an area of 
180 square feet, was 

provided for guiding 
the horizontal move- 
ments ; it could be 
turned about a vertical 
axis, slightly inclined 
towards the back. The 
car was boat-shaped 
with a flat bottom ; it 
was 16 ft. long, S ft. 
broad, and 3 ft. deep. 
The framework was of 
steel, and it was 


Flo. 41.— Car of L<!bftnd;'s balloOD. 

covered with thin sheets of aluminium. In order to increase 
the rigidity and at the same time to diminish the shock caused 
by reaching the ground, an arrangement of steel tubes, shaped 
like a pyramid, was placed below the car, with the apex down- 
wards. A guide-rope and an anchor were also carried. The car, 
which was only 10 ft. below the Iwdy, was more or less rigidly sup- 
ported by steel ropes about 0^2 in, in diameter. The 40 h.p. motor 
made 1,200 revolutions per minute, and consumed 31 lbs. of 
benzine per hour, the reservoir holding 48 gallons. At the front 
of the car an acetylene lamp was mounted ; by daylight this was 
replaced by a photographic camera, which was worked electri- 
cally. The total height of the balloon from the apox of the 
pyramid to the upper surface of the main body was 44 ft,' 


The first experimental run was made on August 4th. How- 
ever on the 28th of the month an accident happened. As the 
descent was being made, the balloon dashed into a tree, and was 
carried away by the wind, leaving its passengers behind. Four 
hours afterwards, it came to the earth, and it was found that 
little damage had been done. The *' Yellow," as the first balloon 
was called, made 12 ascents in 25 days. In all it made 63 
ascents. It had carried 26 different persons, among whom 
were the wives of the brothers Lebaudy, and altogether it took 
from first to last 195 passengers. The longest journey was made 
at Moisson on June 24th, 1908, when 60 miles were covered 
in 2 hours 46 minutes. The repairs necessitated by the above 
accident were completed on October 11th, 1904, and further tests 
were carried out, beginning on the 29fch. 

The '' Lebaudy " had in the meantime been much improved. It 
was fitted with a horizontal sail, 12 ft. long and 5 ft. broad, which 
could be rolled up ; this was carried in front of the car, and 
intended to produce movements up or down without loss of gas 
or ballast. Later it was found to be a very convenient device. 
The arrangements for lighting were also improved, and were 
used during the night of October 23rd. Each passenger carried 
a small lamp, which was fastened to his clothes, and two lamps, 
each of 100 candle-power, lighted the car and the lower side 
of the balloon. The candle-power of the acetylene projector 
was increased to 1,000,000. Eighteen journeys were made before 
December 24th, and the balloon was found to be completely 
under control. It was perfectly stable, and could always easily 
and safely be brought to the ground. The type of 1904 was, 
however, further improved. Among other things the cross- 
section of the main body was increased by 5 per cent. Calcula- 
tions showed that this was likely to increase the air resistance by 
about 11 per cent. But at any rate it has had no effect on the 
speed, because the motor was increased to 50 horse-power, as an 
indirect result of raising the capacity to 105,000 cubic feet. 
The weight of benzine and ballast was at the same time increased 
by 75 per cent. 

The French Minister of War paid much attention to the 


progress of the work, and thought it desirable to find out bow far 
Buch a balloon could be adapted to military purposes. He there- 
fore appointed a commission for thia purpose, which consisted of 
Colonel Bouttiaux, who commanded the Balloon Corps, together 
with Major Viard and Captain Voyer. A definite programme 
was proposed. Lebaudy was to sail to the camp at Chalons, and 
there carry out certain experiments ; after that, it was to be 

Fio. i2.—Liha}>dj'a dirigible balloon. 
taken to Toul and Verdun. The balloon was to remain in active 
service for three months, and always to be anchored in the open. 
Certain erections were made for the purpose of anchoring it, but 
they were not very successful in actual working. 

On July 3rd at 3.45 a.m., the balloon started from Moisson in 
the direction of Meaux, having Voyer, Jucbm^a, and Rey on 
board. Fifty-six miles were covered in 2 hours 35 minutes, and 
the balloon came to the ground at the precise spot where Lebaudy 
and his engineer were waiting. Tbe maximum height had been 
1570 ft., and 2 cwt. of ballast had been thrown overboard. 


Another ascent was made on July 4th, when Major Bouttiaux 
started from Meaux at 4.B8 a.m., and sailed against a strong east 
wind at the rate of 10 or 12 miles an hour. He landed at 
5.25 a.m., according to instructions, at a place called Sept-Sorts. 
The balloon was somewhat damaged on the following night in 
a thunderstorm; but he was able to make a further start on 
July 6th. At 7.59 a.m. he started from Meaux and passed over 
Chateau Thierry to Chalons, where he landed at 11.20 a.m., after 
a journey of 8 hours 21 minutes. The distance, as the crow 
flies, was 58 miles, but the balloon actually covered 61 miles. It 
was then anchored to some trees, where it was exposed to a strong 
wind. It was soon torn away from its moorings, carried over 
some telegraph wires to a height of 1,000 ft., and subsequently 
dashed against trees with considerable violence. The envelope 
was completely destroyed, but three soldiers, who had been left 
in the car to attend to it, escaped without serious injury. The 
Minister of War provided immediate facilities for the work of 
repair. It was astonishing to find how easily the repairs were 
executed without having recourse to the factory at Moisson, and 
without the provision of any special appliances. This was due 
in large measure to the energy displayed by Julliot, who showed 
great ability in controlling the execution of the work. A riiing- 
school belonging to the d9th Artillery Regiment was used as a 
workshop. Another riding-school was also placed at their dis- 
posal, and the ground was excavated so that the balloon, together 
with the car, could be placed on the floor. In addition to this, 
a small installation was prepared to generate the hydrogen, 
together with scrubbers, driers, etc. The work occupied 150 
men for 11 weeks, and on September 21st gas was again passed 
into the balloon. On October 8th, the Minister of War happened 
to be in Toul on a visit of inspection, and though the weather 
was windy and rainy, Julliot determined to make a start. A 
series of evolutions took place over the military hospital, and the 
return journey was then made. A further expedition was made 
on October 12th, starting at 7.36 a.m., with 930 lbs. of ballast. 
They passed over the fort of Gondreville, and all the fonitica- 
tions in the neighbourhood of Nancy, returning to Toul, where 


they landed at 9.50 a.m. In 2 hours 14 minutes they had covered 
82 miles, the maximum height being 2,230 ft. On October 18th, 
the seventy-second ascent was made with five passengers on 
board. The instructions were to the effect that photographs 
were to be taken of the various fortifications, and a sack of 
ballast was to be thrown down at a given spot. Everything passed 
off according to the plan, and in spite of throwing out the 
ballast, the maximum height was only 1,800 ft. A fan was 
carried, which could pass 35 cubic feet of air into the air-bags in 
a second. The loss caused by throwing out 44 lbs. of ballast was 
quickly made good by pumping 635 cubic feet of air, and the 
further rise of the balloon was prevented. 

A series of ascents were then made by some of the commanding 
officers, and took place without any accident, though the weather 
was not precisely calm. On the 24th of October the seventy- 
sixth journey took place, when the Minister of War, together 
with his adjutant, Major Bouttiaux, Captain Yoyer, and others, 
made the ascent. On November 10th, the balloon was allowed 
to retire into winter quarters after having had a truly brilliant 
career. Reports state that other balloons of a similar design 
have been put in hand at Moisson and Toul, and that they are 
to be kept at the forts along the frontier. The cost of a balloon 
of this type is from £10,000 to j£12,000, and cannot be considered 
unreasonable in view of the services which it could render in 
case of war. The cost of the experiments is not exactly known, 
but it is believed to have been between £100,000 and £150,000. 

The successes of Santos Dumont and Lebaudy have spurred 
others on with the desire to rival their feats. Count Americo da 
Schio has a peculiar method of working without an air-bag, and 
alleges that he can rise without losing gas and descend without 
alteration of the shape of the envelope. His balloon has a cigar- 
shaped body, 130 ft. long, 20 ft. in diameter, with a capacity of 
42,500 cubic feet. A broad band of rubber is placed inside, and 
as the gas pressure increases, it stretches from 4f ft. to 11 ft. 
A safety valve comes into operation before such pressure is 
reached as would be sufficient to burst the rubber band. Some 
trial trips were made at the end of 1905, and the arrangements 

G 2 


worked well, according to report. This sounds surprising in view 
of the facts stated by Monsieur de Quervain, one of the Directors 
of the Meteorological Institute at Zurich. He points out that a 
rubber band offers the greatest resistance at the moment when 
the extension begins, and that this resistance decreases during 
the process of extension, gradually increasing shortly before it 
breaks. From this it would seem that the automatic valve would 
operate at the beginning of the extension ; in fact, the rubber 
would never be extended at all. This will be noticed on blowing 
air into an india-rubber ball, when it will be seen that the 
greatest lung power is required at the moment of starting. A 
further peculiarity of this balloon consisted in coating it with fine 
aluminium powder, which was intended to prevent it from being 
heated by the sun to the same extent. 

Much interest has lately been aroused in Germany by the 
work done by Major von Parseval. He has invented a kind of 
kite-balloon, and has built a motor-airship in the factory of 
August Riedinger in Augsburg. The work is not yet complete, 
but it has been possible to produce a speed of twenty-five miles an 
hour even under somewhat disadvantageous conditions. One 
advantage of this airship lies in the fact that there is an 
absence of rigid connections, except in the car, sails, and 
rudder. Consequently it can be packed up easily and put 
on a railway truck. This adds much to its suitability 
for military purposes. Lebaudy*s airship is indeed capable of 
being packed up, but it requires to be taken to pieces in conse- 
quence of stiffening of various kinds, and this work takes more 
than a day. The shape of Major Parseval's design is also novel. 
It consists of a cylinder with a spherical end at the front and an 
egg-shaped end at the back. The length is 157 ft., and the 
capacity 88,300 cubic feet. Two air-bags are placed inside the 
envelope, one at the front and one at the back. These bags are 
constantly filled by a fan, driven by a special motor, any excess 
of air escaping through the safety valves. By a special arrange- 
ment of valves, the driver is able to adjust the amount of air 
which passes to the air-bags. According as he wishes to raise 
or lower the front end of the balloon, he adjusts the passage of 


the air to the back or front air-bag, thereby causing a displace- 
ment of the centre of gravity. The BUrfaces, which are UBed for 
steering and for adding stability to the balloon, are blown up 
under presBure, and the shape which they thus assume is 


coQBidered to be more suitable for the purpose in view. A motor by 
Daimler ia used, giving 90 h.p., at 1,000 revolutione per minute. 
It IB placed at the back of the car, which ia 16 ft. long. The car 
ia hung by ateel ropes about 26 ft. below the enveloije, and is 
constructed for the most part of sheets of aluminium. Its 
weight, together with that of the motor, propeller, etc., is IJ 
tons. The propeller with its four blades is prepared from stiff 
canvas ; it assumes its proper ahape wlien put in motion. The 
fan is placed above the motor, and a length of tubing connects 
with the envelope. Tests have shown that 
the balloon keeps its shape well, that it is 

t^— completely free from vibration when under 

^fjT weigh, and that it is well under control both 

with regard to movements in a horizontal 
and vertical direction. By altering the in- 
clination of the axis of the balloon it is 
possible to rise or fall without loss of gas or 
ballast. The reaction produced on the upper 
or lower surface of the balloon, frhen moving 
at full speed, is sufficient to give rise to forces 
ot several bundled pounds. It is very im- 
portant that a balloon, intended for use in 
the field of war, should be capable of being 

easily piicked. Count do la Vaulx has there- 

Fic. 44.— Count dt! f^j-g \jxii\t a motor balloon which is capable 
la Vaiili ^ 

of being taken apart with great ease, and 

packed in four parts. The first package contains the envelope, 
find occupies about 35 cubic feet of space; the second contains 
the ear, re<juiring Hoor space to the extent of 2 yards by 1 
yard ; and the third and fourth contain the portions of the keel. 
Count de la Vaulx also uses yellow cambric of German make, 
because it is as yet impossible to obtain it of sufficiently good 
quality in France. The two thicknesses of cambric are usually 
separated by a layer of rubber, Imt there ia a further coating on 
the outside. This is done with the object of preventing the 
absorption of any moisture. It is known that the covering of a 
balloon, having a capacity of 4G,000 cubic feet, can absorb about 

























fe OT 

5* « 



g hi 
a ^ 

^^ > 

s a 

«^ "■ 







2 cwt. of moisture, and it is evident that a dead weight of this 
order may have considerable effect on the length of journey 
which it is possible to undertake. A balloon of a capacity of 
25,000 cubic feet has great advantages from the point of view of 
transport, and also takes a small amount of gas. Both of these 
matters are of importance from the military point of view. On 
the other hand, it has the disadvantage of being able to carry only 
one passenger. It is obvious that a man requires all his wits 
to manage a dirigible balloon, and would be unable to find any 
time in which to make observations in the capacity of a scout. 
Count de la Yaulx therefore proposes to increase the size of his 
airship, and the trial runs have turned out to his satisfaction. 

Many other dirigible balloons have lately appeared, which 
have all met with their share of success and failure. A short 
table is added, giving particulars of the airships most frequently 
mentioned in the daily papers, together with some particulars as 
to their construction and performances. It must be admitted 
that the construction of a dirigible balloon is a difficult matter, 
but a combination of patience, skill, and money will generally 
lead a man to the goal. The problem is therefore not so much 
how to build the balloon as how to raise the money. Any 
government or any private person in possession of the necessary 
means can easily construct such things if they have recourse to 
men of technical experience. 


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Flying machines include all such devices as enable a man to 
fly without the use of gas-bagB, and to move in any direction 
with the help of such contrivances as are carried on board. Two 
forces are therefore needed ; the one to overcome the force of 
gravity, and the other to deal with the resistance of the wind. 
The oldest of these aerodynamic airships were worked by means 
of contrivances of the nature of wings. The flight of birds was 
the obvious example to be imitated. It would be merely neces- 
sary to provide suitable means for flapping some kind of artiti- 
cial wing, and the thing would be done. Some devices of this 

Fia. 4f>. — Degen's flying machine. 

nature lia^e already been described. In 1784 Gerard constructed 
a flying bird ; the wings were moved by mechanical devices, 
hidden in a box, but the details of bis arrangement are not 
known. A man, named Meerwein, wrote a book in which he 
carefully investigated the subject of the flight of birds, and at 
the same time described a flying machine he bad constructed. 
He is said to have made some unsuccessful experiments near 
Giessen, but he threw out the useful suggestion that experiments 
of this kind were best conducted over an expanse of water. 

Blanchard made several ascents in Vienna, and this encouraged 
a watchmaker of Basle, named Degen, to construct a flying 
machine. With the help of some counterweights, he was able to 


fly short distances in a large hall. He made some unsuccessful 
experiments in Paris, and was so roughly handled by the mob 
that he afterwards preferred to do his work from the shelter of a 
balloon. All sorts of proposals of the most complicated kind were 
made in the course of time, but no success resulted. A man, 
named Buttenstedt, who was an ardent champion of winged 
machines, had curious ideas which he proposed to put into 
practice. He studied the position of the wings during the flight 
of storks, and developed a wonderful theory relating to " elastic 
tension." He pointed out that when the bird is at rest, the tips 
of the wings are pointed downwards and backwards ; when it is 
flying, they are pointed upwards and forwards. They reach the 


Fia. 47. — Diagrams illustrating Maiey's theory with reference to the 

flight of a bird. 

forced position, natural to flight, as a result of the reaction due 
to the upward pressure of the atmosphere on their bodies. This 
state of " tension " puts the bird in a position to exercise a certain 
pressure, which drives it forwards. The onward movement 
ceases when the pressure, exerted by reason of this tension, is no 
longer sufficient to overcome the resistance of the air. According 
to this view, the essential feature in the flight of a bird lies in the 
state of tension, succeeded by a corresponding state of relaxation. 
A bird can only fly forward, because the positions of its wings 
and of its centre of gravity do not admit of a backward movement. 
A Frenchman, named Marey, also made a special study of the 
subject, and found that a bird does not drive the air backwards as it 
flaps its wings in a downward direction, but flies in such a manner 
as to bring the tips of the wings towards the front. The tips of 


the wingB do not move as shown at A, but ae shown at B. As 
the bird flies forward, it does not drive the air from under its 
body, but throws it, from the side and from behind, beneath the 
body ; at the Bame time the force of the downward blow alters 
the shape of the feathers from a downward concavity into an 
upward convexity. These forces tend to drive the bird forward 

stent Eel's flying uachine. 

in exactly the same way as a fish is propelled by the movement 
of its tail. 

There was at any rate a better prospect of success as soon as it 
was proposed to use some form of engine as the motive power. 
Two attempts on these lines deserve mention. An engineer, 
named Stentzel, of Hamburg, constructed a gigantic bird ; the 
distance between the tips of the wings was 20 ft. ; the wings 
themselves were 5 ft. 6 in. broad, and formed a concavity of 1 in 
12. They were covered with silk, the main ribs being of steel 


and joined by small connecting rods to a carbonic acid motor. 
It was intended to steer by means of a nidder, shaped like a 
cross. The surface exposed to the air was 87 square feet, and with 
an output of 1*5 horse-power, a weight of 75 lbs. was lifted from 
the ground. It was possible to make 84 flaps of the wings in a 
minute, and they were so powerful that a man was almost swept 
off his feet by them. Unfortunately this type was not found 
suitable for an extended trial. Flying machines with wings 
seem unlikely to promise great results, partly because questions 
of stability arise with which it is difficult to deal, and partly 
l)ecause a slavish imitation of bird-mechanism is hardly likely to 
be more successful than a human automaton. 

The idea of using propellers was an improvement. This 
appears in its most primitive form in the scheme of Launay and 
Bienvenu, who used the tension produced by a stretched bow to 
produce rotation of the screw. Ninety years later, P^naud 
improved on this design by proposing the use of rubber bands 
for a similar purpose. But here again it soon becomes evident 
that without some continuous motive power, little can be 
accomplished. For many years, nothing was done, but lately 
the problem has been further discussed in view of the great 
improvements which have been made in the art of building 
motors. The first idea was to revive the ancient models. A 
small machine was made by an engineer, named Kress, with 
rubber bands, on the lines proposed by P^naud. On the occasion 
of a lecture, he succeeded in making it fly up to the ceiling. 
There is also a well-known toy which consists of a small screw, 
set in rapid rotation by pulling a string ; the result being that 
the thing flies up in the air. A toy of this kind was common in 
France fifty years ago under the name of Straiyheor or 
Spiralipre. It is still to be seen nowadays in the form 
of butterflies, etc. 

A man, named Leger, has lately made some experiments with 
the help of the Prince of Monaco. He used two screws of 20 ft. 
diameter, which were driven by a motor, giving 6 horse-power, 
and produced a tractive force of 240 lbs. The same propellers 
can be used to produce vertical and horizontal movements. If 



the propeller works on a vertical axiB, the apparatus will rise ; 
whereas if the axis is inclined to the horizontal at an angle 
of 45 degrees, a forward motion can be obtained. Dufaox 
worked at Geneva with a model which had propellers, weighing 
37 lbs. It was fitted with a 8 horse-power motor, and produced 
a pull of 14 lbs. On October 28th, 1906, it is said to have flown 
over a distance of 500 ft.^ 

We seldom find a man imbued with the ideas of the balloon, 
adapting himself to the principles of the flying machine with any 
success. Yet it was done by the most popular balloonist of our 
time, Santos Dumont. On January 2nd, 1905, he announced 
himself to the Aero Clnbas 
a competitor for tbe Deutseli 
and Archdeacon prize, after 
he had quietly built him- 
self a flying machine. As 
shown in the appended 
diagram, the two upper 
propellers C C have a dia- 
meter of 20 ft., and produce 
motion in a vertical direc- 
tion ; the propeller D. has 
a diameter of 6^ ft., and 
drives the machine for- 
wards. Each of the propellers C has a total surface of 43 square 
feet, and together with the transmission gear it weighs 30 lbs. The 
one revolves in the opposite direction to the other, so as to prevent 
a rotation of the entire apparatus about a vertical axis. The car 
is constructed of bamboo, and contains a Levavasseur motor with 
eight cylinders, giving 28 horse-power. The weight of this motor 
together with the necessary supply oE water is 1 cwt. At the back 
of the driver's stand is placed a vertical rudder. The preliminary 
trials are said to have been successful and each of tbe lifting pro- 
pellers was found to be able to raise a weight of 200 lbs. ; tbe total 
lift was therefore 400 lbs., and this could raise tbe machine and 

' St-c altui " rroceclinga of the Inlcrnalional t'onference on Aerinl Navigation at 
<'1iicHgu," 11)03, p. 2H1 ; and l.ecciriiu, " l^a Navigation A(^ricnne," p. 3!)7. 

B machine with 



driver, besides about 80 lbs. of cargo. He used no sails, and 
this would add greatly to the danger of an accident caused by 
stoppage of the motor. In such a case he would S3arcely get off 
so easily as he has done in the past. No doubt this fact weighed 
on his mind, for he proceeded forthwith to build himself a kite, 
intending to drive it by propellers placed at the sides of the 
sails. The rudder is in the shape of a cross, and capable of 
being turned about both horizontal and vertical axes. The sails 
are of silk, stretched over bamboo, and are 50 ft. long and 26 ft. 
broad, with an area of 237 square feet ; the weight of the whole 
machine together with the driver is only 810 lbs. He has 
already made two ascents in this airship. On the first attempt, 
it rose in the air, 
but after a short 
distance it came to 
the ground with 
rather severe in- 
juries. Santos Du- 
mont immediately 
built another, and 
in this he is stated 
to have travelled a 
distance of 200 ft. 



Fig. 50. —Santos Dumont*8 first flying machine. 

at a height of 12 ft. from the ground. This aeroplane is of 
a totally different nature from the original design of flying 
machine adopted by Santos Dumont ; and it cannot be doubted 
that it is the thing of the future. It would be exceedingly 
dangerous to propose to do without sails of any kind ; a motor is 
capricious enough, even when standing on solid earth ; in mid 
air, it is likely to be more so. The weight of kites or aeroplanes 
is small, and they have the further advantage of presenting a 
small surface to the wind, in consequence of their horizontal 

A kite may be defined as a flying machine, carrying sails, 
which support the weight of the apparatus. The sails may be 
large or small, flat or concave, and are for the most part slightly 
inclined to the horizontal. The forward motion may be produced 


indirectly by gravity, as, for instance, in the case in which it is 
allowed to fall slowly from a height with its sails slightly inclined 
to the horizontal. Or on the other hand it may be moved forward 
by the action of propellers. Motion in a vertical direction may 
be induced by a propeller arrangement of the sails or by moving 
a horizontal rudder. Steering in the ordinary sense depends on 
the position of vertical sails, and the possible arrangement of sails 
is almost infinite, as will be seen from the following examples. 

The first aeroplane, driven by motive power, was the work of 
an Englishman, named Henson, in 1843. A light framework of 
wood was constructed, 100 ft. broad, and 30 ft. long. It was 
covered with silk, and slightly bent upwards at the front. A 
rudder, shaped like the tail of a bird, and 50 ft. long was used ta 
steer in a vertical direction. The car was placed below the main 
sail, and contained the steam engine and passengers. Two screw 
propellers were placed on either side of the driver ; the speed of 
these could be regulated, and by suitable adjustment it was 
possible to turn to the right or left. The steam engine gave 
20 horse-power. The machine was built on correct principles and 
caused great excitement ; but Henson only succeeded in making 
it work over a downward path. The air is always compressed 
beneath the sails of an aeroplane, and this exerts a lifting or 
supporting force. Generally speaking, it is impossible to main- 
tain a position of equilibrium, because motion is necessary for the 
continued compression of the air. Henson's propellers were 
probably insufficient to generate the requisite lifting power ; but 
it was generally admitted that patience would bring success. 
Consequently a multitude of proposals were made, for the most 
part of no great importance. Perhaps mention ought to be made 
of a lieutenant, named de Temple, who prepared very careful 
plans for the construction of a kite, to be driven, as before, by 
propellers and steam engine. 

Phillips made a curious form of flying machine in 1862. It 
somewhat resembled a Venetian blind, supported on a wooden 
frame. The height was 9 ft. 3 in., and the breadth 21 ft. 8 in. 
The whole thing was mounted on a carriage, shaped like a boat, 
and running on wheels, 24 ft. 6 in. long. It was driven round a 



circular track, 600 ft. long, by a Binall steam engine comiedted' 
to propellers, making 400 revolutions per minute. The weight 
of the whole was rather lesB than S cwt. It was anchored by a 
rope to the middle of the track. The tests showed that a dead 
weight of 72 lbs., placed on the front wheels, could be lifted 
80 ins. into the air, and this proved that the principles of con- 
struction were correct. It seems curious that after such 
preliminary success nothing further should have been done. 
But the difficulty is to determine the right position for the 
centre of gravity, and to ensure a reasonable amount of stability 

Flu. 51.— Phi 

when in motion. These points can only be settled after the 
expenditure of much time and money. 

Some of the most interesting experiments were carried out by 
Sir Hiram Masim in 1888, with the assistance of the late Pro- 
fessor Langley. The aeroplane cost over i;20,000, and was 
designed on a large scale. It consisted of a big sail with a 
number of smaller sails to the right and left of it, having 
altogether an area of 3,875 square feet. They were connected to a 
platform, 40 ft. by 8 ft., by means of a framewofk, built up out 
of thin steel tubes. The platform contained a seat for the 
driver, together with the boiler, engine, etc., and the boiler was 
fired by a gas-burner, which was fed with naphtha. The burner 


itself conBisted of a cylinder with a number of Iiorizontal tubes 
and about 7,650 jete. The diameter of the propellers was 
17 ft. 6 in. The 
vertical movements 
of the machine were 
controlled by two 
horizontal sails, one 
at the front and one 
at the back. Hori- 
zontal movements 
were regulated by 
two sails, inclined to 
one another at an 
angle of 7'5 degrees, 
and arranged on 
either side so as to 
be capable of being 
hoisted or lowered, 
the result being to 
shift the position of 
the centre of gravity 
and consequently to 
alter the direction 
of motion. The 
machine weighed 3^ 
tons, and for the 
purposes of the trial 
runs it was mounted 
on four wheels and 
put on a railway 
track. An overhead 
rail was placed a few 
inches above the top 
of the machine with 
a view to controlling 
the upward motion. With a steam pressure of 22 atmospheres, 
the machine rose off the lower rails and came in contact with 


the upper one. Daring a later test, the overhead rail was 
broken by the force of the impact. The machine flew away 
across the field, and was partially destroyed. A dynamometer . 
showed that a dead weight of 4} tons would have been lifted, and 
as a result of these tests it is safe to affinn that it is possible to 
design aeroplanes of great weight. 

During the Exhibition in Paris in 1900, a peculiar form of 
flying machine was to be seen, which looked like an enormous 
bat, A Frenchman, named Ader, bad built it, with the assist- 
ance of the Minister of War. The sails were of the nature of 
wings, and could be folded up at the back. In addition there 
were two propellers, each with four blades, driven by power. 
The nhole apparatus weighed nearly half a ton, but it managed 

FlO. 53. — Ader's flying mschine. 

to lift itself off the ground. It soon toppled over, and was much 
injured in consequence. An engineer, named William Kress, 
living at Vienna, also distinguished himself by making a flying 
machine. He had been interested for many years in the sport- 
ing features of the problem, and finally began to study the matter 
in its scientific aspects. The model which he made with rubber 
bands has already been noticed. His designs received their 
final shape in June, 1901, when he started his trial runs on a 
reservoir near Vienna. The machine was mounted on two 
narrow boats, made of aluminium. The boats served a double 
purpose. Tbey were useful in case of unexpected descents into 
the water, and on the other hand they could be used to slide it 
over snow or ice, as he bad an idea that a flying machine of this 
kind might be useful on polar expeditions. A frame of steel 
tubes was mounted over the boats, and on this the sails were 
fastened. The design took the form of a keel with the sharp 

l.«V " 2 



end pointing forwards, and with its lower surface acting as a 
sail. Above this were mounted three other sails, one behind the 
other, inclined at different angles, the total area of the sails bein^ 
1,000 square feet. They were slightly concave, to the extent of 
1 in 12, with the view of offering more resistance to the wind. 
The original intention was to use a motor weighing 13 cwt., but 

the boat was built 
before the motor 
was ordered. Some 
preliminary experi- 
ments were made 
with a 4 horse-power 
motor, treating the 
machine as a sailing 
boat. He was able 
to sail about in any 
direction on the 
reservoir, and even 
to make headway 
against a slight 
wind. A Daimler 
motor of 85 horse- 
power was then or- 
dered, and it was 
stipulated that it 
should only weigh 
530 lbs., but when 
delivered it was 
found to scale 840 lbs. 

Fig. 54. — Kress's flying machine. 

However, this motor was used in spite of the fact that it was 
nearly 4 cwt. heavier than the weight allowed for in the design. 
The money had been spent, and it was not possible to make 
great alterations at this stage. Kress brought the boat on rails 
down to the water's edge, and then very carefully performed 
certain evolutions. Gradually his courage increased, he ran the 
motor a little faster, and found that at 18 horse-power there was 
a tendency for the boat to be lifted out of the water. He 


reached the end of the lake in 20 minuteH, and then proceeded 
to turn back. At this moment the boat swayed first to the left 
and then to the rif;ht, and as a result ol these vibrations it got 


into such a position that it was unable to right itself. A go^ of 
-wind added to the difficulty, and there was nothing to be done 
but to jump into the water. A man had been deputed to be 
ready with a boat in case of accident. But he was so overcome 
by the dangers that stared him in the face as to be obliged to 
get further assistance before making a start. Kress was finally 
rescued as he was on the point of being drowned. The remains 
of the kite were found after some days; the motor was 
uninjured, but everything else was a confused mass of wires and 

Experiments on the water, conducted after this fashion, give a 
totally wrong impression of the probable behaviour of a kite in 
the air. On water, the point of support is below the centre of 
gravity ; in the air, it is just the other way round. Therefore 
those contrivances which are likely to increase the stability in 
the air will only tend to upset it on the water. Attempts have 
been made to raise money in Austria in order to help Kress to 
make further progress with his work ; but up to the present little 
appears to have resulted from these efforts. 

Professor Langley has also carried out his experiments in 
America over the surface of water. He was director of the 
Smithsonian Institute at Washington, and died in March, 1906. 
He tested his first model over the Potomac Biver in 1896. His 
*' aerodromes " Nos. 5 and 6 gave satisfactory results. He had a 
special arrangement for starting, which consisted in sliding it ofiT 
a swinging table into the air. A barge was used as the starting- 
point. Mr. Frank Carpenter stated that the best result was 
obtained on December 12th, 1896, when a distance of a mile was 
covered in 1 minute 45 seconds. Langley conducted his work in 
the greatest secrecy, and Mr. Carpenter was indeed present at 
this test quite by accident. Dr. Bell reported in Nature 
(May 28th, 1896) that to his knowledge two successful trials had 
taken place. A drawing in the Aeronautical Annual for 1897 
shows that Langley's " Aerodrome No. 5 " had the following 
measurements, viz., length without rudder 8 ft. 6 in., total span 
15 ft. The bearing surfaces consisted of four sails, the length of 
each sail being 30 in. Two propellers were driven by steam in 



opposita directiona, the steam pressure being 150 lbs. per sqnare 
inch, and the diameter of the propellers S ft. The weight of 
the entire machine was about 28 lbs. The only information to 
be had aboat " Aerodrome No. 6 " was to the effect that it came 
to grief on its trial nm, and the same thing happened to its 
BoccesBor. The last kite bad two immovable sails on each 
side, which were rigidly connected by a steel framework to 

Fia. 66. — BtwtiDg BiraiigementB for ProCcwoi' Luigle;'* fljiog machine. 

the boat, the breadth of the machine being aboat 46 ft., and 
the depth S3 ft. It was driven by two propellers arranged at 
the sides. 

Professor Manley, who helped Langley, is said to have made a 
trip along the Potomac Biver in the following fashion. The 
workshop bad a horizontal platform 30 ft. above the level of the 
water. The aerodrome was mounted on s car, which was pushed 
rapidly forward by means of strong springs. The movement of 
the car was stopped as soon as it reached the edge of the plat- 
form ; the aerodrome then slid off, and aft«r dipping down for a 



short distance, it turned upwards and continued its flight. This 
at any rate was the intention ; but according to the reports of 
the Smithsonian Institute, there was a slight hitch in the pro* 
ceedings, which resulted in the sudden immersion of the airship. 
It was prevented from sinking by certain hollow cylinders, which 
had been thoughtfully fixed to it at different places, and Manley 
was eventually rescued from the water. 

The arrangements for starting are of great importance. It has 
he&a already pointed out that a certain amount of kinetic energy 

Fio. 67.— 

miiHt be created in order 
that the air may be 
Bufficiei! tly c o »i p r o s fi ed 

ben,;rlll lllr ^ilils. TIil' 

machine can then hover 
in the air. The motors 
have then their work to 

do in the shape of driving it forward. As a start, it would be 
satisfactory to make the machine work with special arrangements 
for launching it ; but it ought to be understood that this is only a 
temporary expedient. Otherwise the area over whicii it would be 
possible to fly such a machine would be very limited. This point has 
been borne in mind by another inventor, Herr Hofman of Berlin, 
who uses the kinetic energy generated by the tall to start his 
machine. It is built on legs or stilts. When ready to start, the 
legs are laid against the body, and the wings folded together in the 



middle. Just before the flight begins, Ibe wings are unfolded and 
the legs placed more upright. The centre of gravity is therefore 
raised, and the machine ia started in this position, so that the pro- 
pellers can be set to work. A considerable speed is soon reached, 

Fia. GS. — Hofmann'i first model irith carbonic acid 

because the sails are carried in a horizontal position. The legs 
are then jerked up against the body, and the whole thing begins 
to fall. In doing so, it turns over so that the sails are no longer 
parallel to the ground, while the motor continues to drive it 

Hofnituiii's working model. 

forwards. But this upward movement is only intended to last 
an instant. The wings soon get into such a position that they 
are able to take the whole load, and as the machine moves 
forward, fresh quantities of air are successively compressed 



beneath the wings. The upward reaction becomes bo great that 
the machine not merely floats but. soars higher, continaing its 
fli>;ht steadily under the influence of the propellers. If k fall 
should take place, the speed of falling, is much rednced by the 
reaction of the exposed surfaces, exactly in the same way as with 
parachutes. The correctness of the inventor's ideas is probably 
shown by the fact 
that he has often 
publicly exhibited a 
Bmall model, reduced 
in the proportion of 
1 to 10, which flies 
successfully in a 
large hall. 

The machines 
which have been 
described were in- 
tended to be worked 
by motors, nnd even 
in the smallest de- 
signs, such was 
always the case.* 
Many, however, be- 
lieve that this is 
wrong in principle, 
in BO far as experi- 
ment is concerned. 
Their idea is that 
the first step should be in the direction of floating, and that 
when sufficient is known to deal with the niceties of that art, it 
will he reasonable to talk about working with motors. 

The man who first started on these lines was a German, named 
Lilienlhal. His methods have been much imitated in France 
and America, and require to be fully described in order to under- 
stand the problem of floating motion. When he was a schoolboy, 
he tried the most primilive methods. He fastened wings to his 
body, and tried to get sufticient ini{>etus for ihe start by running 

Kla. 6(1.— Uerr HofmBon and Mr. Patrick 
AleuLDdet Id the workshop. 


down a hill. Later on, with the help of hia brother, he used 
sails, which were distended to repreeent the wiogB of a bird, and 
made of calico, supported on a frame of wickerwork. He sat 
with the lower part of his arms resting on the frame ; in this 
way he controlled the novemeDts of his machine. In a strong 
wind, he would soar above the beads of the astonished spectators; 
under other conditions, he would appear to float, almost at rest. 
This simple type of sail led Lilientbal to develop other designs, 
with a view to having greater control over the force of the wind. 

Lillenthal oo bia fljing m&chiDe. 

Sudden gusts were particularly dangerous and might cause the 
whole machine to turn over. He found a maximum area of 150 
square feet to be suitable for his sails, with a span from tip to 
lip of 23 ft. Anything bigger than this only caused loss of 
stability. Landing was also a difficult operation ; he said that 
he was often obliged to perform a kind of wild dance in order to 
keep his equilibrium. Still he generally came without accident 
to the ground, though he felt to have very imperfect control over 
his movements. He started by thinking he could do what was 
necessary by shifting the position of hia body, and in this way 
he altered the position of the centre of gravity. This worked 


well BO long as the sails were small, bat he was driven to increase 
their size. He therefore made an apparatus, which had a sail 
both on the left and on the right ; the area of each was 97 square 
feet, and the span from tip to tip was 18 ft. In this case, the 
old method of shifting the position of the centre of gravity 
worked well. If the wind lifted the wing on the left side, a 
slight change in the position of the body at once restored it to 
its original position. He was also able to rise to much greater 

Fm. 62.— Idlienthal 

ing machine. 

heights, and to float over the spot from which he had started, 
if the speed of tlie wind was greater than 30 ft. per second- 
In order to land in a gentle breeze, the machine, was point«d 
upwards by allowing the body to fall backwards. Ju^ before 
reaching the ground, the legs were thrown out, as if about to 
make a spring. In this way a very unpleasant shock was 
generally avoided, but if the wind was stronger, the apparatus 
would fall to the ground gently of its own accord. 

On his many trips Lilienthal always noticed the decided 
tendency of the wind to raise his machine. He also believed 


thiai the wind induced an eddying motion, similar to that noticed 
in the flight of birds, but the hill from which he started was too 
close to allow him to indulge in the execution of any such 
manoeuvres. His practising ground was generally in the neigh- 
bourhood of Berlin. He always started from a hill, and finally 
conBtructed one for his own purposes near Gross-Lichterfelde, 
50 ft. high and 230 ft. in diameter at the bottom. He gradually 
reached a certain proficiency in the art of flying, and thought 
he might safely try the effect of a small motor, which was to 
be used to flap the wings. He had a further scheme by which 
he altered the position of the rudder through a movement of 
the head, but unfortunately on August 9th, 1896, some mistake 
was made in one of his adjustments. When at a height of 
50 ft. the whole thing turned over and fell to the ground, 
Lilienthal being killed on the spot. Two years previously he 
had had an accident on the same spot, owing to the breakage 
of one of his arm supports ; at that time he escaped without 
serious injury. But the fate of this indefatigable man has in 
no wise discouraged his successors ; his work is being continued 
in many parts of the world. 

Percy S. Filcher made many machines of this kind, and was 
very skilful in their management. He employed the methods 
of a child's kite, and employed men to pull him by a rope in a 
direction opposite to that of the wind. In this way he often 
rose to heights of 60 feet. But he met with the fate of Lilienthal, 
and, falling from a height of 30 ft., sustained fatal injuries. 
Chanute and his assistant Herring made many attempts with 
aeroplanes in Chicago. Chanute introduced an improvement 
in the phape of an elastic rudder. This consisted of an arrange- 
ment by which the inclination of the sails was adjusted to meet 
the pressure of variable gusts, and he made a great number of 
trips in aeroplanes of this description. Herring continued the 
experiments and added a motor. This was placed between two 
of the exposed surfaces of the machine, and with its aid he 
actually succeeded in flying, but the flight only lasted a few 
seconds, as the air was not sufficiently compressed. 
Hargrave was the inventor of a peculiar but excellent type of 



kite, 8omew)iat of the form of a bos. But the brothers Wright 
far outstrip everybody else, if the reports of their doings ara 
true. The world was lately astonished at the news that they 
had formed a company in Paris, which was to buy their inventioD 
for the sum of ^40,000, and place it at the disposal of the 
French War Office. The Wrights then stated, in answer to 
enquiries, that they were proposing to sell it for the Butn 
inentioned in the report; but aa a condition precedent to the 
BBle, a trial run was to be made in the neighbourhood of Pans, 

Fio. 03.— Starting an aeroplane. 

and was to show a speed of 30 miles an hour. Wilbur and 
Orville Wright are natives of Dayton, Ohio, and having enjoyed 
a good technical education and started a successful bicycle 
factory, they turned their attention to the problem of flight. 
They had the help of Chanute, and followed Lilienthal's plan 
of mastering the art of floating before trying the effects of a 
motor. With a wind blowing at the rate of 26 ft. a second, 
they were able with their apparatus to maintain themselves for 
a while in the air. Tlie experiments were carried out on the 
dunes aloug the shore of the Atlantic, where a steady wind blows 
the whole year round. 


They first directed tbeir attention to three pointB : (1) whether 
it is better to let the driver stand or lie down ; (2) whether 
stability is better ensared by special steering devices or by 
shifting the position of the centre of gravity ; and (S) what 
effect is produced by a radder placed at the front of the machine. 
The eiperiments were always carried oat in the same order, and 
the machines were first tested like kites at the end of a rope. 

After any necessary changes had been made and a' certain 
modicum of stability seemed assured, one of the brotliers laid 
himself at fall length in the machine. The work then continued 
in the same keen and determined way ; neither the expected nor 
the unexpected was sufficient to upset their mental balance. 
The form of the aeroplane was almost exactly the aame as that 
of Channte and Herring. Two surfaces of the nature of sails 
were arranged, the one above the other. At first they were 
slightly concave ; but this was abandoned in favour of fiat 


surfaces. The driver lies at full length on the lower sail in a 
space arranged for this purpose. In front of him is the rudder 
controlling the elevation. The vertical rudder for directing the 
horizontal motion is behind him. The design used in 1900 had 
a sail area of 172 square feet ; in 1901 and 1902 this figure was 
increased to 812, and finally, in the year 1903, when the motor 
was first introduced, it was again raised to 625 square feet. In 
1902 the length of the sails in the direction of motion was 
5 ft. 8 in., and their breadth 85 ft. The vertical rudder for 
horizontal movement had an area of 14 square feet, and was 
placed at the back and shaped like a bird's tail, the total 
weight of the machine being 117 lbs. The course was inclined 
at an angle of 7 degrees to the horizontal, but a slight accident 
led to an alteration of the back rudder. This was reduced 
to half its former size, and the stability was then found to be 
all that could be desired. The angles of flight varied from 
5^7 degrees, the longest distance travelled being 200 yards 
in 26 seconds. 

They then made an important step forwards and turned their 
aeroplane into a flying machine by using a motor, which was 
built in their bicycle factory from their own designs. It was 
then arranged so as to drive two propellers at the back, and the 
weight of the whole machine amounted to 5^ cwt. The first 
trial was made against a wind blowing at the rate of 38 ft. per 
second, and the start was made from a railway track with the 
motor going at full speed. It rose upwards to a height of 10 ft., 
and after some irregular movements came to the ground. The 
longest distance travelled in 1908 was 850 ft. in 59 seconds. 
The trials were continued in the following year, and distances of 
800 and 400 yards were covered. In September, suflScient pro- 
gress had been made to enable them to turn round slight bends, 
and on the 20th they succeeded in returning to their starting 
point. All these journeys were naturally undertaken with a 
driver on board ; latterly small loads of iron rods were also taken, 
which gradually rose to 2 cwt. The following is a statement of 
the best results obtained in 1905, On September 26th, a dis- 
tance of 11 miles was covered in 18 minutes 9 seconds. The 




length of the journey depends on the amount of benzine carried ; 
in this case it had heen supposed to be capable of lasting 40 
minutes. On September 29th, 12 miles were covered in 19 
minutes 66 seconds ; on October 3rd, with a larger reservoir for 
the benzine, 15 miles were done in 26 minutes 5 seconds; on 
October 4tb, 21 miles in 33 minutes 17 seconds, and on the 
following day, 24 miles in 38 minutes 3 seconds. 

Captain Ferber, of the Balloon Corps, and the editor of 
L'Aerophile put themselves in communication with the 

—Archdeacon's eiperimenU on the Seini 
(Prom Moedebeck'i " Dia LuIUehllUiTt") 

Wrights in order to find out the exact position with regard to 
these trials. The answer which Ferber received tended to show 
that there had heen much exaggeration in the reports. Chanute, 
however, stated in a letter that he had witnessed a trial trip over 
a distance of 500 yards, and had heard that great distances had 
been covered ; but a journey, which was to cover 40 miles in an 
hour, had been abandoned on account of the strong wind blowing 
on the day of his visit. In so far as the outsider is concerned, 
not the least mysterious part of the affair seems to be the 
proposal to sell the invention to the French Government. 
The work done by Professor Montgomery in California does 



not seem to have been so successful. He built an aeroplane for 
the Jesuits of the monastery '* Santa Clara." His intention was 
to raise it to a height of about 2,500 feet by means of a MonU 
goljiere^ and then to cut it adrift. On July 19th, 1905, after a 
series of successful experiments, one of the sails broke after the 
machine had started from the balloon. The apparatus fell 
directly to the ground and the driver was killed on the spot. 

Mention must also be made of the work done by Archdeacon 
in Paris. His aeroplane was towed by a motor-boat, travelling 
at 25 miles an hour, in a direction opposed to the wind, which 
was blowing at 4 miles an hour. It was constructed after the 

Fio. 66. — LaDgley's flying machine on the Potomac. 
(From the lUvatrierU AerowiLuiitcht Miiieilungtn,) 

fashion of a Hargrave kite in Surcouf's balloon factory. At the 
front there were two sails, 88 ft. by 6 ft. 6 in., and at the back 
two other sails with an area of 220 square feet; the rudder, with 
an area of 82 square feet, was placed at the front. The weight 
of this machine without driver w^as 6 cwt., and it was mounted 
on two small boats after the manner adopted by Kress. 
Generally speaking, it turned out to be very stable, and rose 
to heights of 160 ft. But it often fell into the river, over which 
the flight took place, and on one occasion it turned over com- 
pletely, sustaining serious damage. 

Lately a good deal has been heard of another type of flying 
machine. It is proposed to run the machine along the level by 
the aid of a motor until such a speed is reached that the 


compreBsion of the air suffices to lift it upwards. All these ex- 
periments tend to show that the erux of the problem lies largely 
in the creation of sufficient kinetic energy to give the machine a 
start. For the sake of completeness, two other types ought to 
be mentioned, viz., the paddle-wheel and the sail-wheel. Eoch 
of Munich advocates the former ; the propulsion is effected by 
paddle-wheels, placed below the sails of the machine. Professor 
Wellner advocates the latter, which consists in mounting the 

^j'.-F nk 

Tia. 67.— Wellner's flying machine. 

sails on the surfaces of revolving drums, and thereby causing 
them both to support and propel the load. 

Even if the reports from America about the Wrights are 
largely discounted, it is quite certain that substantial progress 
has been made of late years in the design of flying machines. 
It therefore does not seem to be unduly optimistic to suppose 
that the twentieth century is likely to solve this problem and to 
produce a flying machine, capable of doing work of a really use- 
ful nature. The difficulties mainly lie in producing flight in 
the direction of the wind, and still more, in a direction at right 
angles to that of the wind. It is far easier to move against 
the wind in a machine of this kind than in a dirigible 


The kite was probably invented at least 200 years before the 
birth of Christ, and seems at that time to have been used for 
military purposes. The Chinese general, Han Sin, brought his 
forces to the relief of el 
beleaguered town, and 
by means of kites he is 
said to have signalled 
to the inhabitants, 
showing them the direc- 
tion in which he was 
making an under- 
ground passage in to 
the town. The peculi- 
arities of kites must 
therefore have been 
understood at that 
time.' Some 800 years 
later another Chinese 
general used them to 
help him to effect a 
junction with his allies. 
He was besieged in the 
town of King- Thai, and 
sent out a number of 
kites with a request 
for speedy relief, the position of the kites showing the most con- 
venient side of the town for an attack. In later years the English 
and the Spaniards are said to have used them for similar purposes. 
Moedebeck made enquiries as to their use in Japan. It appears 
» I-.!cornu, " I^s Cerfs-Volanl?," Faria. IW2. 



that a fisb-Bbaped kite, called a " May carp," U hoisted on the 
tops of the houses on May 5tih, if the father of the family has been 
blessed with a son during the preceding year. This takes place 
during the observance of the May festival, which was founded about 
£00 A.D. Curiously enough, a very similar device has been invented 

Fia. flfl.— HwgrBTe kite. 

by Mr. Patridt Y. Alexander during the last fen years, and is called 
by him an aerosack. It may be described as consisting of a pillow- 
case, into the mouth of which a hoop has been inserted. If it is 
hoisted on a stick and kept with its month towards the wind, it 
behaves in exactly the same way as the Japanese carp. 

The ordinary kite must 
have been well known at 
the time when Benjamin 
Franklin applied them for 
electrical purposes. He 
had proved that long 
insulated metal rods were 
able to collect electricity 
from the atmosphere, and proposed to conduct it from the clouds to 
earth. In 1752heconstrncted kites, such as were used by children ; 
he covered them with silk and added a metal point at the top. 
About the same time Romas did likewise. The metal tip was 
connected in one way or another with an insulated conductor, from 

Fio. 70.— Other sliapea o( Hargrave kitea. 


which it was possible to extract sparks 10 ft. long. Many scientific 
men followed in his footsteps, and applied his methods to the 
study'of atmospheric electricity, and in Philadelphia a clab was 
founded for the purpose, called " The Franklin Kite Club." 

The first scientific investigation into the problem of the kite 
was published by the celebrated mathematician Euler in 1756 ; 
and lately the American meterologist Botch, director of the 
Blue Hill Observatory at Boston, has made further publications 
on the subject, with the help of his assistant, Marvin. The part 
which is played by kites in meteorology at the present day will 
be discussed in a later chapter, and they are also usefully applied 
for military purposes in a variety of ways. It has been thought 

Fio. 71, — Various forms of kites. 

that it might be possible to use it as a substitute for the captive 
balloon in windy weather, and it this should be possible, it might 
displace it altogether. Kites would be far cheaper, and have the 
further advantage of being independent of gas generators and of 
the nature of the country in which the ascent is made. They 
are also used by the military for the transmission of signals, and 
for photographic purposes. The progiess that has been made 
bus been largely due to the fact that there has been little 
difliculty in raising funds, and succet^sful experiments have been 
carried out by Eotch, Marvin, Fergusson, Clayton, Eddy, andWiae. 
From the modern point of view there are three main forms of 
kite ; firstly, the Malay kite, as improved by Eddy ; secondly, 
the Hargravo kilc, which appears in all sorts of shapes ; and 



thirdly, the kee^liite, invented by Clayton. The first two types 
are fairly well knovn, but the keel-kite is not in the same 
position, and therefore requires to be more fully described. A 
framework, built up out of wood and phosphor bronze wire, is 
covered by cambric and used as a keel. It is mounted on a 
piece of pine wood, and the rest of the kite is constructed in 
the usual way. The only difference lies in the possibility 
of slightly altering the angle of inclination of the sails. By 
means of a spring, it is possible to lessen the inclinatioa 
of the exposed surfaces to the wind, so that it flies along more 

Fio, 72.— Codj'B kite. 

easily under a diminished pressure. This is a real improve- 
ment. On the one hand, the vertical position of the kite is 
more stable, and on the other, a serious accident is rendered 
more improbable. 

In mounting to great heights it is necessary to use a light 
kite. In consequence, it is not likely to be very strong. It has 
often happened that a kite of this kind has been destroyed by 
the wind, which may be blowing strongly at a great height with- 
out being very noticeable at the ground level. This is a common 
occurrence in meterological work. As it is not possible to reach 
great heights with one kite, it is usual to put several on the same 
cord, one behind the other, and sometimes as many as nine are 



joined together in this way. A kite of this kind is quite able to 
support the weight of the rope and recording instruments. 

The Americana have applied them to many military parpoees, 
and Lieutenant Wise has carried out a great deal of work with 
this object in view. It is particularly well adapted for siimalliag. 

An absolutely calm day or night is a very rare occurrence; and 
it is nearly always possible to send up a string of kites to a height 
of a few hundred feet. Signalling ciin therefore easily be carried 
out, either by hoisting fluids in the daytime, or lights at night. 
ArVith regard to liglits, the simplest plan in to use different colours, 
and to vary their position with regard to one another. Bengal 
lights of different colours eniild also he used to convey intelligence. 



DotibtUsB the best thing in this respect is the electric light, which 
can be switched on and off from below. If electric lights are 
arranged, one above the other in separate compartments, and 
ehaded b; glaesas of different colours, a message can be signalled. 
The Morse code could always be used by showing the lights for 
longer and shorter intervals. Tests have shown that the electric 
light is clearly visible over a distance of 12 miles, so that signals 
of this type would be usetnl over that range. 

Attempts have been made in America as well as in England 

Fio. 74.— Kite (or 


lO. 76. — tjignalling hj a 
lights trom ft kite. 

and Bussia to hoist an observer in a kite. The first load was a 
dummy of suitable weight, and on January 27th, 1897, an 
American officer went up. The velocity of the wind was 23 ft. 
per second. Four Hargrave kites were UBed, of different sizes. 
The top one had a surface of 20 sq. ft., the next of 39 sq. ft., the 
next of 8G sq. ft., and the lowest of 155 sq. ft. The total area 
was about 800 sq. ft. To the lowest kite a very primitive seat 
was attached, made of bamboo rods. The kites weighed 58 lbs., 
the cord 20 lbs., and the passenger 148 lbs. On this occasion 
Lieutenant Wise rose to a height of 50 ft., and could see over the 



tops of the houses. He thought he could have risen still higher, 
but contented himself with this as a first attempt. 

Millet has proposed an arrangement b; which the basket for 
the passenger is fastened to a single kite of curious design. The 
advantage of bis scheme lies in the possibility of convertiDg the 
apparatus into a parachute, in case the rope should break or be 
shot away. For this purpose it would be necessary to cIoBe 
down the sails at the side, and so create an enclosed space capable 
of compressing the air in its 
fall. The driver is also able to 
regulate the height of ascent. 
The basket is hung from a pulley 
and can be drawn up by ropes so 
as to come nearer to the kite. 
In this way the position of the 
centre of gravity would be 
changed, and the inclination of 
the sails to the wind would be 
correspondingly altered. The 
reaction due to the wind would 
therefore change, and would 
tend to produce a rise or fall, 
according to the circumstances. 
Similar kites have been in> 
■ vented by Major Baden Powell, 
Lieutenant Ulljanin, and Cap- 
tain Bolscheff. In August, 1825, 
I said to have driven three passengers 
n a carriage drawn by two kites. The 
1 with paper ; it was 20 ft. 
Above this was a smaller 


a man, named Pocock, is 

from Bristol to London ii 

main one whs made of muslin covei 

long, and rose to a height of 160 feet, 

kite that could be so steered as to help the other to surmount 

trees and obstacles. AVith a favouring wind, Pocock was often 

able to cover twenty miles in an hour, and to beat all other 

vehicles that competed against him. 

Much interest was taken in the performances of Cody, other- 
wise known as Buffalo Bill. He had a light folding boat, 13 ft. 



long, and 3 ft. broad, which was covered with cambric, and bad 
a Bpace in the middle to accommodate the passengers. A kite, 
flying at the height of 560 ft. was fastened to the top of the 
mast, and pulled the boat along. On November 6th, 1903, he 
succeeded in crossing from Calais to Dover in 13 hours. A 
rowing boat accompanied bim, with a crew of five men, but the 
pace was too great for it to keep up with him. 

Fig. 77.— H[llet'8 kite carrying obeerven. 

Kites have often been proposed for the purpose of saving life at 
sea. They have been used for the purpose of throwing liiiea on 
board a wreck, or from the ship to the land, and many cases are 
on record where they have served a useful purpose in such 
emergencies. It may also play its part in Polar expeditions. 
Quite apart from its use for meteorological observations, it might 
l)e used to drag sledges, and so take the place of dogs. There 
are few things capable of such varied application as the kite. It 
may assume almost any shape, and every fresh enthusiast seems 
lo evolve something new in the way of design. 



The first mention of parachutes is to be found in the 
writings of Leonardo da Vinci, and Fauste Yeranzio seems 
to have risked his life at the work. Joseph Montgolfier also 
made similar experiments at Annonay before turning his atten- 
tion to the balloon. Sebastian Lenormand made a descent froin 
a tree in a parachute in 1788 ; but his later experiments were 
confined to dropping animals, which were placed in a basket 
attached to the parachute. Blanchard took up the matter pro- 
fessionally, and made a good deal of money by inviting the 
public to witness his performances. Garnerin was taken up by 
a balloon on October 22nd, 1797, and after the supporting rope 
was cut, he fell 8,000 ft. to the ground. In 1886, Cocking used 
an inverted form of parachute. He was taken up by Green in a 
balloon to a height of 8,000 ft. and then cut adrift. The frame- 
work of the parachute collapsed under the pressure of the air, 
and Cocking was killed on the spot. 

For balloon work, parachutes are of no use ; they are merely 
suitable for country shows. Balloonists are often asked whether 
they take parachutes with them in case of unforeseen disaster. 
The fact is that any such precaution is unnecessary. Suppose 
a balloon were to lose its gas suddenly. It would fall at the rate 
of about 20 ft. per second, because the balloon itself would 
behave after the manner of a parachute, and if the velocity 
should rise to 80 ft. per second, as happens occasionally in 
stormy weather, this is due to the fact that a downward wind 
helps to increase the speed. 

Professor Koeppen has collected some figures from which he 
concludes that too low an estimate has generally been put on 
the time occupied in falling. Eobertson is said to have fallen 
10,000 ft. in 35 minutes, which is at the rate of 4 ft. 9 in. per 


aecond. Fran Poitevin fell 6,000 feet io 45 minatea ; bar 
hueband took her up in a balloon, and wben she reached the 
ground, he was in the act of packing it up. Dr. Briiuler has 


Fig, 78. — Cocking's pnrncliulc. 

sliown that with pressuree on the surface of the parachute of 
0-2, 0-4, 0-8. 1-G and 3-2 lbs. per sq. ft. respectively, the 
correspondingly final velocities will be 7'87, ll'S, 164, 22'(i, and 
32'8 feet per second. It is very important to provide a small 
opening at the top of the parachute, so that the compressed air 



has some chance of escapmg. Otherwise a vibrator; motion, 
like that of a pendulum, may be set up, and in an extreme case, 
the parachute may be turned over. Poitevin's parachute had a 

t'rSuleia Kiitbe Taulus with 

diameter of 40 ft., with an opening 6 ins. acrosB at the top; its 
weight was 66 Ihs. 

The latest novelty is a double parachute, invented by the 
balloonist Lattemann, and used on lier many descents by 
Frtiulein Eiithe Paulus. They are rolled up, the one under the 
other, and hang from the balloon. The upper one opens as soon 
as the spring has been made, and the lower one comes into 
operation as soon as the motion becomes steady. If a double 
parachute is used, it is necessary to make the descent from a 


great height. FrJiQlein Paulas has made sixty-five descents ia 
the parachute without serious injury ; but it must be admitted 

Fio. 81.— Full ot a parachote. 
that the journey has not always been a very smooth one. A 
certain amount of grim determination is necessary for this kind 
of work, and the profession is never likely to be overcrowded. 






GiROUD DE ViLLETTE made an ascent in one of Montgolfier's 
captive balloons in 1783, and pointed out the obvious advantages 
which must result from its use in war. Meusnier was induced by 
these considerations to devote much time to the study of dirigible 
balloons ; his work has already been noticed in an earlier chapter. 
In 1792, the Committee of Public Safety was urged by Guyton de 
Morveau to consider the question of using balloons in the defence 
of the country. He had already built a dirigible aerostat for the 
Academy of Dijon, and was able to convince his colleagues as to 
their probable value. Indeed in the next year at the siege of 
Cond6, attempts were made to communicate with the besieged by 
means of pilot balloons. But they were badly constructed and 
fell into the hands of the enemy. 

The experiment was not repeated exactly in the same form. 
It was now proposed to use captive balloons, and Guyton de 
Morveau was instructed to proceed in the matter. It was, how- 
ever, laid down that no gas was to be used that required sulphuric 
acid for its production. In those days, sulphuric acid was com- 
paratively a rare product, and the making of gunpowder absorbed 
all the sulphur that was available. Guyton de Morveau turned 
to the chemist Lavoisier, who had discovered a new method of 
making hydrogen. With the help of a physicist named Coutelle, 
they proceeded to construct an oven, which was to be used for 
preparing hydrogen by passing steam over red hot iron. This 
was soon ready, and a balloon, 30 ft. in diameter, was filled with 
the gas in the gardens of the Tuileries. The experiments 
succeeded so well that Coutelle was sent on a mission to General 
Jourdan, who was commanding the armies on the Sambre and 
Maas, with a view to inducing him to make use of a captive 
balloon. It so happened that when he arrived in Belgium, he 



was received by a member of the National Assembly. To him 
the idea oE a military balloon appeared bo ridiculous that he 
threatened to shoot Coutelle. General Jourdan, on the other 
hand, was much struck by the plan, and instructed Coutelle to 
return to Paris and procure the necessary materials. The castle 
at Meudon, which served as barracks for a diviaion of artillery, 
was utilised as the first regular balloon factory. Great skill was 
shown over the work, and the requirements of a military balloon 
were very carefully considered. The size was calculated on the 
assumption that it was to carry two passengers. A very light 
material was nsed for the envelope, and it was made airtight by 
a special kind of linseed 
oil varnish. This varnish 
tamed out to be excellent, 
and it is therefore a mis- 
fortune that the mode ot 
its preparation should be 
one of the lost arts. 

In a few months 
Coutelle was able to invite 
the committee to inspect 
the first war balloon ever 
made. It was held cap- 
tive by two ropes. Com- 
munication with the ground was by means of a speaking-tube, 
or by flag signals. A long message was written on paper and 
then sent down in a small sand-bag, along one of the ropes. 
It is curious that drawings are nowadays sent to the ground 
in the same way, the only difference being that small bags are 
used to which lead plates are attached; they are allowed to 
slide down the telephone cable, because the connecting rope is 
too far from the basket. The committee was so well satisfied 
with the performance of " L'Entreprenant," as the balloon was 
called, that Coutelle was appointed a captain, with instructions 
to form a balloon corps. At the same time he received the title 
of Director of the Aerostatic Experimental Station, with Conte 
for his assistant. The first balloon company on record came into 

Fio. 82. — Uethoda of traaBporting a captivi 
balloon. Od the left is eho?ni a menne o: 
protecting the ballooa from the wind. 


existenc« on April 2nd, 1794, ftnd consisted of & captain, a 
lieutenant, a sub-lientenant, a sergeant-major, 4 non-com- 
missioned officers, and 26 men, including a drummer-boy. The 
uniform consisted of a blue coat with black collar and facings, 
finished off with red braid. Their buttons bore the inscription 
" Aerostiers." A special uniform of blue colour was provided as 
a working costume, and they were armed with swords and 
pistols. The lientenant, named Delaunay, was a builder by trade, 
and turned out to be a very useful and practical man. Within 

of Sirassburg. 

a week of the formation ot the company they marched against 
the Austrians at Maubeuge, unaccompanied by their balloon, and 
came off with flying colours. Coutelle reported that his men 
were looked upon with contempt by the rest of the army, because 
they were mere artizans, and nobody understood in the least the 
nature of their work. He therefore begged the commanding 
officer to allow his men to have some opportunity of distinguish- 
ing themselves. The result was that the sub-lieuteuant was soon 
killed, and two of the men grievously wounded, but their bravery 
was now estabUshed beyond all dispute. The balloon soon arrived, 
and was filled with the gas from an oven that had been got ready 


in the meantime. The construction of the furnace will be 
described later. 

Coutelle undertook the first ascent in company with an officer 
amid the booming of cannon and the applause of the soldiers. 
They were able to report at, once as to the movements of the 
enemy, with the result that an officer of the general staff was 
ordered to make an ascent with Coutelle twice daily, and General 
Jourdan himself made several trips in the car. The Austrians 
objected strongly to this method of waging war. Not only were 
their plans known to the enemy, but their whole army had a 
superstitious dread of the new methods. Orders were therefore 
given that two 17-lb. howitzers were to open fire on it. This 
was done on June 13th, and for the first time in history cannons 
were directed against tbe aerial battleship. Coutelle greeted 
their efforts with the shout of "Vive la republique"; but noticing 
that their artillerymen were making good practice, he cautiously 
withdrew to a higher level out of range. 

Still it could be hardly said that the firing was wholly 
ineffective. It greatly annoyed the men who held the ropes of 
the captive balloon, and also did more material damage. Jourdan 
therefore sent for an experienced gunner from Lille, who declared 
that he would soon silence the fire of the enemy. However, the 
Austrians knew nothing of the moral effect produced by their 
guns, and thinking that they were producing no result, withdrew 
them in another direction. But the balloon did not altogether 
escape injury. It was blown by a strong wind against tbe church 
tower of Maiabeuge, and somewhat damaged. Moreover tbe gas- 
oven was out of order, owing to damage to some of the retorts. 

On June 18th Coutelle received orders from General Jourdan 
to join the army at Charleroi. In order to avoid loss of time in 
packing the balloon and building a new gas generator at Charleroi, 
he determined to send the balloon up in the air and have it towed 
over the distance of twenty miles, which separated him from his 
destination. Twenty guide-ropes were fastened to the balloon, 
halfway down the net ; all the instruments were put in the car 
together with the signalling flags. Coutelle then mounted the 
car, and the march began on a dark night through the outposts 

K 2 


of the Austrian army. It was necessary to avoid interference 
with the rest ot the French troops ; the rope-holders were there- 
fore obliged to march on opposite sides of the road, and this 
added greatly to the fatigue of the journey. Orders were given 
through the speaking tuhe from the car ; and the balloon was 
kept at anch a height that it just passed over the heads of the 
horses. After almost superhnman efforts on a scorching day 

11.^ Belle- Alliance I'lRti, Berlin, taken from balloon bja member of the 
I'nissian Balloon Corps. 

the balloonists arrived in fifteen hours at Charleroi, where they 
were received with open arms. Un the same evening an ascent 
was made, and on the next day Contelle had General Morelot as 
a companion in the car, where they remained for eight hours 
under the continuous fire of the Austrians. Morelot was able to 
see that it would be impossible for the town to hold out much 
longer, and therefore was on the point of ordering it to be taken 
by storm when the garrison capitulated. 

The balloonists were now ordered to proceed to headquarters 


at a place called GoBselie. This formed the middle of the French 
position, and an important battle was impending. On June 26th 
General Morelot went up in the balloon with Captain Coutelle 
before the beginning of the battle ; they rose to a height of 
1,800 ft., and in consequence of the clearneBS of the atmosphere 
they were able to report to General Jourdan as to all the move- 
ments of the enemy. Tlie Austrians tried to dislodge the observers 
by heavy firing; but they failed, although one or two shots 
passed between the car and the envelope of the balloon. In the 
afternoon they were ordered to attach themselves to the right 

Fio. 85. — Hel[iing lo land a balloon. 

wing of the army, and to lead the way by means of signals. The 
battle was finally won, and the generals expressed themselves as 
thoroughly satisfied with the work of the balloonists, to whose 
efforts the result of the day was largely due. 

The Austrians, on the other hand, were much disconcerted by 
the new methods, and recognised that the balloon was an insidious 
form of attack. They therefore announced that all balloonists, 
who fell into their hands, would be treated as spies. And after 
the battle of Fleurus they fell upon evil times. Coutelle marched 
with the army against Liege, but after reaching Namur, he was 
obliged to fall back on Maubeuge. A gust of wind had dashed 
the balloon against some trees, and it was found impossible to 


execute the repairs with the means at disposal. Goutelle there- 
fore returned to Meudon, where he made a new cylindrical 
balloon, called the " Celeste." It was immediately put to the 
test at Liittich, but turned out to be very unstable in a light 
breeze. It was therefore unsuitable for observations, and the old 
balloon, which had in the meantime been repaired, was once more 
brought into the field. It was put in a boat, taken across the 
Maas, and sent along the road to Brussels. 

Fate then overtook it a second time, before the gates of the 
town, where it was much damaged through being driven by the 
wind against a pole. Tiie repairs that were carried out in 
Brussels were unsatisfactory ; it had therefore to be sent to 
Meudon, and the balloonists were left without employment for 
many months at Aix-la-Chappelle. The time was not, however 
entirely lost, for improvements were made in methods of housing 
the balloon, and a kind of tent was built to shelter it from the 
force of the wind. 

In March, 1795, Coutelle was recalled to Paris, in order 
to carry out the formation of a second balloon corps in 
accordance with the decree of the National Convention of 
June 23rd, 1794. In addition to this, an ** Ecole nationale 
a^rostatique " was formed in consequence of the successes already 
achieved in actual warfare, and Conte, who was Coutelle's assis- 
tant, was placed in charge of it. The school was intended for 
the instruction of officers and men in the art of ballooning, and 
it was also proposed that it should undertake investigations 
into any suggested novelties. Conte set about his work with 
great zeal, and an efficient factory was soon organised, where six 
balloons were built. Two were sent to each of the existing corps, 
one was despatched to Italy, and the other was kept at Meudon 
for purposes of instruction. 

Trustworthy reports show that the material used for construc- 
tion was as good as that in use nowadays. A balloon intended 
to carry two persons to a height of 1,600 ft. had an envelope 
weighing between 180 and 200 lbs. The covering was made tight 
with five coats of varnish, and held so well that it was possible 
to use the same balloon for ascents, even after it had been filled 


for two months. The men were trained to the work of holding 
the balloon and pulling it in, and the school soon had a sub- 
director, a storekeeper, a clerk, and 60 men in training. The 
latter were divided into three divisions, each of which consisted 
of twenty men. One division was sufficient for holding a balloon ; 
each man had his own special rope to hold, which was fastened 
to the main rope, the same method being still employed at the 

FiQ. 8G.— A batloon about to land. 

present day. As the balloon was pulled down, the rope was 
wound round a drum. 

Conte also paid attention to improvement of the signalling 
arrangements. He introduced a system by which cylinders, 
made of black calico, stretched over rings, could be used to 
convey information. This was done by hanging the cylinders 
at a greater or Bnialler distance from the car, but this method 
was not very serviceable, as the wind was apt to scatter the 
cylinders in all directions with many entanglements. The gas 
generator was also improved, aa the result of experience. 


The Balloon Corps was quite independent of the school. 
Coutelle received the title of " Commandant/' and in virtue of 
his office commanded both companies. Each company had a 
captain, two lieutenants, one lieutenant acting as quartermaster, 
one sergeant-major, one sergeant, three corporals, one drummer, 
and forty-four balloonists. The second company was sent with 
the repaired " Entreprenant " to join the army on the Rhine. 
It was placed under the command of General Lefevre, who 
besieged the town of Mayence for eleven months, and recon- 
naissances by balloon were made daily till towards the end of 
the year. The aeronauts showed great skill on these occasions, 
which eventually received recognition even from an enemy who 
had declared that they would be treated as spies. On one 
occasion the Austrian generals sent word to the enemy to the 
effect that their observer was being sadly bumped by the heavy 
wind, and they thought it would only be reasonable to consult 
his feelings by pulling him in. But perhaps the advice was not 
altogether disinterested. Coutelle further states that he was 
sent under a flag of truce to the commander of the fortress, and 
that he was allowed to examine the fortifications as soon as it 
was understood that he was commander of the Balloon Corps. 
But the continual exposure did its work, and Coutelle had to be 
invalided home after recovering from typhus. 

With the loss of its leader came also the loss of good luck for 
the balloon. In the spring the " Entreprenant *' was on duty 
before Mannheim, when it was badly injured by the fire of 
the enemy. It was sent to Molsheim to be repaired, and then 
followed the army through Rastatt, Stuttgart, Donauworth and 
Augsburg, being hauled about from place to place while full of 
gas. Finally the return journey was begun, and the balloon 
was packed up and sent to Molsheim. Morelot's successor. 
General Hoche, took no interest in the balloon, and left it 
behind at Strassburg. He also sent a letter to von Wetzlar, the 
Minister of War, on August 30th, 1797, to the following effect : — 

** CiTOYEN MiNiSTRE, — I beg to inform you that the army on 
the Sambre and Meuse has a company of balloonists, for which 


it can find no nse ; perhaps it would be better to let it join the 
seventeenth military division, where it would be nearer the 
capital, and bo in a better position to do useful work. I there- 
fore ask permiseion to be allowed to dispose of the services of this 
corps in the manner suggested. 

" L. HOCHE." 

No notice appears to have been taken of this letter, and the 
corps therefore remained at Molsheim. 

It is now necessary to describe the fortunes of the first corps, 
which had joined the army on the Sambre and Meuse, and had 

and " L'lntr^pide " under the 

FlQ, 87. — Kite-balloon at anchor. 

the balloons " L'Hercule 
command of Captain 
I'Homond. There was 
much work to be done. 
They were used at the 
sieges of Worms, Mann- 
heim, andEhrenbreitstein. 
After the defeat at Wiirz- 
burg the corps retired 
within the fortress, and 
was imprisoned after it 
had surrendered to the 
enemy. At the end of the 
campaign they withdrew to Meudon, where the corps was enlarged 
and fitted out afresh. Contd persuaded Napoleon to use the 
company on his expedition to Egypt. But the first detachment 
had the misfortune to encounter a British man-of-war, and was 
duly sent to the bottom; the second was similarly captured. 
No feats of valour were therefore performed on the plains of 
Sgypt. Cont6 was, however, appointed to the general staff, 
where his sound sense and technical ability were much appre- 
ciated. On the occasion of a fete given by Napoleon at Cairo 
the balloonists sent op a Monigolfih-e, 50 ft. in diameter, and 
adorned with the " tricolore." This was supposed to be likely to 
instil a feeling of dread in the native mind, but it was largely 
without effect. 

On his return in 1798 Napoleon closed the ballooning school, 


and on January 18th, 1799, he disbanded the two companies. 
The balloons and their appurtenances were sold, with the 
exception of some things that were sent to Metz for storage. It 
has been already mentioned that Napoleon ceased to take any 
practical interest in ballooning after the day on which a balloon, 
sent up in his honour, was said to have fallen on the tomb of 
Nero. Forty years were to elapse before the Balloon Corps was 
revived. In 1812 a plan was mooted in Russia to use the balloon 
for military purposes. A German mechanic, named Leppig, 
proposed to the Russian Government that he should be allowed 
to construct a dirigible balloon. It was to carry fifty soldiers 
and a quantity of explosives, which were to be conveniently 
dropped on the heads of the enemy. It was intended to carry 
on the work with the greatest secrecy, and to place the factory 
in the village of Woronzowo, near St. Petersburg, which was to 
be isolated from the rest of the world by a kind of blockade, 
organised by 160 foot soldiers and 12 dragoons. Eventually 
two small balloons were got ready, each carrying two men; it 
took six days to fill them instead of six hours, as the inventor 
had promised. The trials failed miserably, and the inventor 
was cast into prison. Thus ended an experiment, which had 
cost £10fiOO, and no further work on ballooning was done in 
Russia till the year 1870. 

In 1815 Carnot caused observations to be made from a balloon 
during the siege of Antwerp, but nothing is known as to the 
results. During the campaign in Algiers a private balloonist, 
named Margat, was engaged to follow the army, but his balloon 
was never put on shore. In 1848 the insurgents in Milan 
devised a new use for pilot balloons, which they placarded with 
a proclamation of the Provisional Government, and in the 
Franco-Prussian war the French dropped a number of pro- 
clamations on the heads of the Prussian soldiers by the same 
means. During the siege of Venice the Austrians, in 1849, 
loaded small balloons with bombs, which were to be fired by a 
time-fuse and fall on the heads of the enemy. These balloons 
were naturally sent up without passengers, and it was expected 
that the wind would carry them in the desired direction. But 


this it failed to do, with the result that the bombs were discharged 
in their own ranks. Experiments on these lines were therefore 
discontinued till 1854, when a similar attempt was made in the 
arsenal at Yincennes with negative results. 

In 1859 Napoleon III. procured a large silk Montgoljiere from 
Italy, holding 28,500 cubic feet. It was handed over to a man 
named Nadar, who had done much photographic work from a 
balloon, and he made an ascent at Castiglione, accompanied by 
Godard, the balloon manufacturer. But they failed to accomplish 
anything noteworthy, and the same result attended their efforts 
on another hydrogen balloon, specially sent from Milan. 

Balloons were, however, largely employed during the American 
Civil War, when Professor Lowe, of Washington, went to the 
seat of war, and placed himself under the orders of General 
MacClellan. A man named La Mountain went up in one of the 
balloons, and drifted away in the direction of the enemy's camp. 
After making his observations, he rose higher in the air, and 
found a current which brought him back again. An aeronaut, 
named Allan, went up in the other balloon, and reported 
telegraphically to headquarters. Lowe also sent telegrams direct 
to Washington by making connection with the overhead wires, 
and the artillery also received signals from the balloon. Lowe 
was able to give them useful information as to the position of 
the enemy's batteries, and also as to the effect produced by their 
own firing. Strong winds often prevented ascents, and some- 
times it was not possible to reach a sufficient height to see all 
that was wanted. Still, MacClellan was well satisfied with the 
results, and requested the War Office to despatch four more 
balloons. On the retreat from Bichmond to the James Biver 
the General lost all his baggage, together with the balloons and 
gas-generators. The balloonists' occupation was therefore gone. 

In England similar work was done in utilising the balloon for 
scouting purposes. Much was done at Aldershot, but no special 
corps was formed at that time. 

In 1866 balloons were used in the war between Brazil and 
Paraguay. General Caxias sent up a balloon to reconnoitre on 
the road leading through the marshes of Neembucu ; it was under 


the guidance of a French aeronaat, but was accidentally burnt. 
It has generally been assumed that fires and other mysterious 
forms of explosion must be caused by flames coming in contact 
with the main envelope. But it has lately been found that this 
was not always the case, and further investigation seemed 
necessary. It now appears that electricity is the most probable 
cause of these disasters. A balloon descending from a height is 
charged with electricity, which may be discharged through the 
iron parts around the valve. The spark which follows may 
set fire to the explosive mixture which would collect near the 
valve, and in this way many accidents of a mysterious nature 
may very possibly be explained. Soon after the above incident, 
Caxias discharged the French aeronaut, as it was said that he 
was in the pay of the enemy. An American balloonist from Rio 
de Janeiro was therefore pressed into the service, and several 
balloons were placed at his disposal. Information of a useful 
nature was soon received, and a practicable path through the 
marshes was then found. But General Caxias found the balloons, 
and more especially the gas-generators, very awkward in active 
campaigning, and soon dispensed with their services. 

In France attempts were made in 1868 and 1869 to use 
balloons for signalling purposes at some of the naval stations. 
At Cherbourg small cylinders were hung from the balloon as 
signals, and at night projectors were used. But the results were 
rather unsatisfactory in windy weather. Lights were used to 
signal from balloons during the siege of Paris, and according to 
report the method gave satisfactory results. 



The English balloonist Coxwell was entrusted by the Germans 
with the formation of two balloon detachments with all the 
necessary tackle. Colonel Josten and a lieutenant commanded 
the two companies, each consisting of 20 men, and Coxwell sup- 
plied two balloons, having capacities of 40,000 and 28,500 cubic 
feet respectively. They were put to work in the neighbourhood 
of Cologne, and did well, except in rough weather, when it was 
evident that 40 men were insufficient to hold them. It was 
therefore determined to form the men into one company, and to 
send them to the front at Strassburg with the smaller balloon. 
It was filled with ordinary coal gas, and one of the officers pro- 
ceeded to make reconnoitring expeditions up to a height of 
1,200 ft. Orders were then received to forward the balloon to 
Sufifelweiersheim. In consequence of the strong wind, it was 
necessary to empty the balloon after it had travelled a few miles, 
and the problem of refilling it then arose. This was by no 
means an easy task in the neighbourhood of Strassburg, and the 
necessary barrels were not to be found without great trouble 
But after four days' search in the enemy's country Lieutenant 
Josten succeeded in getting together 75 wine-casks of different 
sizes. Of these, 60 were used for generating hydrogen from 
sulphuric acid and zinc, 12 served for washing the gas free from 
impurities, and the remaining three for drying the gas. The 
balloon was filled on September 24th in five hours, and in the 
afternoon an ascent was made by the two officers, who were 
later joined by an amateur from Cologne, named Dr. Mehler. 
The wind was too strong to allow of very exact work, and the 
balloon was consequently secured by a grapnel. Although every 
possible precaution was taken to shelter it from the force of the 
wind, it was nevertheless much damaged, all the gas escaping. 



Before it was refilled Strassburg had capitnlnted, and orders 
ware received to move forward to Paris. 

The march to Paris was a laborious operation. All available 
vans were placed at the dieposal of the commissariat department, 
and 80 none were left for the balloonista. As soon as they 
arrived in the neighbourhood of Paris it was found to be 
impossible to refill the balloon, and the company was there- 
fore disbanded on October 10th, 1870, the balloon being sent 
back to Germany. 

The French also found them to be of doubtful value. At the 
beginning of the war all proposals to employ aeronauts were 
refused by Lebceuf, the Minister of War. Even the offers of 
assistance from the celebrated scientific balloonist, Wilfrid de 
Fonvielle, were rejected, and it was not till after the fall of 
Sedan and the old regime that the experience of the beginning 
of the century was turned to account. During the battle of 
Valenton, on September 17th, 1870, four balloons were sent up. 
Several cft|>tive balloons were used in Paris, but they did little 
good, owing to the winter fogs. On one occasion uRfful informa- 
tion'witb regard to some trenching work done by the Germans at 


Pierrefitte was received. But on the whole the results were 
negative, and the military authorities sold their balloons to the 
Post Office. 

Paris was soon completely surrounded, and it became a matter 
of necessity to organise means of communication with the Pro- 
visional Government at Tours, and with the troops in the pro- 
vinces. A postal service by balloon was therefore arranged by 
Rampont, who was at the head of the Post Office. Balloon 
workshops were constructed under the control of Eugene and 
Julius Godard at the Orleans Railway Station in Paris ; another 
was similarly organised at the Northern Station by Yon and 
Camille Dartois. The balloons were to have a capacity of 
70,000 cubic feet, to be made of the best varnished cambric, 
to be provided with a net of tarred rope, and a car capable of 
seating four persons. All accessories were to be provided by the 
contractors in the shape of grapnel, valves, ballast, etc., the 
whole to be handed over ready for actual work. They were to 
be delivered on appointed dates, and a penalty of £2 a day was 
to be paid for any delay beyond the fixed time. Each balloon 
was to cost j£160, which was afterwards reduced to JE140 ; the 
driver was to be provided by the contractor for a payment of 
£12, and this was subsequently reduced to £6. Gas was to be 
charged as an extra, and payment was due as soon as the balloon 
was out of sight. Godard's balloons were coloured blue and 
yellow, or red and yellow ; those of the rival contractor were 
white. Drivers were found in the shape of marines ; but the cars 
for their accommodation were of the most primitive kind, sup- 
ported by iron carriers. The working of the valves and instru- 
ments was explained to them, and they were also instructed in 
the art of emptying ballast and throwing out the grapnel. 
Altogether 66 balloons left Paris. They contained in all 66 
aeronauts, 102 passengers, 409 carrier pigeons, 9 tons of letters 
and telegrams, as well as 6 dogs. Five of the dogs were sent on 
the return journey to Paris, but nothing more was heard of 
them. Fifty-seven carrier pigeons were all that reached the 
besieged city, and they carried 100,000 messages. Fifty-nine 
balloons did their work as arranged, five fell into the hands of 


the enemy, and two disappeared altogether, having most probably 
fallen into the sea. 

Some of the voyages deserve special mention. On Septem- 
ber 80th Gaston Tissandier threw down 10,000 copies of a 
proclamation, addressed to the German soldiers. It contained 
a demand for peace, stating at the same time that France was 
prepared to fight to the bitter end. Gambetta left Paris on 
October 7th, with the intention of organising a fresh army in 
the provinces, and intended to march to the relief of Paris. 
The balloon was unskilfully managed, and came to the earth 
close to the German outposts. At first it was supposed to be a 
German balloon, seeing that it was known that one was expected 
to arrive from Strassburg. This delay allowed them to throw 
out some ballast. They then managed to escape, but not before 
Gambetta had been wounded in the hand. 

On December 2nd, 1870, the celebrated astronomer Jansen 
left Paris in the balloon " Volta," taking his instruments with 
him. He was anxious to reach Algiers before December 22nd, 
in order to observe an eclipse of the sun. The English had 
offered to endeavour to get him a permit to pass through the 
German lines, but this he had refused. The quickest and 
longest journey was made by the " Ville d'Orleans " on 
November 24th. It left at 11.45 p.m., and reached Eongsberg 
in the province of Telemarken in Norway the next day at 1 p.m. 
On December 15th "La Ville de Paris" landed at Wetzlar in 
Nassau, and the " General Chanzy " on December 20th at 
Rothenburg in Bavaria. The remains of the latter balloon are 
now in the Army Museum at Munich. Naturally these sorties 
were not at all to the taste of the Germans, and Erupp was 
ordered to make a cannon suitable for bringing the balloons to 
earth. It was to be capable of being tilted almost into a vertical 
position, and to have a special gun-carriage fitted to it. But it 
was not a success and was soon relegated to the Zeughaus in 
Berlin. The outposts, however, were constantly on the look-out, 
and the result of their firing was to drive the French to start 
their balloons by night. 

The German artillery knew the diameter of these balloons to 


be 50 ft., and were therefore able to tell the distance approxi- 
mately. In this connection it may be well to explain the 
principles on which aim is taken at ballooQB. The difiScult; in 
hitting a captive balloon is not great ; it consists in determining 
the distance and the range of the gnn. The distance can be 

69.— Gun comitructed by Krupp for firing at ballcxins. 

estimated if the size is known. In that ease it must be examined 
throDgb a telescope provided with spider lines, and the angle 
at which a non-spherical balloon woald be standing mast 
be taken into account. For instance, a French spherical 
balloon has a capacity of 19,000 cubic feet, and a diameter 
of 83 ft. With the telescope, its apparent size would be 
measured in sixteenths, and with the aid of a table (which, 


by the way, is very easily remembered), it is possible to 
estimate the distance. The table is as follows, and gives 
the distances corresponding to known diameters, on the 
supposition that they subtend one-sixteenth on the spider lines 
oi the telescope: — 

A diameter of 8*8 yards corresponds to a distance of 8,000 

A diameter of 4*4 yards corresponds to a distance of 4,000 

A diameter of 5*5 yards corresponds to a distance of 5,000 

A diameter of 6*6 yards corresponds to a distance of 6,000 


A diameter of 11 yards corresponds to a distance of 10,000 

Wherefore, if the French balloon measures one-sixteenth on 
the spider lines, its distance would be about 10,000 yards. It is 
merely necessary to compare the apparent with the known 
diameter to get the distance of the balloon. 

Another very simple method is to take observations of the 
balloon from two points at known distances apart. If the results 
are graphically transferred to paper the distance can be measured 
off. Experience shows that this method is very simply applied, 
and gives results of value both for field batteries and for heavier 

Still it must be admitted that observations of this kind require 
a certain amount of time, and regulations are therefore laid 
down, prescribing a method which is applicable, even if the 
distance is unknown. Firing is to begin either with shrapnel or 
with shells at the longest possible range, in order to find whether 
the balloon is within range of the guns.^ In order to deter- 
mine the precise spot where the shell bursts, a number of 
observers must be sent out, and i-ange themselves on either side 
of the path of the projectile. These observers report whether 
the shot appears to have gone to the right or left of the balloon. 

1 " Mitteilungen iiber Gegenstiinde des Artillerie- und Qeniewesen8," Vienna, 
1906. Militdrwochenblatt, 1906, No. 11. 


The precise position can then be easily fixed, with the exception 
of one donbtfal case. This will be 
made clearer by a stady oi the 
diagram. The following cases may 
arise: — 

(1) From the point of view of the 
battery (B), of the left observer (L), 
and of the right (R), the smoke 
hides the balloon (1, 2, S). The 
shell has fallen short of the mark, 
and the range must be increased, if 

(2) The smoke appears to all the 
observers to be in a line with the 
balloon, but partly hidden by it (4, 
5, 6). Then the gun has been set for 
too long a range, and the shell has 
fallen behind the balloon. 

(8) The shell appears to L to have 
fallen on the right, and to R on the 
left of the balloon (10). Then it has 
fallen short. 

(4) The shell appears to L to have 
fallen on the left, and to R on the 
right (5, 9). Then the range has 
been too long. 

(5) Both observers report that it 
has fallen on the left or on the right. 
This is a doubtful case, and must be 
marked as such. 

In cases (S) and (4), the more the 
shot appears to one of the observers 
to lie to the one side, the greater is 
its actual distance from the mark. 
The tangent sight must then be put 
in position, and special attention must be given to the direction of 
the aim. Therefore as soon as it is found that the balloon is 

L 2 

Fio. 90.~Rketch illustrating the 
method of aiming at a balloon. 


within range of the gun, the sights must be so set as to con- 
tinually diminish the range, till it is found that successive shots 
fall, the one in front and the other behind the* balloon. It is thus 
possible to get the range within 100 yds. Care must also be taken 
to see that the shells burst above the balloon ; otherwise they 
would not produce any effect. To judge from trials that have 
been carried out in time of peace, it seems likely that a balloon 
would be hit within 10 minutes. Still, in dealing with one that is 
moving rapidly, it would not be quite so simple. Rifle fire would 
probably be harmless to a balloon. Up to a range of about 
1,600 yds. a volley might produce some effect ; but the balloon 
would, hardly be likely to be so near the lines of the enemy. 

After this digression, it may be well to describe further the 
events connected with the siege of Paris. The successful 
organisation of the post naturally drove the professional 
aeronaut to attempt greater feats, by returning to the 
beleaguered city from the outside. Gaston Tissandier therefore 
built a balloon in Tours, having a capacity of 42,500 cubic feet. 
With it he intended to return to Paris when the wind provided a 
suitable opportunity. Before it was ready, he heard that his 
brother had reached Nogent-sur- Seine in the " Jean Bart " from 
Paris. He immediately went to meet him, and brought his 
balloon to Ghartres. Unfortunately serious injury was done by 
a violent storm, and he had much difficulty in preventing it from 
falling into the hands of the Germans. 

Gambetta and Steenacker gave the brothers much assistance. 
Everybody was convinced they would succeed. One man indeed 
went so far as to give the key of his house to Tissandier, asking 
him to be good enough to go round and see that everything was 
in order. But unfortunately they failed. At Le Mans, the wind 
was for a long time from an unfavourable quarter ; when at last 
it seemed suitable, they were not ready to make a start. They 
finally left Rouen in foggy weather ; but soon came to the ground, 
and found they had been driven far out of the course. They 
tried again the next day, but with the same result. 

The Government in Tours had meanwhile determined to place 
some balloons at the disposal of the troops in the provinces. The 


I I 

I I 

8 I 


'* Yille de Langres " had been got ready in Tours, and was sent 
with the aeronauts Duruof, Berteaux, and some marines to join 
the army on the Loire at Orleans. The Tissandiers followed in 
the " Jean Bart." B^villiod and Mangin were sent to Amiens, 
and shortly before the declaration of peace, Wilfrid de Fonvielle 
with two balloons was ordered to join General Faidherbe. Many 
accidents happened in the storms of December, 1870, the balloons 
being often torn to pieces by the wind. The work of marching 
with the balloons, filled with gas, was very laborious, and super- 
human efforts were required to meet emergencies of various 
kinds. Still, it must be admitted that the value of the observa- 
tions made in this way was not great, though the possible value 
of military ballooning under favourable conditions was thoroughly 
recognised. It was therefore determined to form a balloon 
corps, and Steenacker was authorised to make the necessary 

In consequence, two divisions were formed. The one was 
placed under the command of the Tissandiers with the balloons 
''La Yille de Langres" and ''Le Jean Bart"; the other was 
under B^villiod and Poirrier, and had two balloons, each with a 
capacity of 70,000 cubic feet. Accommodation was provided in 
Bordeaux, and each division had the assistance of 160 soldiers, 
when necessary. General Chanzy took much interest in the 
work and even made some ascents, though his adjutant had 
declined the offer of a seat in the car on the ground of unneces- 
sary risk. When peace was declared, there was no further 
need for ballooning in its military aspect, and the corps was 




Thb great advantage which France had derived from the 
balloon postal service during the war was thoroughly appreciated 
both in Paris and the provinces. Moreover, the journey of 
Gambetta to Amiens in " L'Armand Barbes " was an event of 
great importance. The war would undoubtedly have ended some 
months sooner if he bad not succeeded in hjs work of organising 
resistance, and Gambetta*B feat would of itself have been sufficient 
to justify the existence of military balloons, even if the history of 
the war had no other sucoesBeBot the kind. The message 
delivered by an officer of the General Staff to General Chanzy on 
December 22nd, 1870, was also a matter of importance, seeing 
that it stated on good authority that Paris could only hold out 
for a month longer, unless very energetic measureB were taken. 

It is as well to remember that there are no means of preventing 
the departure of a balloon by night, whereas most other methods 
of communication are easily interrupted under the conditions of 
war. Even with a full moon, a yellow balloon is almost invisible 
at a short distance^ a fact which has been frequently noticed. 
But in order to derive the full benefit from ballooning, it is very 
necessary that the organisation should be complete even in 
times of peace. It is precisely the kind of work that cannot be 
developed to a state of efficiency during a war. There is much to 
be learnt which requires long and careful practice. During the 
siege of Paris, sixty-six balloons were sent up, but of these only 
about a dozen were in the hands of really experienced aeronauts.^ 
All the others were in the charge of marines, who worked with 
a right good will, but without any special knowledge. Towards 

^ The figures here given are more accurate than those which have been glren by 
other authorities, and embody the results of the latest investigations. 



the end of the siege coal was almost eshansted, coal gas was an 
Doknown eommodit;, and there was a general dearth of all suitahle 
appliances. These things were taken into account in organising 
the arrangements subsequently, and in 1874 the " Commission 
des communications a^riennes " was formed. Colonel Lauseedat 
presided over its deliberations, and was well acquainted with all 
the technical requirements of the problem. He was assisted by 
Captain Benard and Captain La Haje, whose work has beea 
noticed in an earlier chapter. The members of this committee 
met with an unfortunate accident in December, 1875, while 

Kia. U2,— Old miilhod of geneTating hydrogen. 

engaged on their duties in a balloon, built b; Tissandier, which 
fell'from a height of 750 ft. in consequence' of a defective valve. 
Laussedat, Mangin, and Benard escaped with broken legs, while 
the'remainder of the eight passengers had more or less severe 

Soon afterwards Laussedat reported his proposals to the 
Minister of War, and asked for the necessary funds to be placed 
at his disposal. Money was, however, forthcoming only to a 
very limited extent. Hitherto they had been allowed the sum 
of £32 a year, and they were probably surprised to find that they 
were now to be 'allotted the sum of £240 to meet immediate 
requirements. Still much good work was done. Benard had 
carefully considered the question of generating the gas, and had 


constrncted an apparatus for generating hydrogen from snlpharic 
aeid and iron, which worked well. In 1877 the castle at Chalais 
was placed at their disposal. Nearly a hundred years had elapsed 
since it was first put to a similar purpose, and Benard now 
equipped it with all the necessary appliances. He arranged a 
workshop, chemical and physical laboratories, gas generators, 
testing machines, and a meteorological observatory. It is 
astonishing to find what he was able to do. He had the assist- , 
ance of a professional aeronaut, a sergeant, four sappers, and a 
ropemaker, and between them they soon managed to construct a 
balloon. Laussedat indeed considered that he was too energetic, 
and proposed to apply to other parposes the sum of £8,000, which 

Fla. 93. — Modem gas waggon. 

the Government bad now allotted at Gambetta's suggestion. 
But Benard contrived to resist this pressure, and it was then 
arranged that he was to be allowed to proceed independently on 
his own lines. After an inspection by Gambetta, the Govern- 
ment voted money for the further development of the work. The 
establishment at Chalais- Meudon was enlarged, and Captain Paul 
Benard was ordered to give his brother sucli assistance as he 
required. Gradually the work proceeded, each company having 
three balloons ; the two main ones were to be suitable for use 
either as captive balloons or otherwise. 

The ordinary balloon, now employed, has a capacity of 19,000 
cubic feet and a diameter of 33 ft. It is intended to be filled 
with hydrogen, and to take two passengers to a height of 1,650 ft. 



The BO-called auxiliary balloon has a capacity of 9,200 cubic feet, 
carrying one person ; but it' has the advantage of being more 
easily worked. In addition there is a gasometer, with a capacity 
of 2,120 cubic feet, for the storage of hydrogen. However, in most 
cases cyhnders containing compressed gas are taken with the 
balloon in carts, and this dispenses with the use of the gasometer. 
For use in the forts, balloons with a capacity of 34,500 cubic feet 
are used, and can be filled with coal gas in case of need, though 
ordinarily they are intended to be used with hydrogen. The 
methods of construction will bo described later. 

Since 1680 the balloonista have always taken part in the 
manoeuvres, and it nas soon seen that the waggons were too 
cumbersome. It also required three hours to fill the balloons, 
and this would make them practically useless in an emergency. 
The system of gas generators was therefore abolished, in so far 
as their use in the field was concerned, and the English method 
was adopted, which conaisti in taking cylinders with compressed 
gas for the purpose. By these meana it is possible to fill the 
balloon in fifteen or twenty minutes. Sufficient gas to fill four 
balloons can be carried on eight waggons. Each waggon takes 
eight cylinders, weighing in all two tons ; a cylinder is one foot 
in diameter, 15 ft. long, and contains 1,250 cubic feet of gas under 
a pressure of 300 atmospheres. One waggon, with a total weight 
of rather more than three tons, will carry 10,000 cubic feet of gas, 
which is sufficieni to lill nu auxiliary 
atus was brouglit iiilo use during 
was divided into i»ii cohtmns. TL 


a certain number of officers and men go into training every 
year. Balloons were also used to search for Bubmarines, and in 
June, 1902, Lieutenant Baudie nas drowned near Lagoubran 
wbile engaged on a work of this kind. Tbe ascents were gener- 
ally made with a captive balloon, secured to the stern of the 
vessel, and in August the approach 
of the submarine " Gustave Zede " 
was discovered in this way. How- 
ever, in 1904 tbe marine corps 
was disbanded, a measure which 
called forth a certain amount of dis- 
approval, but was doubtless justified 
by the results of experience. Still 
the advantages to be derived from the 
use of balloons for reconnoitring pur- 
poses along the coast seem fairly 
obviona. It would tbua be possible 
to detect the approach of tbe enemy 
at a much greater diatance than 
would be the case if observations 
were only made from the ground 
level, provided, of course, that the 
weather was reasonably clear. 

Various alterations have lately been 
made in the general organisation of 
the French Balloon Corps ; and, in 
particular, a great improvement has 
been intvodufed by uiuking it alto- 
gether iiuldpdtident of any experi- 
mental work. Coneeijuciitly all their 
attention is devoted to instructing tbe men and increasing their 
smartness in ihe liclii. A special laboratory has been erected in 
Paris fur the bUiily of pioblema directly or indirectly connected 
vitb balluuuiii};, and for carrying out experimental work. The 
ntnl offices ai'e at CtjiLkis-Meudon, where instruction is given 
[ grades in tbe service, and where tbe main workshop ia 
Four couiiJanies are stationed at Versailles with the 



Fig. 94.— French method ol 

■uapending Ihe basket for 
Ml obaerver. 


UBnal number of officers and men, Eind there are also companiee 
at Verdun, Epinal, Toul, and Bellort, with all the necessary 
appliances. At Versailles, Montpellier, Arraa, and Grenoble the 
organisation is subject to the general control of the engineers, 
and would only become an independent unit in the case of 
mobilisation. In all these pl&cea manceuvres on a email scale 
take place every year. 

The equipment in the field is rather different from that used 
in the fortresses. In the latter, compressed gas in cylinders is 

FiQ. 1)5. — One of the balloons is pegged down in Ihe open field, 
atid tbe other is sunk [n a spcciallj prepared pit. 

not used ; it is generated from time to time as required. But 
waggons are also provided in the forts, and could easily be used 
in case of emergency. The provision of skilled aeronauts is 
also a matter of importance, and this is part of the work done 
at Chalais-Meudon, where every year a certain number of men, 
principally from the educated classes, are instructed practically 
and theoretically in the art. They receive the title of " Aero- 
naute brevete " after passing an examination, and are instructed 
to place themselves at the disposal of the authorities of a given 
fortress in the event of mobilisation. The French Balloon Clubs 
also receive aasistunce from the Minister of War with a view to 
placing the services of their^ members at the disposal of the 


country in case of need, and they receive leasonB in the art ot 
construction for this pnrpose. The French army therefore dis- 
poses of the services of a large number of experienced men, 
who eould, in case of 
need, do much useful 
work in the fortresses 
and elsewhere. It 
has both a civil and 
military organisation 
to procure a number 
of skilled aeronauts, 
and under these con- 
ditiona there should 
be a BufScient sup- 

The baUoonists, 
enrolled by Captain 
Renard, bad their 
first experience of 
actual warfare in 
1884 in Tonkin. 
General Courbettook 
a detachment with 
him under the com- 
mand of Captain 
Cuvelier, consisting 
of two officers, 13 
non - commissioned 
officers, and 23 men. 
The appliances were 
designed with a view 
to easy transport, 
and the gas was generated by heating granulated zinc with 
bisulphate of potash. The balloon, which was not of the 
normal type, took 9,200 cubic feet of gas, and a band-winch 
for controlling its movements was carried on the tool-waggon. 
The commanding officer reported that the detachment had 

'iG. 9(1.— Front and rt 
(Prom " DleOeschJcbU 


been strengthened by the addition at some artiUerymen and 
some coolies, and that good work had been dona. They were 
particularly asefol in finding a way throogh more or less track- 
less marsheH, where the cavalry were nnable to penetrate, and 
where small reconnoitring parties were very liable to be amboBhed 
in the dense bamboo lureste. At the bombardment of the town 
of Hong-Hoa the firing of the guns was directed from the 
balloon, and in the same way the retreat of the enemy was 
signalled, with the result that the order was given to advanee 
to the attack. In the following year, they were attached to the 
reconnoitring party onder General Negrier, who frequently 
mounted the car for purposes of observation. In all subse- 
quent coliinial ware the balloonists have been employed in the 
French army, as, for instance, in Madagascar in 1895, and Takn 
in 1900. 

Cases often arise in which there is no immediate use for the 
balloon on an expedition, and the time is therefore employed in 
photographic work, so that the country may be mapped out and the 
salient features of the landscape recorded in case they may be of 
service at a later stage of the operations. The photographs can 
also be carefully developed into maps, or they may be merely 
stuck together on a sheet of paper as a kind of rough gnide to 
any detachment that may have to pass along the road. This work 
has been found \)'i,v ii^«;ful in cuunlrit;;^ uf ^iduio uiap^i exist. 

The Minister of War ih salil to lie a&t^^^^^^ the results 
produced by biiliriorLiJ in colonial waru, 
ot their operatn'in (wliich is by no md 
Ukely to be still furlher develoijedand b 
of efficiency. 

In Germany :i B» 
experiments mil 
out unsatkfan 
founded in Bi' 
study of the qm 

' " Hit ficschieli 
lUbctl liy Uciseubot 


The origlDBl deUchment eoDBisted of thirty-three men and foar 
officers, vis., Captain Buchholz, and Lieutenants von Tschadi, 
von Hagen, and Moedebeck. Their first task was to arrange 
an experimental station for eaptive ballooiiB, to be used for 
artillery purposes. They bad the assistance of a professional 
aeronaut, named Opitz, and settled down to work at the Eastern 
Railway Station in Berlin, which was placed at their disposal. 
In this way they had a large hall as a kind of drilling-gronnd, 
the waiting-rooms, etc., being turned into workshops and barracks, 
and the platforms 
into ropemakers' 
nms. It was thought 
necessary to exercise 
the men without 
delay in the work 
of practical balloon- 
ing, and arrange- 
ments were therefore 
made to have the 
ase of a balloon for 
this purpose. This 
was done by agree- 
ment with a profes- 
sional aeronaat who 
made ascents at 
Schonebergon Sun- 
days -, the corps had the use of hia balloon on the other days 
of the week, until such itnie as they should have constructed one 
for themBelves. Wiihin three years they had already made 
eleven baltnon^, and gained much useful experience with regard 
to materials, varnishes, ropes, gas, etc. The ordinary gas from 
I mains waa ukbi! ; Imt for active warfare it was intended to 
' thfi Bxample of Iho French, and to generate hydrogen 
^6t by the dry nr wet way. However, it was found that the 
too lung, iLnd lasted for three or four hours ; 
f the En^littii method was adopted, and compressed 
it cylinders wuh used. Waggons were built for holding 

Fla. m. — Waggon cartying tooU utd applianccB, 
the bBlloon being packed on the top. 

(Pram " Di« OMcbichts dar LunKhlOer-AbtsUiuig.") 


twenty cylinders, each of which contained 250 cubic feet at a 
pressure of 200 atmospheres. A steam winch was made in order 
to wind up the rope holding the captive balloon ; but this was 
soon found to be a clumsy arrangement^ as steam was often not 
available at the moment when it was wanted. It was therefore 
replaced by a hand-winch, which would be always ready for work 
and could be driven by the men on the spot. Gradually the 
detachment increased. In 1886 it consisted of five officers and 
fifty men ; in 1893 there were six officers and 140 men ; and in 
1901 it formed a battalion of two companies, together with a 
team of horses. Horses are provided specially for the corps in 
order that they may be able to carry out such tactical movements 
as may be required in manoeuvres or in war. 

The corps were mainly regarded as being for the purposes 
of the Intelligence Department, and were consequently directly 
under the control of the General Staff; but in so far as uniform 
and discipline were concerned they were regarded as being part 
of the Railway Begiment. In order to distinguish them from 
the engineers of the Railway Regiment the men had the letter 
'* L " on the shoulder-straps, and also carried a rifle. Barracks 
were provided for them on the Tempelhofer Feld. 

In 1890 a military school for ballooning was started by the 
Bavarian army in Munich, and consisted of three officers and 
thirty men. They were attached to the Railway Regiment, and 
subject to the control of the engineers and the authorities of the 
fortresses. The division was afterwards made into a company. 
The non-commissioned officers and men have the letter " L '* 
on their shoulder-straps, and wear the uniform of the Railway 
Regiment, whereas the officers retain the uniforms of the regi- 
ments to which they were previously attached. A number of 
officers from other regiments also receive instruction, both of a 
theoretical and practical kind. 

The balloonists have a many-sided activity in Prussia and 
Bavaria, and are always present at the mancBUvres. They 
also take part in summer in various artillery exercises. At 
Heligoland and Kiel experiments have been carried out with 
balloons on the men-of-war. At the manoeuvres a signalling 


balloon is placed directly nuder the control of the command- 
ing officer, and haa the duty of conveying in all directions 
the orders that have been issued. The signals are conveyed 
by inflated spherical or cylindrical air-bags, which are kept 


in position in windy weather by means of a load of ballast. 
The Kaiser took much interest in the arrangements of the 
signalling balloon, and was present at the first successful trials. 

The Balloon Corps has rendered help in the matter of scientific 
investigations, particularly in the meteorological department. 
It has assisted in the exploration of the upper layers of the 
atmosphere by means of the ** Humboldt" and the "Phoenix/* 
a work which also received much encouragement from the 
Kaiser. Captain von Tschudi, one of the officers of the corps, 
superintended the preparation and inflation of the balloon 
** Prussia," which was filled with hydrogen, and had a capacity 
of nearly 800,000 cubic feet. It subsequently rose to a height 
of 84,500 ft., which is the greatest altitude yet reached. The 
battalion also takes part) in the ascents organised by inter- 
national agreement for the purpose of meteorological observa- 
tion. The expedition to the South Pole started from Kiel on 
August 11th, 1901, under Professor von Drygalski, and here 
again valuable help was given by the military authorities in the 
arrangements for the balloons, which were made from their 
designs, and have since proved of great assistance amongst the 
ice-fields of the Antarctic Ocean. 

When Marconi developed his system of wireless telegraphy 
orders were received that it was to be tested by the Balloon Corps, so 
as to find whether it was likely to be suitable for military purposes. 
This added a new field to their activities, demanding much study, 
and a great deal of experimental work. Captain von Sigsfeld was 
the moving spirit in the matter, and thanks to his efiforts, a system 
was developed which, since his untimely death, has been extended 
throughout the army. Lately this work has been removed from 
the balloon section, and has more fitly taken its place in the Tele- 
graph Department. But, for the purposes of the war in South- 
West Africa, a division was sent out that was wholly recruited 
from the balloon section, and succeeded in giving useful help. 


Experiments with captive balloons were made in England in 
1862. A military school for ballooning was started at Chatham 


in 1879 under Cnptain Templer, and in the following year the 
24th company of the Royal Engineers waB instructed in the 

H 2 


necessary field-work. MancEuvres took place at Aldershot every 
year, in wbich the ballooning section played their part ; and a 
factory with a school for ballooning was consequently erect-ed 
there. It has been already mentioned that the English were the 
first to introduce the use of hydrogen, compressed in steel 
cylinders, wbich has greatly simplified work on the field of battle. 
Military balloons, as used in England, have very light and air- 
tight envelopes. They are made out of goldbeater's skins, and 
their size ranges from 7,000 to 10,000 cubic feet. These sizes 
are much smaller than those in use in other countries, but the 

Fig. 100,— a collection of esplodeil gas cylinders, 

cost of making them is very great. The gas is mostly prepared 
by the electrolytic decomposition of water, and is stored in steel 
cylinders, 8 ft. long and 5^ ins. in diameter. In consequence of 
the low pressure, a cylinder weighing 80 lbs. only contains 
127 cubic feet of gas. In addition to this there are also the 
usual generators, which employ sulphuric acid and iron. 

England has greater experience in colonial wars than any 
other nation, and balloons have always been taken on such 
expeditions. They have thus been used in Egypt, Bechuanaland, 
and China, as well as in the Boer war. Four balloon sections 
were employed against the Boers, and the following instances of 
iheir useful servicet) may be recorded. A balloon for observation 
purposes was used in Ladysmith for twenty-nine days, and the 


positions of the Boer guns were often discovered by its means. 
Several times they were struck by shells during the siege. At 
Spion Eop it was considered, as the result of balloon observa- 
tions, that the Boer position was impregnable. A section under 
Captain Jones formed part of Lord Methuen's column, and was 
used for several days in the neighbourhood of Magersfontein, the 
balloon being finally destroyed in a storm. It was also of service 
to Lord Roberts at Paardeberg in discovering the precise position 
of Gronje's force, and in directing the fire of the guns. Another 
section was sent to Eimberley and Mafeking, and did a fortnight's 
scouting work at Fourteen Streams. Laborious marches were 
also made with inflated balloons for survey purposes. At the 
be<;inning of the war there was a great dearth of reliable maps, 
and the want was gradually supplied by means of photographs, 
taken from balloons. In places high mountain ranges had to 
be crossed, and the height to which the balloons would rise in 
such places was naturally found to be much reduced, a result of 
the physical laws which have been expounded in an earlier 
chapter. The gas was at first sent out from England to Cape- 
town, but at a later stage of the war, gas generators and 
compressors were used. 

In China the balloons were not used for discovering the 
positions of the enemy, but for the preparation of maps, and in 
this useful service the English were ably assisted by the French. 
The general experience of many colonial wars has convinced the 
English of the importance of the services which a balloon section 
can render, and in case of mobilisation the corps will be found 
to be in good working order. 


A civilian was the first to introduce the balloon to military 
circles in Austria. Some isolated experiments had doubtless 
been made, as in tlie case of Uchatius, who tried to drop bombs 
into Venice from balloons, but only succeeded in endangering 
the lives of his own comrades. Again, in 1866, a captive balloon 
was built to assist the forts round Vienna ; but on the first 



occaBion that it was taken into the field it escaped from the 
soldiers who were holding the ropes. 

In 1888, an extensive exhibition of all things relating to 
ballooning was arranged by Viktor Silberer, a well known 
amateur, who took great interest in the aporL The success of 
the exhibition was very great, and it attracted general attention 
to the subject. The inevitable committee was of course formed, 
with instructions to visit London, Paris, and Berlin in order to 
find out all that was known. 
Voluminous reports were presented 
in due course, and in 1890 a 
^^^^ military course of aeronautics was 

r^ ^S started. It was placed under the 

l^^%k L direction of Silberer, who had 

** constructed a ballooning establish- 

ment for himself in the Prater at 
Vienna. Practical instruction was 
given both with captive and free 
balloons, and the theoretical aspect 
of the matter was also considered. 
The value of the instruction was 
considered evident, and it was 
continued during the next year and 
attended by a larger number of 
men and officers. 
In 1893 a corps was organised for the special work in hand, 
and consisted of two officers, four non-commissioned officers, and 
twenty-six men, who were placed under the control of the 
arlillery stationed at Vienna. Buildings for the purpose were 
erected, and the whole organisation was placed under the com- 
mand of Captain Trieb. It was considered advisable to study 
the methods used in Prussia, and Lieutenant Hinterstoisser was 
therefore sent to Berlin lo make all necessary enquiries and to 
ac<]uaint bini^elf with the methods there adopted. He subse- 
quently took command of the coriia, and the development of its 
activity and efficiency has lately been very marked. The num- 
bers are still small; but in case of [iressing need, such as would 


arise in time of war, recourse would probably be had to the Aero 
Club, of which Silberer is president. 


The experiments made by Leppich in 1812 have already been 
mentioned ; they were entirely unsuccessful, and it was not until 
1869 that the matter was further mooted. General Todleben 
then formed a committee for the study of the military aspects of 
ballooning, the main idea being that it might probably be 
possible to introduce some improvement in the signalUng 
arrangements. The work was mostly done by the navy ; and sig- 
nalling balloons were constructed which displayed flags by daytime 
and electric lights by night. In September, 1884, a special detach- 
ment was formed, consisting of one officer (who later became 
Colonel von Eowanko) and twenty-two men. The Russians bought 
their entire outfit, including gas generators, from French manu- 
facturers, nearly all of them receiving orders in due course, viz.» 
Brisson, Yon, Godard, and Lachambre. 

It is curious to remember that the Russians ordered a dirigible 
balloon from the firm of Yon in the year 1886, but when it was 
tested, they refused to take it on the ground that it appeared to 
be useless. Experiments were also made with a Montgolfieie, 
constructed by Godard ; its capacity was 1 10,000 cubic feet, but 
the tests, which were made at Brussels, were also unsatisfactory. 
A great deal of work was done by the navy, about 1894, with 
balloons in connection with the unsuccessful attempt to discover 
the warship '^ Russalka," which had been sunk in the Gulf of 

The organisation of the corps was gradually evolved. A school 
for aeronauts was started at Wolkowo Polje, near St. Petersbuqj, 
after the French model, instruction being given both for the 
purposes of the army and navy, and extensive workshops being 
constructed. The establishment included seven officers and eighty- 
eight men, from which the detachment for the manceuvres was 
selected. They also provided any officers that were required for 
ballooning purposes. The apparatus used in the field was 


extremely inconvenient, owing to the fact that the Russians had 
not adopted the system of compressed gas in steel cylinders. 
At the manoeuvres of 1908 no less than 150 waggons were 
required by the Balloon Corps, and this had the result of inter- 
fering greatly with the movements of the troops. Consequently 
General Dragomiroff expressed himself as being very dissatisfied 
with their arrangements. But the outbreak of the war with 
Japan changed the system ; the spherical balloon was given up, 
and a number of kite-balloons were ordered in Germany. The 
method of generating hydrogen from sulphuric acid and iron 
was abandoned. It was considered necessary that everything 
should be capable of transport either on mules or in two- wheeled 
carts, and the gas was therefore generated by the reaction 
between aluminium and caustic soda, all the materials required 
to inflate one balloon being carried on twenty mules. A battalion 
of the East Siberian Balloon Corps was formed for the campaign, 
consisting of two companies, which reached the front in 
September, 1904, and another company was already with the 
first army under Linevitch. The reports which have been made 
public as to the results of the campaign from the point of view 
of ballooning experience are very meagre. Reconnoitring work 
of various kinds was often done under the heavy fire of the 
Japanese, and to judge from the number of decorations that 
were afterwards bestowed it would appear that the second com- 
pany must in some special way have distinguished itself. The 
balloon which had been intended to be used in the forts of Port 
Arthur was loaded on board a ship and subsequently captured ; 
and the same fate probably overtook a German steamer, named 
Lahn, which was intended to help in the service, but disappeared 
mysteriously. At the present moment Russia is devoting herself 
to the reorganisation of the service in the light of the experience 
gained from the war. It may also be mentioned that kites have 
been used, principally in the navy, for purposes of observation ; 
but the results have not been altogether encouraging. Reference 
will be further made to the matter in a later chapter. 



The balloon disappeared from the army of the United States 
for thirty years until a fresh effort was made in 1892. The 
material then employed was goldbeater's skin, and a balloon of 
this kind, together with net and basket, was shown at the 
Exhibition at Chicago. In the following year English methods 
were adopted, and storage accommodation was supplied at Fort 
Logan. Experiments were also carried out by Lieutenant Wise 
on the use of kites, which have been already described. 

In the war against Spain, Major Maxfield with his company 
did good work in the field. At Santiago de Cuba the observa- 
tions which were made of the arrangements of the forts were of 
great value, and it was also similarly known that Admiral 
Cervera's fleet was in the harbour. Later in the campaign the 
Spaniards succeeded in chasing the balloon through the dense 
brushwood with their cavalry, and in bringing it to earth with 
some well directed rifle fire. This was merely the result of a 
lack of caution, and helps to emphasise the fairly obvious fact 
that the balloonist must be on his guard against surprises of this 
kind. It is insufficient for him to direct his telescope towards the 
horizon, more especially as it is also a part of his duty to report to 
the commanding officer as to the movement of any of his own 
troops which may no longer be in touch with headquarters. 

After 1890 a disposition was shown to imitate German models 
in America. Gradually the organisation was completed both 
for the employment of balloons in forts and in the field. Most 
countries started by copying French methods, but lately there 
has been a decided tendency to follow German practice. The 
following notes give brief particulars of the various countries in 
alphabetical order. 

In Belgium the necessary materials were ordered from 


Lachambre, of Paris, in 1886, and a company of an engineering 
regiment in Antwerp was allotted for ballooning work. A schodl 
was started in the following year, and trials were made of hot 
air balloons on the Godard system, as well as of others for 
signalling purposes of the dirigible type. Lately the kite-balloon 
has been introduced. 

During the exhibition in Philippopolis a small company was 
organised by Eugene Godard in Bulgaria; but it can hardly be 
said to have resulted in any real military organisation. 

China claims for itself the credit of having invented 
Montgolfieres centuries before Montgolfier was born ; but it has 
since somewhat failed to keep in the van of modern progress. 
It must, however, be admitted that in 1886 Yon, of Paris, was 
instructed to deliver two balloons, with all [necessary appurte- 
nances, in Tientsin, and several months were spent in inducing 
them to rise in the air. This delay was caused by the fact that 
the varnished silk melted into a slimy mess on account of the 
tropical heat. Meanwhile suitable storage accommodation was 
provided, together with a ground from which the ascents could 
be made, and the various exercises carrried out. Naturally 
enough the plans included the erection of a magnificent pagoda, 
from which the presiding viceroy could conveniently follow the 
manoeuvres. After all the preparations had been completed, it 
was found that the balloons were completely useless, and more 
were therefore ordered with all haste from the same contractors. 
These arrived in time to fall into the hands of the Russians at 
the capture of Tientsin in 1900, and nothing further is known 
about the state of the art in China. 

Unsuccessful experiments were made in Denmark between 
1807 and 1811 with a dirigible balloon ; but it was not till 1886 
that an officer was sent to Belgium, England, and France, to 
study the question. This journey resulted in the giving of an 
order to Yon, of Paris, for a complete equipment for one balloon. 
When this arrived it served for various exercises till it was 
eventually worn out. Nothing further has been done in the 

In 1885 a complete ballooning outfit was ordered by the 


Italian Government from Yon, of Paris, and a company was 
formed, which has done mnch work in the field. English 
methods were, however, followed in 1887, goldbeater's skin being 
UBed as a material, and steel cylinders being introduced for 
oompresaed gas. At the same time French methods were not 
entirely discarded ; silk balloons and gas generators were 
employed to some extent. A company was sent to the front at 

i'lG. 102.— After a lauding. 

the time of the war in Abyssinia, the balloons being transported 
on mules and camels. The German kite-balloon was employed 
in the navy in 1900, and in 1901 the system was still more widely 

A legend is still told of a Japanese soldier who mounted in a 
kite during the siege of a fortress in 1869, and threw bombs on 
the heads of the enemy. This may be true, but it has a slightly 
mythical sound, not altogether out of keeping with the air of 
mystery which veiled Japan at that time from the gaze of the 
outer world. The first fact which is definitely known about 


Japanese ballooning activity in its military aspect is that the 
firm Yon, of Paris, supplied them with the necessary materials 
in 1890, though it was supposed at the time that the 
Germans might have received the order owing to the known 
partiality of Prince Eomatzu for their products. However, the 
Japanese had the same experience as the Chinese, and found the 
varnished silk balloons useless for their purpose. Many 
enquiries and experiments were therefore made with a view to 
finding suitable material, varnishes, etc., and finally a kite-balloon 
was ordered from the firm of Riedinger, in Augsburg. Experiments 
were still being made at the time of the outbreak of the war 
against the Russians, and balloons and kites of all shapes and 
sizes were soon to be seen on the field of battle. In particular 
they did good work in directing the fire of the Japanese guns at 
Port Arthur, so that several Russian magazines were exploded 
by the shells. 

Morocco ordered balloons from Surcouf, of Paris, in 1902, and 
at the same time a steam- winch for captive balloons was delivered 
by Schneider, of Creusot. 

The Netherlands procured their supply from Lachambre in 
1886, and this was handed over to a regiment of engineers 
stationed at Utrecht. A company was also formed in Batavia, 
and the German kite-balloon was introduced in 1902. Norway 
has a corps provided with German material. In 1893 Godard 
instructed some Roumanian officers in the art of ballooning, and 
an order was afterwards given to the firm for the supply of 
balloons to a regiment of engineers stationed at Bucharest. In 
1902 an officer was sent to Germany and Austria to study their 
methods, and this led to the introduction of the " Sigsfeld- 
Parseval " system of captive balloons into the Roumanian 

Sweden had a similar experience to that of Roumania and the 
Netherlands. In 1897 a corps was formed in the fortress of 
Vaxholm, and material was supplied by the firms of Godard and 
Surcouf, in Paris. In 1900 an officer was sent to Versailles to 
study the French methods of instruction. A year later Lieutenant 
Saloman was sent to Vienna for a similar purpose, and in 1905 


Lioutenant von Rosen waa attAched for several months to the 
corps stationed at Berlin. A balloon-ship was introduced in the 
Swedish Navj in 1903, intended for purposes of coast defence. 
It carried a German kite-balloon of a capacity of 25,000 cubic 
feet, which is filled with hydrogen, produced electrolytically, and 
compressed in cylinders. 

In Switzerland a corps was formed and stationed at Berne. 
It was originally fitted out with French supplies, but in 1901 

103. — A balloon ready for ioflation. 

orders were given in Germany for further requirements. Servia 
has used balloons since 1888 for signalling purposes, and has 
lately proposed to introduce them for reconnoitring work. 

Spain has also been very actively engaged on the work. In 
1884 it was proposed to furnish their own supplies, but five 
years later orders were given to Yon, both for balloons and 
generators. On June 27th, 1889, the first and only Royal 
ascent that has ever been made took place, when Queen Marie 
Christina mounted the car in Madrid. Lately officers have been 
sent to all parts of Europe to study the latest improvements^ 


and in 1900 the kite-balloon, dae to Sigsfeld and Parseval, was 
introduced into the corps, which was stationed at Guadalajara. 
It is now under the command of Colonel Vives y Viches, who 
has furthered the development of its efl&ciency in many directions. 
His interest in scientific work was shown by the assistance he 
afforded to the meteorologists and astronomers on the occasion 
of the last eclipse of the sun, and he has also encouraged his 
men to do photographic work and train carrier pigeons. 

It will therefore be seen that almost every civilised nation is 
developing its ballooning capacities, and lately there has been a 
tendency towards the adoption of German models, evidence of 
which is to be found in the fact that within the last nine years 
the firm of Riedinger, in Augsburg, has supplied more than 500 
spherical and kite-balloons. 



Balloons can be filled either with hydrogen, water gas, or 
coal gas. The preparation of hydrogen can be effected in various 
ways. The method originally suggested by Charles is probably 
the simplest, and consists in the addition of dilute sulphuric 
acid to iron. But practically it leads to difficulties. The newly- 
generated gas is very hot, and adulterated with a certain amount 
of acid vapours. It must therefore be cooled and washed free 
from impurities. This is done by allowing it to pass through 
flowing water, after which it is dried by coming into contact 
with substances which easily absorb moisture, such as calcium 
chloride. It is then ready to be passed into the balloon. This 
method is still employed with various modifications ; iron can, of 
of course, be replaced by zinc, and sulphuric by hydrochloric acid. 

The chemical formula showing the reaction is as follows, viz. : 

HaSOi + Fe = Ha + FeSOi, 

i.e., the addition of sulphuric acid to iron forms hydrogen and 
ferrous sulphate. From this formula it is possible to calculate 
the amount of gas that is formed. The atomic weights are 
H = 1, S = 82, = 16, Fe = 56. A cubic foot of hydrogen 
weighs 0*09 oz. Suppose it is required to know how much iron 
and sulphuric acid will be needed to generate sufficient hydrogen 
to fill a balloon of 20,000 cubic feet capacity. We find, first of 
all, the weight of the hydrogen, which is 20,000 X 0*09 oz., 
i.e.f 1 cwt. The amount of iron will be 28 times the weight of 
the hydrogen, and will therefore amount to 1 ton 8 cwt. ; the 
weight of sulphuric acid will be 49 times that of the hydrogen, 
and is consequently 2 tons 9 cwt. In the process of the work 
losses of one kind or another are sure to arise, added to which the 
iron will probably be rusty, and the sulphuric acid will certainly 



contain impurities. It will therefore be found that in'actual 
working about '20 per cent, more sulphuric acid and iron will be 
required than is allowed for in the calealationB. 

If hydrogen is generated on this Bjetem it starts very fast, 
but gradually the evolution of the gas becomes slower, until it 
finally ceases altogether, owing to the formation of a film of 

td CapUin Spei 

ferrous sulphate on the surface of the iron. The so-called 
circulation system was therefore introduced as an improve- 
ment, by which the fluids are kept in a state of circulation, 
and the iron sulphate is steadily removed in consequence. 
It is very important to use pure sulphuric acid, because the 
cheaper kinds contain arsenic. The use of impure acid has led 
to several fatal accidents, and the smallest amount of arsenic 



produces Buoh an effect on the red corpuscles in the blood that 
death quickly results. The vats or barrels must be lined with 
lead, which is the only common metal not attacked by sulphuric 
acid. If suitable arrangements are made, it is possible to gener- 
ate a large quantity of gas in a very short space of time. In 
1676, Henry Giffard prepared nearly 900,000 cubic feet of gas in 


three days, using in the process 180 tons of sulphuric acid and 
80 tons of iron turnings. 

It has been already mentioned that the first military use of 
the balloon took place soon after the French lievolution, and 
that one of the conditions was that sulphuric acid was not to be 
used for the generation of the hydrogen, seeing that all available 
sulphur was required for making gunpowder. Coutelle therefore 
devised an arrangement by which Lavoisier's method of passing 


Bteam over red-hot iron was used for the generation of hydrogen. 
Some iron retorts (old cannons were actually used) were built 
into a furnace and kept at a red heat. They were then filled 
with iron turnings, and steam was turned on. Hydrogen was 
therefore generated, as shown by the following formula — 

Fes + 4 H2O = Fe^Oi + Ha. 

If this method is used, a cubic foot of hydrogen will require 
1*881 oz. of iron, and 0*806 oz. of water. Improvements were 
also made in this arrangement, but the main principle remained 

the same. 

The purest gas is obtained from the electrolytic decomposition 
of water. A little sulphuric acid is added to the water in order 
to make it conduct. On passing an electric current, the water is 
decomposed into its constituents, which are hydrogen and oxygen, 
the hydrogen going to the negative and the oxygen to the positive 
pole. In Germany the ordinary way is to produce hydrogen as 
a bye-product in the soda works, as, for instance, at Bitterfeld, 
near Halle, and Griesheim, near Frankfort. The cost of carriage 
is considerable, so that it is worth 14«. per 1,000 cubic feet, 
whereas at the works it might be. had almost for the asking. 
The cost of the gas, if prepared from sulphuric acid and iron, 
would probably be nearly twice as much. 

Water-gas is obtained by passing steam over red-hot carbon, 
and consists of a mixture of hydrogen and carbon monoxide. 

A large number of other reactions can be used to generate 
hydrogen, but they are either dangerous or costly or cumbrous. 
Amongst these may be mentioned the reaction between slaked 
lime and zinc, between steam and fused zinc, between sodium 
and water, or potassium and water, and between zinc or aluminium 
and either of the caustic alkalis. 

In any case the generation of the gas on the field of battle 
would be out of the question, and the English method of using 
the compressed gas in steel cylinders is now everywhere employed. 
A cylinder with walls 0*187 in. thick weighs about 88 U)S. and con- 
tains 140 cubic feet under a pressure of 120 or 130 atmospheres. 
A military waggon carries 85 cylinders, and the gas is allowed to 


pass into the ballooa by opening tlie valve at the top of the 
cylinder. When a balloon ia to be inflated, several waggons are 
drawn up at the Bide, and the various cylinders are all connected 
to a tube, which conveys the gas to the interior of the balloon. 
The inflation occupies from 15 to 20 minutes. 

I'iG. lOe.^Steel cylinder lor containing; hydrogen. 

Coal gas is only used for free balloons, and was first proposed 
by Green in 1818. The " lift " due to the use of the hydrogen 
or coal gas has been already studied in an earlier chapter, and it 
was there shown that the size of the balloon depends on the 
amount of lift that is wanted. Therefore cap- 
tive balloons, which are generally filled with 
hydrogen, are much smaller than free balloons 
filled with coal gas. If it were not for the 
matter of expense the use of coal gas would 
certainly be discontinued. 

The sphere ia the body which combines the 
smallest surface with the greatest volume, and 
therefore all free balloons are spherical in 
shape. The size is obviously dependent on the 
weightof the load to be lifted. Generally speak- 
ing,a balloon to carry S or 4 persons would have j.j i^j _9ecHon 
a capacity of 45,000 cubic feet or thereabouts, through bi«1 

The bigher the balloon is to rise, the greater cylinder, 

must be its capacity, and, of course, with hydrogen, much 
greater heights can be reached than with coal gas. If long 
journeys are to be undertaken, large balloons are necessary. 
This arises from the fact that leakage is continually occurring, 
and it must be possible to neutralise this by throwing out ballast. 
In other words, the balloon must be capable of carrying a con- 
siderable load of ballast, and must therefore have a large capacity. 
The materials used for the construction of the envelope are very 

N 2 


numerous. Dirigible balloons may have a framework of alu- 
minium sheets, but it is better to use some kind of woven 
material. Paper and rubber are only used for pilot balloons; 
they are also useful for meteorological purposes, and are sent to 
great heights in the manner suggested by Assmann. But they 
have very small power of resistance, and have generally done 
their work after making one ascent. The Italian balloonist, 
da Schio, put a rubber band inside the envelope, for purposes 
that have been already explained. 

Goldbeater's skin, which is so called owing to its having been 
used for beating gold into thin sheets, is used in England for 
making the envelopes of balloons. These skins are about 
86 inches by 10 inches ; they are very light and hold the gas 
well without needing to be specially varnished. They are laid 
in layers, one upon the other, sometimes as many as eight being 
used. Twenty-five square feet of the skin weigh about 1 ounce, 
and would probably be used in layers of five. Unfortunately 
they are extremely expensive, and not very suitable for continu- 
ous exposure to the weather. There is, however, an advantage 
in using balloons of this type in colonial wars, partly because 
they are very light, and partly because the tendency to develop 
leaks is slight. Seeing that under such conditions the genera- 
tion of gas, to make good any leakage, would be a difl&cult 
matter, it will be evident that this advantage is worth 
paying for. 

Of woven materials, the most important are silk and cotton. 
Linen is sometimes used in forts in time of war, but seldom 
otherwise. Silk is both light and strong, but also expensive, 
and little capable of resisting the weather. Vegetable sub- 
stances withstand atmospheric influences better than those of 
animal origin. In France, the military balloons are made of 
the so-called "ponghee" silk, which is of an inferior quality, 
and therefore cheaper. One layer is suflScient on account of the 
great strength of the material. When cambric is used, it is 
necessary to have two layers, which are placed diagonally, one 
on top of the other, so that the pattern of the one is at an angle 
of 45 degrees to that of the other. This much increases the 



strength of the covering. It is necessary that it should be very 
closely woven throughout, and that it should be in all places of 
the same strength, special machines having been designed for 
testing its resisting power. All envelopes made of silk or cotton 
require to be varniehed in some way. The oldest method was to 
coat it with rubber solution, as proposed by Charles, applied by 
hot rollers. This is also vulcanised with sulphur, which helps 
to preserve it. However, light has the effect of gradually dis- 
integrating lubber, and this can to some extent be prevented by 

FIO. 108.— Making balloon ei 


colouring ib with a yellow paint. A better plan is to varnish the 
envelope with linseed oil, though it must be admitted that it 
has the unpleasant property of becoming very sticky in hot 
weather. Great care must be taken in storing such balloons, as 
they are very liable to catch fire spontaneously. The methods 
that were employed in making the old varnishes are unfortunately 
no longer known. Several other things have also been used for 
making the coverings airtight ; but nothing better is known than 
linseed oil varnish, or rubber solution. One square foot of 
" ponghee " silk, as used for French military balloons, with 
five coats of varnish weighs 1'2 ounces, and one square foot of 



double thickness of cambric with five coatings of rubber solution 
weighs about one ounce. At any part of the covering where the 
wear and tear is likely to be specially great it must be stiffened 
by an extra layer ; this is particularly the case at the parts in 
the neighbourKood of the valve. The spherical covering is 
made by sewing together a number of pieces of the material, 
the breadth of these pieces depending on the width in which 
the material is delivered. It varies generally from 20 to 65 
inches, and about 2 inches must be allowed for the seams. The 
number of widths of material that will be needed can be found 
by dividing the knpwn circumference by the width of the stuff. 
There will be a certain amount of tapering at the top and 
bottom, and instead of tedious calculations, this is usually 

adjusted by some sort of pattern, the 
bottom being of course exactly the 
same as the top. There are many 
different ways of working to patterns, 
and Professor Finsterwalder of 
Munich has proposed several new 
methods, by which a saving of 80 per 
cent, of material can be obtained. 
He inscribes a cube in the sphere, and produces its surfaces till 
they intersect the surface of the sphere. In this way, six square 
pieces are formed with twelve dividing lines, three of which meet 
at a corner. It is easy to see from the diagram how the pieces are 
put together. The seams are covered with strips, both on the 
inside and outside, which are made to adhere with rubber solution. 
At the bottom of the envelope the tubular opening, used for 
inflation, is secured to a wooden ring. It is generally left 
unclosed, so that, as the balloon rises, the gas can freely 
escape. A Frenchman, named Mallet, devised an arrangement 
by which air is prevented from being sucked into the balloon, 
and used it on one of his expeditions with success. He remained 
in the air for 36J hours, and covered a distance of 560 miles. 
The neck is joined to the ring by ropes ; by cutting away these 
ropes the balloon will fall like a parachute, in case it should lose 
its gas. 

Fig. 109. — Professor Finster- 
walder*8 patterns for balloon 


At the top of the balbon iB placed the valve, which is either in 
the form of a disc or of the butterfly type. Strong springs are 
used to close it after it has been opened for any purpose, and the 
valve ie made tight by preBsing ite sharp edge against a rubber 
seating. It was 
the general cus- 
tom, years ago, to 
litte the valve 
with some kind of 
cement to make it 
fit tighter ; but 
this plan was 
given up, as it 
was found that the 
valve no longer 
fitted tightly after 
it had been once 
opened. The valve 
is opened by a 
cord, which passes 
through the infla- 
tion tube to the 
top of the balloon. 

On the covering 
there is a strip, 
which begins at a 
distance of 20 ins. 
from the valve, 
and extends half 
the way down, 
gradually broad- 
ening towards the 
bottom ; it is covered by a similar strip on the inside, the two 
being cemented to the envelope, but not sewn. At the moment 
of reaching the ground, this strip is ripped off by means of 
a cord, and helps the balloon to empty suddenly. The danger 
of bumping along the ground is in this way generally avoided. 

Fig, nil.— Uallooi 


In Germany, the ripping-cord is always used, because it ensures 
a safer landing. A clever aeronaut with a little practice and with 
the use of the ripping-cord can alight with certainty where he 
chooses, even in a strong wind ; and this is a matter of great 
importance, particularly in order to avoid damage to growing 
crops. Gusty winds often make the landing a matter of difficulty ; 
but in this way it is possible to descend suddenly on any con- 
venient spot that may present itself. As a matter of history, it 
may be stated that the first man who was called upon to pay 
damages was Testu-Brissy in 1786. Of course the greater part 
of the damage was done by the rustics who flocked to see what 
was going on, as, indeed, always happens ; but Testu-Brissy was 
expected to make good all the havoc that had been wrought by 
their ill-timed zeal. 

In other countries the ripping-cord is only used in cases of 
emergency. The French sew the " corde de la misericorde " 
tightly down, so that it can only be pulled with a very vigoorus 
tug. The ripping-cord was the invention of the American 
aeronaut. Wise, in 1844 ; Godard introduced it into France in 
1855. The present form in which it is used in Germany was 
devised by Major Gross. A safety-catch prevents it from being 
used unintentionally. It has indeed happened that the wetness 
of the ropes has caused it to act, but luckily nobody is known to 
have been killed by such an accident, though a sudden fall from 
a great height may easily cause a most serious accident. It has 
also happened that at the moment of reaching the ground the 
wind has blown the balloon over, so that the opened seam was 
downwards ; the consequence was that a long series of bumps 
and jolts followed before the balloon came to rest. This can, 
however, generally be prevented by the guide-rope. The ripping- 
panel is placed on that side of the covering to which the guide- 
rope is attached. The friction caused by the trailing of the rope 
will cause this side of the balloon to be at the back, and any shock 
caused by the bumping of the car against the ground will drive it 
upwards and give the gas a clear passage for escape. The guide- 
rope was first introduced by Green in 1820, in order to lessen the 
shock caused by the bumj)ing of the oar at the moment of landing. 



In order to protect the envelope and to distribnte the load 
equally to all its parts, it is covered with a net which is secured 
to the valve, and serves also to support the basket. The ring of 
the balloon is either 
made of steel or of 
several thicknesses 
of wood ; the ropes 
for supporting the 
basket are secured 
to it, as well as the 
guide-rope and the 
holding-ropes. The 
ring itself is hung 
from the network, 
and the basket is 
hung by a number 
of strong ropes from 

the ring. It carries the passengers, together with such instru- 
ments and ballast as are necessary. It is from 2 ft. 6 in. to 
4 ft. deep, and the area of floor space is usually about 4 ft. by 
6 ft., though this of course 
depends on the number of 
passengers it is intended to 
accommodate. Itisproposed 
by the International Balloon 
Association to fix the size of 
cars, so that they can always 
be easily carried on any 
luggage train. 

The basket is made of 
rattan and osier work, the 
whole thing being, as it were, 
woven together. The supporting ropes pass t)irough the bottom 
and are woven in with it. Buffers are fitted on the outside to 
take up the shocks. It is generally padded on the inside so 
as to prevent damage to the passengers in case of heavy 
bumping. Baskets are provided in the place of seats, and are 

). 111. — The Gret ripping-panel used in a balloon 

■eli'jie M ipping -panel. 

[O. 112. — arrangements for ripping- 
(From Moedebecka '-Focketbook. ") 



used to hold the instruments, provisions, etc. Aeronauts who 
object to the use of the ripping-panel always take a grappling 
iron, which is intended to help the landmg operations, but it is 
of course practically useless if the ground is rocky or frozen. The 
designs for grapnels are very numerous ; all, doubtless, are 
made with the intention of improving the grip under unfavour- 
able conditions. The shocks which a balloon 
sustains from bumping on a windy day are 
only made worse if the grapnel succeeds, 
every here and there, in getting a momentary 
hold. It throws a very serious strain on all 

Fig. 113.— Net of a 

(From Mowle beck's 
" Pocketbook.") 

Fig. 114.— Different kinds of grapnel. 
(From Moedebeck's "Pocketbook.") 

parts of the construction, and would appear to offer no advantages 
as compared with the use of the ripping-cord. Ballast is kept 
in strong bags of sail-cloth, from 12 to 15 in. high, and 8 to 
12 in. in diameter; they are suspended by four ropes from 
a hook. A large piece of sail-cloth is used to protect the balloon 
after it has been rolled up and is ready for packing ; this is tied 
on the outside of the balloon during the jom-ney ready for use. 


The Captive Balloon. 

A captive balloon is very much at ihe mercy of the wind. If 
the breeze happens to he strong it will be blown hither and 
thither, and may indeed be pitched heavily on the ground. 
With a free balloon there is a feeling of perfect restfulness, and 
no symptom either of sea-sickness or giddiness. One glides 
peacefully along, and even the most giddily -in dined person feels 
no sensation of discomfort. It is entirely different with a 
captive balloon, with its incessant rolling and vibration; the 
discomfort is often 
very great. This 
naturally interferes 
with any observa- 
tions, and the use of 
a telescope is often 
quite impossible. 
The height to which 
it can ascend is 
limited, and a cap- 
tive balloon can 
scarcely be used in 
a wind exceeding 
26 ft. per second. 
All sorts of attempts have been made to improve this state of 
things, mainly by special systems of suspending the basket. 
But nothing has really been effected by these methods. The 
real improvement has come through the invention of the kite- 
balloon by Captain von Sigsfeld and Major von Parseval, and 
this allows the use of a captive balloon in a wind blowing at 
66 ft. per second. 

The main idea embodied in the kite-balloon consists in using 
a longish balloon, that sets itself diagonally, like a kite, to the 
direction of the wind, Archibald Douglas proposed it about 1845, 
but the balloons that were then constructed were not successful. 
The kite-balloon is manufactured by the firm of Riedinger in 
Augsburg ; it is now in use in most countries, and has proved 


Buccessfal even under trying conditionB. It possesaes the great 
advantage of having no rigid parts in its construction, with the 
single exception of the valve. 
The envelope consists of a 
cylindrical portion about 50 ft. 
long, with hemispherical ends, 
having a radius of 10 ft. The 
shape is preserved by the use 
of an air-bag, with a capacity of 
5,300 cubic feet ; an ingenious 
arrangement is used by which 
it is automatically filled hy the 
wind under pressure. Sup- 
pose the balloon to be slightly 
inclined to the horizontal, and 
that a section is made on a 
horizontal plane passing 
through the middle of the 
lower hemiephetical end. The 
air-bag is then fastened to the 
body of the balloon round the 
edge of this sectional plane. 
It is therefore joined to both 
the hemispherical and cylin- 
drical portions, and forms a 
sort of inner envelope, leaving, 
however, a space between the 
two, into which the air can be 
driven by the wind. In this 
state the balloon must be sup- 
posed to be fully inflated. As 
soon as it rises, the gas 
expands, and the pressure on 
the envelope would increase to 
the bursting point if the gas 
were not allowed to escape. The valve is however opened by 
a cord as soon as the air-bag is completely emptied. The careful 

Fig. lliiA. — The kite-balloun disigaed 
b; Major von I'lusoval and Major 
von SigsM.!. 



adjustment of this rope is therefore a matter of great importance. 
As soon as the volume of the balloon begins to contract, air enters 
through an opening into the air-bag, and the valve closes of its 
own accord. A non-return valve prevents the air from escaping, 
and the capacity of the air-bag is about 5,300 cubic feet, when it 
is completely filled. 
The air is slightly 
compressed by the 
action of the gusts 
of wind, and this 
pressure extends to 
the hydrogen and 
reacts upon the 
envelope. This is 
resisted by an in- 
ternal pressure equal 
to that on the out- 
side, and also by the 
static pressure acting 
on the top of the 
balloon, which, ac- 
cording to Parseval's 
reckonings, amounts 
to the pressure of a 
Fig, lie— Drawing ehowing the design of the column of water, O'S 

or 0-4 in. high. If 
there is a suf&ciency 
of gas the envelope 
must always retain 
"' ■""'"* '"•'■ its shape. As soon 

as the pressure increases owing to the rising of the balloon, the 
air is pressed out of the air-bag into a " steering-bag " through a 
connecting valve. The wind therefore automatically fills up 
any deficiency which may arise. 

The balloon assumes an inclined position at an angle of about 
80° or 40* to the horizontal ; this is efl'ected through the method 
by which the ropes are attached. It is held captive by a rope 

emptying I 
Naht des D 

KctM = belt. 
iMlIoon or jta CO 
« HtiiHIliK boi. 

Df S^.tlBI 



which is not attached to the basket, but to the front and back 
of the balloon. These ropes are so arranged as to prevent the 
long body of the envelope from being bent, and it is very impor- 
tant that the longer axis of the balloon should be kept pointing 
in the direction of the wind. This is effected by means of a 
steering-bag, which is connected to the lower part of the cylin- 
drical and hemispherical portions of the balloon. The wind is 
driven into the steering-bag through one or more non-return 
valves, and escapes again through an opening at the back 
towards the top. There is therefore a slight excess of pressure 

KiG. 117. — Basket suspension. 

in the steering-bag, but it must always be less than that in 
the air-bag itself, which discharges into it. The result of the 
excess of pressure in the steering-bag is that the balloon 
always follows the direction of the wind. But in order that 
these movements should not take place too suddenly, a kite's 
tail is tacked on behind, and secured to the main body of the 
balloon by means of a rope on either side. The kite's tail 
consists of a number of windbags, which look like inverted 
umbrellas, blown up by the wind, and therefore tending to 
check any movement. But this arrangement has the draw- 
back that the balloon is somewhat dragged down, and a 
portion of the kite-effect is lost. This is, however, neutralised 


by the use of two sails, which are mounted at the sides of 
the body, and contribute also to an increase of stability. 

The balloon has no actual net. Instead of this there is a 
strong belt, which passes round the sides at a depth of 10 ins. 
below the middle line, and parallel to the longer axis. It is 
fastened securely to the envelope by stitching, and by cementing 
it to the body with bands coated with rubber solution. Eopes 
are attached at various points to the girdle, but they might 
happen in very windy weather to be broken. A ripping-panel 
is therefore provided at the front, in order to bring it quickly 
to the ground. Experience shows that a free kite-balloon 
maintains its position with very little change, if held by a 
rope attached to the front, though in this case it is generally 
inclined at a greater angle to the horizontal. 



The most important; inBtriiment is the barometer, which is 
used for determining the altitude. The balloonist must know 
the height to which be has risen, and also notice any tendency 
to riee or fall as soon as possible. There is a certain sluggish- 
ness about aneroids, which can be corrected by gentle tapping. 
The method, which has been described, of throwing out pieces 
of paper or feathers forms a 
useful indication of a rise or 
fall, and may conveniently sup- 
plement the use of the baro- 

On an ascent in a free balloon, 
a barograph is always taken, 
which records the barometric 
reading on a roll of paper, and 
therefore, together with the 
notebook, forms a concise 
statement of the facts of the 
journey. The statoscope has 

FiB.llS.-AneroidUroaieter. ^j^^ ^^^^^ described, and IB by 

no means indispensable, but a compass must be taken in any case. 
For meteorological observations, a wet and dry bulb thermo- 
meter, preferably of the Assmann type, should be taken, in 
order to measure the temperature and the moisture in the 
atmosphere. Radiation is, however, more important than actual 
temperature. The gas inside the balloon is warmer than the 
surrounding atmosphere, except by night, when the temperatures 
of the two are nearly the same, the gas being sometimes slightly 
the colder of the two, owing to losses by radiation. 
It is very ueceHsary to take good maps of the district. But on 


a long journey, they are apt to be bo numerous that they are now 
often replaced by maps on a very small scale, which are read 
by means of a magnifying glass. As this system is possibly a 
matter of some general interest for other purposes than balloon- 
ing, it may be as well to describe it a little more fully. The 
method is due to an officer of the Bavarian Balloon Corps, named 
von Weinbacb, who communicated his ideas to Dr Vollbehr 
of Halensee. An instrument, called the microphotoscope, was 
therefore designed. It consists of two parts, which are quite 
separate from one another, viz., the eyepiece or magnifier, which 
is used in daylight, and a lighting device, which ts used by night. 
The magnifier consists of a lens, which is so mounted as to 

Fio. 119. — Barograph, or recordiog barometer. 

be capable of moving in slots, either up and down, or to the right 
and left. Mierophotographs, which represent photographic 
reductions of maps published on a larger scale, are taken on 
celluloid films, and mounted in position between thin sheets of 
glass, two inches square. The lighting arrangement contains a 
small electric glow-lamp and a battery, the lamp being switched 
on and off as required. This arrangement works well on night 
journeys, and it ia generally possible to determine the locality 
by noting the lights in the towns and the positions of the 
railways. The daylight apparatus weighs 4 oz., the lighting 
apparatus 6 oz., and the complete thing together with the ease 
weighs 13 oz. The price is twenty-five shillings, which may 
easily be saved in the cost of maps. 

It is extremely necessary to see that the whole of the material 
is maintained in thoroughly sound condition. Everything must 



be carefully examined before starting. With a free balloon, this 
is particularly neceBsary, seeing that damage may have been done 
at landing or by the ripping-cord. It is always emptied after a 

Fro. 120.— Balloon basket and 

jourQey ; the gas soon becomes adulterated by diffusion, and it'is 
not generally possible to anchor an inflated balloon. Sometimes 
a balloon can be loaded with ballast and left in its inflated con- 

Fig. 121. — VoUbchr'a microph otoscope for reading maps on a reduced 
senle, togetber with illuminating device for night work. 

dition during the night, if the weather 18 very fine ; then on the 
next day it is possible to continue the journey with a smaller 
number of passengers than before. Things are somewhat 
different with a captive balloon, which is often left in the inflated 



state for several days, in order to save eipense ; when at last it 
no longer has sufficient lift, it is emptied and refilled. L^baady's 
motor-ballooD worked for several months with one filling of gas. 
When it is emptied, the gas is simply passed into the air, and ia 
osetess for apy further purpose. In Germany, a balloon is emptied 
by means of the ripping-cord ; in other countries, a asual method 

Flo. 122. — Microphotoscope 

is to open the valve, or to raise the mouth of the neck. The 
kite-balloon is emptied through a special opening towards the 
back at the top. The ripping-panel must of course be veryloare- 
fully cemented down after use, and this ought to be done not 
more than three days and not less than one day before making 
a fresh start. If it is left for a longer time, it often sticks so fast 

Fig. 123. — Microphotoscope, with magnifying gli 

in day light. 

that it requires the efforts of several persons to pull it apart 
again, and in rough weather this may easily cause a great deal 
of unpleasant bumping. The opposite happens if the patch'is 
closed too soon before starting, or if the benzine contained in the 
rubber solution is not allowed to evaporate sufficiently before 
putting the piece in position on the covering. 
The examination of the envelope on the inside is carried out 


by several persons, after it has been filled with air. The most 
minute leaks can easily be detected; the light which passes 
through them draws attention to their existence, even though it 
is impossible to see any trace of a hole on the outside. All such 
holes must be patched both on the outside and inside. Rents 
are first sewn together and then patched, and any kind of injury 
must be made good by covering with fresh material. 

With kite-balloons it is necessary to see to the adjustment of 
the valve ropes. The balloon must therefore be filled with air, 
and if the valve does not open properly when the envelope is full, 
the connecting cord must be shortened. Everything in fact must 
be carefully overhauled before a start is made. Great care is 
necessary if accidents are to be avoided, and even though it is 
impossible to avoid them altogether, it is none the less a fact that 
the danger in ballooning is no greater than in driving a motor 
car or sailing a yacht. 



Professional aeronauts made their appearance soon after the 
mvention of Montgolfieres. Blanchard, Robertson, and others 
soon found that it was possible to make a little money out 
of the new discoveries, and it can be easily understood that 
the tricks of the showman's art soon brought the sport into 

A balloon, made out of goldbeater's skin, was sent up on 
December 27th, 1788, without passengers, from the Lustgarten 
in Berlin by Professor Achard. In 1789, Blanchard made one 
of his ascents; but the first properly managed expedition 
with passengers was made in Berlin on April 18th, 1808, by 
Garnerin, who was accompanied by his wife and a man named 
Gartner. A full description of this journey has lately been 
published from documents in the possession of one of Gartner's 
descendants. It appears that the ascent was made in the presence 
of the King and Queen of Prussia and an immense concourse of 
people. The start took place in the garden of the Veterinary 
School in Berlin, and the balloon eventually came to the ground 
near Mittenwald in the forest of Wusterhausen. 

Nothing further was done with regard to the sport of ballooning 
in Berlin till 1881, when the German Club for the Promotion of 
Ballooning was founded by Dr. Angerstein. The search for a 
dirigible balloon appeared at that time to be as likely to be 
successful as had been the efforts to discover a perpetual motion. 
It therefore required no little courage to appear before the public 
as the founder of a Balloon Club with all its hopes and aspirations. 
Far-seeing men, like Moltke, looked forward to the future with 
confidence and prophesied great things for ballooning. On the 
other hand, a well-known scientific man stated in a lecture 
about that time that the idea of dirigible ballooning was an 


" unfortunate form of lunacy," and the organ of the club was 
spoken of as a " curiosity." 

The well-known painter, Arnold Bocklin, took an active part 
in the practical work of the club,^ but without any great success. 
He made a flying machine in the form of a Hargrave box- 
kite, and thought to rise or fall by altering the position of the 
sails, trusting to the wind for any forward movement. He 
entirely forgot that a kite could only rise if held at the end of a 
string. He invited Colonel Buchholtz, who commanded the first 
Balloon Corps, to witness an experiment on the Tempelhof er Feld ; 
the apparatus finally succeeded in rising a foot from the ground, 
qknd was then broken to pieces. Bocklin always defended his 
ideas with much vigorous argument, but did not continue his 

The club made great advances when the meteorologist, 
Professor Assmann, was elected president in 1890, and was able 
to interest the Kaiser in its proceedings. A large sum of money, 
placed at the disposal of the club by the Kaiser, enabled a 
series of ascents to be carried out according to Assmann's 
plans, the results of which have opened new prospects for 
scientific ballooning. These will be discussed in a later 

In addition to its scientific activity, a great deal was done to 
develop ballooning as a sport. A large number of expeditions 
were organised by Captain von Sigsfeld and Major von Tschudi, 
amounting now to nearly one hundred every year. This con- 
tributed to arouse a general interest in the matter. Since the 
spring of 1902, the president's chair has been occupied by Pro- 
fessor Busley, who has devoted himself with great energy to the 
sport. He contributed largely to the foundation of the German 
Balloonists' Federation, which led the way for the long-cherished 
French scheme of the '' Federation Aeronautique Internationale." 
The Kaiser showed his further interest in the proceedings of the 
club by attending a lecture on the French dirigible balloons in 
December, 1905, and presented a prize for a long-distance race, 

1 See " Twenty-five Years in the History of the Berlin Balloon Club," by H. W. L. 
Moedebeck, 1906. Published by K. J. Trubner, Strassburg. 



which was won on October 14th, 1905, by Dr. Brockelmann, in 
the balloon " Ernst." 

Many people fail to see bow ballooning can properly be termed 
s sport, seeing that the airship is entirely at the mercy of the 
wind, provided, of coarse, it is not of a dirigible type. Tbey 
leave out of acconnt the fact that much practice and experience 
give the aeronaut such control over hia surroundings that he is 
at any rate not so helpless as a mere novice, whose only idea 
seeme to be to make as long a 
journey as possible. The 
longest journey made in a 
balloon was that undertaken 
by Count de la Vaulx and 
Count Castillon de Saint 
Victor, in 1906, with the 
" Centaur," which had a 
capacity of only 66,000 cubic 
feet. They started from Paris 
and landed at Eorostischeff 
in Russia. The distance, as 
the crow flies.was 1,200 miles, 
and the journey lasted 853 
hours. In so far as length 
of time is concerned, the 
longest expedition was under- 
taken by Dr. Wegener of the 
observatory at Linden berg, 
on April 5th, 1905, when he remained in the air for 52^ hours. 
Another long expedition was undertaken by Professor Berson 
and Dr. Elias, who made an ascent for meteorological purposes, 
and travellel from Berlin to EiefT in Russia, a distance of about 
930 miles. 

The ascent made by the French aeronaut Godard in 1897 
caused a good deal of excitement. He started from Leipsic with 
seven passengers, in a balloon of a capacity of 100,000 cubic 
feet, and landed at Wilna. He stated that he had passed above 
the clondB over a number of large towns in the east of Germany, 


and had covered 1,080 miles. A record of this kind is of no 
value ; the determining factor is the distance in a straight line 
from start to finish, seeing that there is obviously no means of 
checking any statement as to distances covered above the clouds. 
It is indeed possible to determine one*s actual position by astro- 
nomical means, even if the balloon is above the clouds and the 
earth is out of sight ; but evidence of this kind is apt to be 
somewhat inconclusive. 

The compass is of no use for mapping out the course of a 
balloon above the clouds. If the balloonist is moving at the 
same rate as the clouds, it would appear to be absolutely at rest. 
It would therefore be impossible to tell in what direction he is 
moving or at what rate. He knows whether the north is on the 
right or left ; but beyond this, the compass has no information 
to give. Let us suppose that the clouds appear to be travelling 
towards the east. Then it is either possible that the clouds are 
actually moving towards the east and that the balloon is moving 
slower, or on the other hand the clouds may be standing still or 
moving towards the west, while the balloon is moving much 
faster towards the west. The information could therefore only 
point decidedly to the fact that the wind is either in the east or 
in the west. Such a fact might certainly be useful if there were 
any danger of falling into the sea ; and supposing the start had 
been made at Berlin, it would be evident that the journey could 
be continued without anxiety. The aeronaut is in any case 
liable to most sudden surprises. At great heights changes in 
the direction of the wind are very frequent. In the northern 
hemisphere, the wind usually veers in the direction of the hands 
of a clock; in the southern hemisphere, the reverse is the 

Generally speaking, the length of a journey is a matter of 
accident ; without the necessary wind, it is impossible for the 
greatest dexterity to be of any use. Skill can be shown, if 
several balloons ascend at the same moment and it is a question 
as to who can remain in the air for the longest time, in which 
case it is necessary to be as sparing with the use of ballast as 
possible. Handicaps can be arranged by adjusting the amount 


of ballast to the size of the balloon, and allowances can also be 
made for the kind of gas with which the several balloonB are 
filled, though generally the gas would be the same in all cases. 
Boles have been drawn up by the Federation A^ronautique 
Internationale, governing the conditions of competitions, and 
these have received the approval of all the clubs represented at 

Fia. 123.— A bank of doads. 

the conference. The first race for the Gordon-Bennet prize took 
place on September SOth, 1906, and was won by Lieutenant 
Lahm, an American competitor. A second competition was held 
at Berlin on October 14th, and was won by Dr. Brockelmann. 

Theoretically we know that a large balloon loses more gas 
than a small one ; all balloons do not, therefore, require the 
same amount of ballast, which must be distributed somewhat in 
proportion to their sizes. A big balloon is not so easily managed 
ae a smaller one ; as it descends it gets up a greater speed, and 


therefore more ballast must be thrown out to neutraliae this. 
It is often said that the main thing which requires skill is to 
find a level at which there is a stifF breeze. But this a counsel 
of perfection. It the driver sees from the flight of the clouds, 
or from the pilot balloon, that the breeze is stronger at a higher 
level, be can throw out ballast, provided he has a sufficiency, 
and rise to that level. But the converse is not possible. If he 
sees from his bits of paper that the breeze is stronger at a lower 
level, be cbd open the valve and descend to that level, but, as 
already explained, it is not generally possible to remain at that 

FlO. 126. — Balloon alter the r[ppmg-cord has been pulled, 
altitude. Under normal conditions, a falling balloon goes right 
down to the ground. If the fall is checked in any way, the 
balloon will rise again to the same height as that from which it 
has fallen, and may even go higher than before. Moreover, 
experiments of this kind must be paid for in gas and ballast, 
and therefore tend indirectly to lessen the distance which it is 
possible to cover. 

The fastest journey in a balloon was made from Paris at the 
time of the siege. The distance from Paris to the Zuyder Zee, 
amounting to 265 miles, was covered in three hours, at an average 
speed of ninety-five miles an hour. The greatest speed over a 
short distance was probably attained by Captain von Sigsfeld 


and Dr. Linke on their fatal journey from Berlin to Antwerp, 
when a velocity of 12S miles an hour was recorded. 

In Gompetitions over great difltances or for great lengths of 
time, it IB very important not to get worn out. At night time it 
is a good plan to take it in turns, and for one to sleep in the 
intervale. Warm clothing ia an absolate necessity, as the cold 
may be sufficient to prevent a man from sleeping. Shonld the 
provisions run short, that may be an even more serious calamity, 
and it is generally found that something hot to eat and drink 

Fio. 127,— The Bofburg, VieDn*. 

FhoMgnpb by C«pUiD HlntsntoiiHr 

would add to the pleasures of existence. But fires are an 
impossibility, and enterprising persons have therefore thought- 
fully provided the aeronaut with a variety of tinned provisions 
which can be cooked by adding water to the quicklime with which 
the tins are surrounded. 

Injury to health may result from an ascent to a great height, 
and therefore competitions of this kind are not organised. But 
races are started with a view to reaching a definite place, the 
winner being the man who comes nearest to the mark. Naturally 
in this case everything depends on the direction of the wind, 
which most be ascertained before the start by means o( a pilot 
balloon. Motor cars can be set to chase and capture a balloon. 


and many other forms of competition maybe organised, of which 
examples may be found in Moedebeck's Handbook. Ballooning 
is the most exhilarating of all forms of sport ; the impressions 
of the journey excite the imagination, and there is also a certain 
charm in knowing so little about the journey's end. Before the 
start pilot balloons are sent up, the speed of the wind noted, 
and every likely contingency carefully weighed; plans for the 
evening's arrangements are then made. But prophecy is a 
gratuitous form of error, and calculations of this kind are equally 
waste labour. Nothing generally happens in the course of the 
day's march except the unexpected. 

It seems to be generally supposed that ballooning must cause 
a sensation of giddiness, and one is often asked as to the sensa- 
tions experienced in travelling at a furious speed through the 
air. It is, however, a curious fact that persons who suffer from 
giddiness under ordinary circumstances entirely lose the sensation 
in the basket of a balloon. Perhaps this is due to the fact that 
it is impossible to form any precise estimate of the height ; the 
basket is so small and the height so great, it seems impossible 
to compare the two. Moreover the guide-rope always seems to 
touch the ground. The following incident is an illustration of 
this fact. A certain man, who suffered from giddiness to such 
an extent that he was scarcely able to look out of the window of a 
room on the first floor, was induced , for the purposes of a bet, to 
undertake a trip in a balloon. After two hours he was able to 
get up from his seat in the corner, and cautiously look at the 
horizon from the middle of the car. At a later stage he was 
able to look over the edge of the basket without any feeling of 
anxiety or giddiness ; but when he reached the ground he was 
just as bad as before. 

In a free balloon there is no sensation of sea-sickness, as the 
balloon floats gently along; but with a captive balloon things 
are very different on a windy day, and sooner or later everybody 
succumbs. The first ascent offers curious sensations for the 
novice. He seems to see the earth sinking away from him, and 
when he comes down again, the trees and houses rush to meet 
him and welcome him back. The speed can be estimated by 



Ci 7 

'S '' ,, 


noting the time which it takes to reach places on the map, bnt 
an experienced balloonist can generally make a fairly accurate 


guess. The height affects the apparent speed, and must ) 
taken into account. 

In the year 1899 Captain von Sigsfeld made an ascent in t 
company of the author and Herr von Haxthausen, and t 
incidents of this journey may be of interest to the read 
The balloon started in clear weather from Berlin, and reach 
Breslau in two hours, the speed having been about 92 miles \ 
hour. The start had been made under difficulties, and no kii 
of proper balance was possible, seeing that the balloon wt 
almost thrown to the ground by the wind. Ordinarily, after th 
passengers have taken their places, the ballast is loaded into th 
car until the "lift " appears to be reasonable. If the balloon seem 
inclined to rise too fast when the ropes are somewhat slackened 
ballast must be put in the car ; on the other hand, if it seemt 
too heavy, it must be correspondingly lightened. During thit 
stage it is important to keep the balloon vertically above the car, 
as otherwise it is not possible to form any exact estimate of the 
lift. In a strong wind this balancing is a difficult business, and 
requires great experience. Sigsfeld, however, gave the order to 
let go ; and we were immediately bumped along the ground by 
the wind, and did not succeed in rising till we had thrown out 
two sacks of ballast. The balloon then rose at once to a height of 
about 2,500 ft. The inflating tube is opened just before the start, 
and is kept closed till the last moment, as otherwise the wind 
would drive too much gas out of the envelope. If it should 
happen that the inflating tube has not been opened, the rule is 
to empty the balloon, because otherwise it would rise to a great 
height and burst, and it is seldom safe to trust to letting out the 
gas by the valve. 

The view which met our eyes was magnificent, and the great 
speed caused a rapid succession of varied landscapes. An 
express train, going from Berlin to Breslau, seemed to us to be 
going in the opposite direction, and was soon out of sight. In 
all we had 12 sacks of ballast, and seeing that the weather was 
very cloudy, and the balloon had only been inflated with coal 
gas, it did not look as though the trip was likely to be a long 
one. But in spite of the strong wind, the balloon sailed quite 


steadily along, and every now and then a few handfuls of ballast 
were thrown out in order to keep to a level of 6,000 ft. We 
wanted to remain where we were because it was colder below 
with a wind blowing more in the direction of Russia, which we 
had no intention of visiting. The Austrian frontier was passed 
between Dab and Ghelm, and soon our stock of maps was 
exhausted. A small hand-atlas was our only resource, and 
was probably as useful as full-sized maps would have been, so 
great was the speed. The Tatra range was as clear as could be 
away towards the S.S.E., and the balloon, flying at full speed 
over the hills and valleys, soon reached the Carpathian Moun- 
tains. Eddies now began to be noticed, and this made travelling 
less pleasant. Soon we had a remarkable experience, which 
Sigsfeld duly recorded in the notebook. A slight vertical 
movement towards the back was noticed in the car. The 
balloon was soon thrown about in all directions, and finally 
rotated at a considerable speed. The guide-rope and the four 
holding-ropes became completely entangled; but at the end 
of a minute it all passed off. Soon after the guide-rope struck 
against some trees and made a great noise, which we thought 
at first was the sound of rifle firing. 

The next place we clearly recognised was Neu-Sandec, near 
the mountains of Galicia. The place was only seen after passing 
the heights of Ghemiecka-ga, and it was therefore impossible 
to land owing to the great speed. We thought it might be 
possible to find another track on the other side of the Car- 
pathians, but this idea had to be given up, because the mist 
and fog made it at times almost impossible to see anything. 
The valve was therefore opened, and in a side valley, immediately 
to the south of Bogusza, the ripping cord was pulled at a height 
of 80 feet. We landed in deep snow after being bumped along 
the ground for about 20 yards ; luckily the hills broke the 
violence of the wind. Just before landing we noticed two men, 
who appeared to be following the balloon. We shouted to them 
to come and help, and also blew our torpedo-boat whistles ; but 
they were nowhere to be seen. At last we found them hidden 
away behind a stack of wood, trembling from head to foot. 


They said that they had never seen a balloon in their lives 
before, and supposed that it must contain some emissary of the 
devil; and the unearthly noise made by the guide-rope as it 
crashed through the trees had only added to their fright. 
Gradually they took courage when they saw that the balloon 
had almost disappeared in the snow, and fetched other wood- 
choppers to come and help. Finally the packing was finished 
after many misunderstandings, mainly due to our imperfect 
knowledge of the local dialect, and the balloon was put on a 
sledge and taken to the village. Here we were informed by the 
local magistrate that our journey was to end, and that we must 
consider ourselves under arrest ; our movements were indeed so 
suspicious that we could be nothing better than spies, and his 
opinion would probably be confirmed by his superior authorities 
in the course of a few days. We protested loudly and showed 
him our passports, but this was of no use. The magistrate was 
unable to read German, and consequently our passports were 
little better than waste paper. He refused to send a telegram 
to headquarters, and believing us to be Russian officers, treated 
us with scant courtesy. Nothing remained but to do as we were 
told. We put up in a room of the village inn, which was the 
only available accommodation, and devised a plan by which we 
were to get the help of one of the villagers who could speak a 
little German, and send a telegram to our ambassador at Vienna. 
The man had already done what he could on our behalf, and 
he was readily induced to act as guide. Under cover of dark- 
ness, about 6.80 p.m., we left the house, and went on foot to 
Kamionkawielka, where was the nearest telegraph office. The 
snow had begun to melt, and the road crossed a little swollen 
stream about ten times. Sometimes there was nothing better 
than a ford, and sometimes the trunk of a tree served as a 
slippery bridge. It was now pitch dark, and rain was falling 
heavily. We reached the telegraph office in three hours, and 
sent a telegram to the magistrate at Grybow, seeing that it was 
in his province we had made our unlucky descent. It was 
thought unwise to telegraph to the German Embassy according 
to our original plan, and we therefore asked the authorities at 



Grybow to iDstract the magietrate who had arrested ub to 
tlie effect that he waa to let ua go and hand over to us all 
our goods and 

I thereupon 
began the return 
journey, and was 
persuaded bymy 
guide to spend 
the night at his 
house, which was 
in a wood at a 
short distance 
from the high 
road. The kit- 
chen of his house 
was occupied by 
a variety of aui- 
mals, and the 
other apartment 
wasof thenature 
of a bed-sitting- 
room for the 
entire family, 
which included 
children, par- 
ents, and grand- 
parents. Amid 
such surround- 
ings, I was only 
able to eat a 
couple of eggs, 

though in reality I was very hungry. Violent gesticulations 
followed, and I was ultimately led to understand that this hos- 
pitality mast be paid tor on the spot, though the sum demanded 
seemed somewhat out of proportion to the benefits received — at 
least so I thought. A very small room, ordinarily occupied by 

FiQ. 129.— Water ftochor for balloon. 

(From " Dl« Unuchiu.") 


the head of the family, was assigned to me as a bedroom, and I 
was invited to retire. So I laid myself on the bed in full uniform 
with my sword at a convenient distance, as I could not help 
feeling that the continued whispers of father and son were not 
reassuring. The situation was certainly not very encouraging. 
I was in a shanty, away from the high road, in the middle of 
the Carpathians, among people who looked almost like brigands. 
Not a word of their language could I understand. They probably 
knew I had some money about me, and my sleepy head was soon 
full of all the highwaymen of whom I had ever heard. What 
added to my suspicions was the fact that every now and then 
the father came to the curtain, which served as the door, and 
peeped in to see whether I was asleep. Naturally enough I 
suspected him of the most sinister designs, and clutched at my 
sword as soon as I heard his footsteps. Luckily this state of 
tension came to an end about 12.80 a.m., when there was a 
knock at the front door, and an Austrian policeman demanded 
to know whether I was there. The authorities at Grybow had 
sent the man in answer to my telegram with instructions to do 
what was wanted, and accordingly he was on his way at the dead 
of night. He reassured me as to the character of my hosts, and 
said that their account of the matter was they supposed I was 
going to kill tliem^ otherwise why did I take my sword to bed 
with me. Now I began to understand the stealthy visits of the 
father, who had only been anxious all the time to see that I was 
not meditating a descent upon his unprotected family. The 
gendarme left about 1 a.m., and I was soon asleep. 

The next day I went to Grybow, where general indignation 
was expressed at the proceedings of the magistrate at Bogusza. 
This worthy was not a little surprised at the turn events had 
taken, and did his best to make amends by providing a sledge 
with six oxen to carry the balloon to Grybow, where Sigsfeld and 
Haxthausen arrived in the course of the afternoon after a very 
toilsome journey. All's well that ends well. We were received 
in the most friendly manner at Grybow, but notwithstanding 
this, we should recommend the balloonist to steer clear of the 
backwoods in the Carpathian Mountains. • Still, it must be 



n Austria ; 

admitted that this sort of accident is very uncommon ii 

in Russia difficulties sometimes arise. It is not i 

Russia to receive the most hospitable welcomo on landing, but to 

be obliged to submit to a most wearisome croBs-eKamination 

before being allowed to depart. Still, it is part of a balloonist'a 

business to learn to extricate himself from tight places of one 

kind and another, and if he should have the misfortune to be 

involved in any such 

adventure, he can con- i — . , 'n ■ — 

sole himself with the Ma^^ ■, . 

reflection that variety 

is the spice of life. 

Much enjoyment is 
to be derived from a 
journey over a large 
expanse of water. 
There is undoubtedly 
some danger attached 
to it, for descents into 
water are always at- 
tended with risk. The 
most usual trip of this 
kind has been acrosB 
the English Channel, 
and oddly enough, the 
start lias generally 
been made from the 
French coast. The direction of the wind is not so important in 
going from Dover to Calais as it is if the journey is made in the 
opposite direction. In the one case, the wind may veer through 
nearly 90 degrees on either side before the balloon would be 
carried out to sea ; whereas in going from Calais, a deviation of 
45 degrees would be sufficient to prevent a landing. 

An Englishman, named Green, proposed in 1837 to fasten a 
number of buckets to the guide rope, and drag them through the 
water. He tliought this would help him to guide the balloon, 
but he would naturally only be helped by such local currents 


as existed. A Frenchman, named I'Hoste, experimented with 
similar dragging devices. He made aeveral trips, of which the 

tbe Aledit«rraneiiii 

most remarkable vere those from Cherbourg to London and from 
Calais to Yarmouth. But on November ISth, 1887, 1'Hoste and 
his companion, named Mangot, were drowned. One of his 

Fio. 132. — Basket of Count dc la Vauli' balloon, allowing the deTJatOR. 

countrymen, named Herve, continued these experiments, and 
made many successful expeditions. He used Soating timbers in 
conjunction with sails, and succeeded in producing a deviation 
of about 70 degrees from the direction of the wind. Such 



" deviatora " consist of a frame into which a number of straight 
or bent pieces of wood are fitted, one behind the other, somewhat 
after the fashion of a ladder. From the ends of this contrivance, 
ropes are taken to the balloon, by means of which the position 
of the rungs can be altered so as to present a. variable angle to 
the course of the balloon. If the rungs are placed parallel to 
the direction of Sight, the balloon is subjected to a slight braking 

FiQ. 133.— Coaut de la Vaali' deviator 

action, but the direction of its course is unaffected. If the 
rungs are placed obliquely, the resistance, due to the water, is 
increased, and the balloon's course is deflected to that side on 
which the rope has been shortened. 

Count de la Vaulx has a balloon specially arranged for such 
water expeditions. He has an air-bag, which is not a necessity 
in the case of a free balloon ; but it helps to preserve the shape 
of the envelope, seeing that from some points of view bis balloon 
may be considered ae being of the captive type. Many failures 



have resulted, but a man of his energy is not easily beaten. The 
car of his balloon also contains a small motor for driving a pro- 
peller. His plans have been well laid, and he thinks there is no 
danger in making a descent on the water. His water-anchor 
produces such a braking action that in case of need the 
accompanying steamship could easily overtake him. Others 
have talked about crossing the Atlantic ; but schemes of this kind 
are too much in the air to be worth serious discussion. Several 
attempts have been made to cross the sea from Germany, but 
these have mostly been in the neighbourhood of Kiel or Jutland, 
where there are a number of islands convenient for a descent. 

Fig. 134. — Deviator offering the maximum resistance. 

(Prom *' Die Umschau.") 

But such trips have no real value, and the risk of coming into 
the water is too great to justify them in most cases, though an 
exception may certainly be made if there is some distinct 
scientific object in view. Two soldiers belonging to the Prussian 
Balloon Corps were n^^rly drowned on March 24th, 1906. They 
had been for some time above the cloud level, and on descending 
found they were over the Baltic. All instruments were thrown 
away, the basket was cut adrift, and they even threw away some 
of their clothing. Finally the balloon drifted over the land near 
Earlskrona ; if the course had been a little more to the east, they 
would undoubtedly have been drowned. 

A change in the direction of the wind may bring serious 
consequences, and the dangers of a journey across the sea may 
be well illustrated by an account of a journey which the author 




made with the meteorologist Berson of Berlin, on January 10th, 
1901. The start was made at Berlin, and the descent took place 
at Markaryd in Sweden. There were many lucky circumstances 
in connection with the journey across the sea. In the first 
instance it was intended to make a high ascent, and the basket 
was furnished with instruments for this purpose. But the sky 
was cloudless, and it seemed likely to be possible to remain at a 
moderate altitude for some time without any great loss of ballast. 
The idea of crossing the sea was then considered, and the original 
plan was given up. The first consideration was to be able to 

Fio. 135. — Deviator offeriDg the minimam resistance. 

(From "Die Umschau.") 

reach the coast with a sufficiency of ballast, but other things had 
also to be taken into account. Generally speaking, the balloons 
which start from Berlin have lost too much ballast by the time 
they reach the coast to make it possible to continue the journey. 
A fortunate circumstance in connection with our journey was the 
fact that the wind was blowing towards the north, and at a low 
level it was indeed blowing towards the north-west. The usual 
wind is from the south-west over the northern hemisphere, and 
this carries a balloon from Berlin too far towards the east to 
make it possible to cross the sea. We were also able to judge, 
from the time at which we arrived at the coast of the Baltic, that 
we should be able to cross the Baltic in daylight, supposing that 



the wind did not drop. As a matter of fact, we did not actually 
reach Trelleborg till after dusk, though under the eircumatances 
we were, I think, justified in undertaking the journey. Both of 
us might fairly 
be considered to 
have had experi- 
ence in the work, 
and we agreed 
that the crossing 
might safely be 
undertaken ; so 
that had any ac- 
cident resulted, 
neither would 
have had to 
reproach himself 
with having alone 
undertaken the 
responsibility. It 
generally hap- 
pens that on a 
balloon there is 
one experienced 
aeronaut, and 
the rest of the 
passengers are 
without any 
special experi- 
ence. It is there- 
fore impossible 
to submit any 
proposal to the 

Flo. 136.— Map showing Ihe course ot Ihe balloon 
from Itcrlin to Markaryil. 

vote, even though the passeDgers have already made several 
trips and will in time become experienced men. The man 
who leads tlie expedition lias to bear all the responsibility 
in caB6 of accident, and should it appear that he has not 
given the word of command with sufficient emphasis in an 


emergency, he ia likely to lay him- 
self open to the Bevereet censure. 

The expedition was intended to 
be devoted to meteorological pur- 
poses, and the basket, which was 
very small and uncomfortable, was 
fitted out with the requisite instru- 
menls. We had warm clothing, and 
a stock of provisions, and set sail 
accordingly at 8.17 a.m. The 
temperature at Berlin was 21° F., 
and elsewhere it was colder still. 
The balloon passed from Berlin 
over the targets at Tegel at a height 
of 600 to 600 ft, where a second 
balloon with recording instruments 
was sent up from the Aeronautical 
Observatory. We soon found that 
at levels below 2,500 ft. we were 
being driven very slightly towards 
the west, at levels between 2,500 
and 4,500 ft. the course was due 
north, and at still higher levels there 
was a slight tendency towards the 
east. The temperature, too, rose so 
much that we were glad to do with- 
out our furs. Ata level of S,000 ft. 
the temperature was 27° higher 
than on the ground. Generally the 
air gets colder at higher levels ; it 
is usual to expect a decrease of |° 
or ^° in a rise of 100 ft., and therefore 
in the present case we might have 
expected to find the thermometer 
nearly down to zero. As a matter 
of fact the thermometer did not 
sink to the freezing point till we 



reached an altitude of 8,000 ft., and at 10,000 ft. we reached 
again the temperature of the ground level. We were unable 
to read the lowest temperature, because there was no light, 
and we had not provided ourselves with an electric lamp. The 
sky was cloudless, except for a small amount of cirrus which 
seemed to be at a great height. A thin mist covered the 
ground, and the balloon floated above it without throwing out 
any ballast. Herr Berson had studied the state of the weather 
on the evening before the start, and it was seen that there 
was a steady south-easterly wind over all the parts between 
Berlin and the north-west. It therefore seemed likely that it 
might be possible to cross the Baltic, and we consequently took 
maps of Denmark and the south of Sweden. He told me his 
plan after we had been under weigh for an hour and had reached 
the Finow Canal. The various possibilities were discussed, and 
the fact that the wind was more westerly at a lower level was 
much in our favour. It seemed certain that in any case we 
could reach Denmark, as our speed was about 25 miles an hour. 
Our only fear was that we might have a long journey over the sea 
slightly towards the east of Denmark ; but there seemed to be 
no reasonable probability of the wind shifting to the east and 
carrying us therefore right out into the open sea, which would 
expose us to a most serious risk. We did not make up our minds 
all at once ; it was at a later stage, when we reached Neustrelitz, 
that we definitely resolved after further careful deliberation to 
cross the Baltic. The view from the balloon was splendid ; we 
heard a peculiar, dull sound as we crossed small lakes with their 
thin covering of ice, caused, as we supposed, by the cracking of 
the ice. Every now and then we heard shouts of the beaters at 
a shoot ; but otherwise nothing broke the stillness of the air. 
In fact it seemed to me as if this journey was much quieter 
than usual ; we seldom heard the wheels of a cart or the shouts 
of the schoolboys ; ordinarily the balloon is greeted with shouts 
at every village it passes. The pigeons, as usual, were terribly 
frightened ; no doubt they think that a balloon is some gigantic 
bird of prey, and fancy there is safety in numbers. 

Tlie recording balloon was at a great height above our own, and 



\^as partly hidden in consequence. Suddenly there was a great 
jolt, and a peculiar noise drew our attention to the fact that one 
of our sacks of ballast on the outside of the car had tumbled off » 
and that we had suddenly been shot up a few hundred feet, which 
was the last thing that we had intended to do. This point was 
duly noted on the curve which recorded our height by a sudden 
upward bob between 10 a.m. and 11 a.m. We passed Neustrelitz 
and Demmin on our left, and Neubrandenburg on our right. At 
1.15 we reached the coast at Stralsund, and passed Biigen. We 
could see a number of fishers with their nets on the ice, trying 
to catch fish out of the holes. At Stralsund the water was also 
frozen ; we could clearly see the channel for the ferry boat between 
Stralsund and Eiigen. At two o'clock Biigen was left in the rear, 
and we were over the open sea. The Baltic was free from ice, 
and fairly calm ; but we could see the foam of the waves, which 
glistened brightly. There were multitudes of gulls, who were 
much perturbed at our appearance and flew anxiously hither and 
thither. We fixed our precise position on the map, and it seemed 
that we had come slightly to the east, but not sufficiently to 
cause any anxiety. 

The view over Biigen and the chalk cliffs of Stubbenkammer 
and Arkona was splendid ; the atmosphere was perfectly clear. 
On the horizon we could see the coasts of Sweden and Denmark, 
looking almost like a thin mist ; east and west there was nothing 
but the open sea. About 3.15 the balloon was in the middle of 
the Baltic ; right in the distance we could just see Biigen and 
Sweden. The setting of the sun at 4 p.m. was a truly 
magnificent spectacle. At a height of 5,250 ft., in a perfectly 
clear atmosphere, the effect was superb. The blaze of colour 
was dimly reflected in the east by streaks of a bluish-green. I 
have seen sunsets over France at heights of 10,000 ft., wuth the 
Alps, the Juras, and the Vosges mountains in the distance ; but 
this was quite as fine. The sunsets seen by the mountaineer or 
sailor are doubtless magnificent ; but I hardly think the spectacle 
can be finer than that spread out before the gaze of the bal- 
loonist. The impression was increased by the absolute stillness 
which prevailed ; no sound of any kind was to be heard. As 


soon as the sun went down, it was necessary to throw out some 
ballast owing to the decrease of the temperature. The highest 
temperature registered by the black-bulb thermometer was 79° F., 
the balloon being at that time over the Baltic. Now it could be 
put away, as there was no more work for it to do. Even with 
the compass we could not tell in what direction we were moving ; 
the guide-rope was trailing through the water, but it was useless 
for telling the direction of the motion. .We noticed the direction 
in which the sand seemed to fall when we threw out the ballast. 
At a great height we concluded that we were being driven 
towards the east very slightly; at lower levels the tendency 
was towards the west. It therefore seemed clear that if the 
conditions remained unaltered we should be driven slightly 
towards the east. But this had to be prevented at all costs, 
and we therefore kept as high as possible in order to get a whiff 
of the easterly breeze. Soon land came in sight. During the 
three hours we had been over the water we only saw two 
steamers. One of them directed its course towards us at 
first, as we thought ; but soon it went on its way, as it seemed 
we had no need of help. It is useless for the aeronaut to reckon 
on help from a steamboat under such circumstances. It is not 
every steamboat that can come far out of its course on the cff- 
chance that help is needed; besides which, the difference of 
speeds may be so great that help, if it does arrive, would be too 

We reached the Swedish coast about 5 o'clock, and passed 
over Trelleborg at a height of 2,000 ft. The question then arose 
as to whether to land, or to continue during the night. Although 
it was well past sunset, there was sufficient light in consequence 
of the snow to see our way to the ground, and to land quite 
easily. It is always a little awkward to land in a strange 
country after dark; moreover, we wanted to do more meteorological 
work. It was thought there was still sufficient ballast to take us 
up to a much greater height, even allowing for necessary losses, 
and the balance of the arguments seemed to be in favour of 
deferring the descent. We therefore proposed to continue for 
another sixteen hours during the night in spite of the cold. We 




were able to see a good distance ahead, and i( we should reach 
the sea either on the east or the west, there would be plenty of 
time to descend before we should be in any serions danger. 

We were now quite low down, and going almost direct for 
Malmo, which would probably be left on the right-hand side. 
But this did not suit our plans, as n drift towards the west might 

Fig. 138.— Stockholm seen from an altitude of 3 
{Pholognph by Oalur Uildin.) 


bring ua over tlie sea long before the fifteen hours were over, 
therefore threw out a lot of ballast and rose higher than ever, 
getting into a southerly breeze. Malmu was therefore passed on 
the left, and the university town of Lund on the right. After 
this the map was of no further use, as it was quite dark and we 
had DO lamp. The whole outlook was like a transformation scene. 
Floods of light rose up from Trelleborg, Malmo, Copenhagen, 
Lnndskrona, Lund, Elsinore, and Helsingborg, while the little 


toniiB beneath our feet sparkled with man; lights. We were now 
at a height of more than 10,000 ft. and-eonsequently all these 
places were within sight. The glistening effect of tlie snow was 
heightened by the hlaze which poured from the lighthouses along 
the coasts of Sweden and Denmark. The eight was as wonderful 
ae that of the sunset had been, though of a totally different 
nature. We supposed the light in Malmo to be from arc lamps; 

Fia. 139. — Mischabclhorn, seen from the east, shoning aUo the Fee and 

Hobbalen glaciers. 

(PhoU«i»ph by Spf Uerini > 

its brightness was very marked. We found later on visiting the 
town that there was no electric light in the streets, but only 
Welsbach burners ; yet the effect produced in the distance was 
really brilliant. The Pole-star was our guiding light; the com- 
pass was useless in the dark. We also guided ourselves to some 
extent by the lights below, and as soon as we saw that the course 
was not due north, more ballast was thrown out, and at once 
we got again into the southerly breeze. There seemed now to 
be no tendency to drift towards the east. 


Sometimes there was a slight mist on the ground, but this 
obstructed the outlook very little. Soon we were struck by the 
fact that the earth seemed to be covered with dark patches. Herr 
Berson thought there were clouds beneath us, through which, 
here and there, we could see the shining snow. I had better 
eyes than he had, and thought I could see lights in these dark 
patches. My theory was that the dark spots were villages where 
the snow had melted, but we soon found this was not so. Gradu- 
ally everything disappeared beneath us, and it was evident that 
the clouds had closed up, covering the earth from our sight. 
What was to be done ? The blaze from the lighthouse in the 
Bay of Halmstadt had been too close to be pleasant. We were 
moving rather to the west than to the east. It was just possible 
to see the pointer on the aneroid, but even supposing we kept 
at the same level we might quite easily get into a current and 
be carried to the west. The only prudent thing to do was to 
come down at once, and this we did. We found out later from 
the weather-chart, published that evening, that in the middle of 
Sweden and south-east of Norway a north-east wind was blow- 
ing at 8 p.m., while in Copenhagen, the Kattegat, and Jutland 
it was from the south or south-east. If we had continued, we 
should have been carried across the Kattegat and Skagerrack 
into the North Sea, and sooner or later the balloon would have 
been at the mercy of the waves. 

The valve was opened and the balloon descended through the 
thick clouds. We could see nothing, but the little jerks showed 
us that the guide-rope was touching the ground. In a few 
seconds we saw the ground, and soon learnt that we were 
descending into a forest which enclosed a number of small 
lakes. At once more ballast was thrown out, and we skimmed 
along over the tops of the trees. Soon we crossed a big lake, 
and saw a place that seemed suitable for a descent. The valve 
was then opened, both of us gave a tug at the ripping cord, and 
after a few bumps we found ourselves on the ground. W^e had 
come down in deep snow on the side of a wood, about 14 miles 
from the railway station at Markaryd, in the province of Smaa- 
land. We packed up our instruments, and began to look out for 


a cottage; but this is not always an easy task in the dead of 
night in a foreign country. In a quarter of an hour, we found 
a farm, and succeeded in rousing the inmates. A much more 
difficult job was to induce them to open their front door. Here 
were two men, talking some sort of double Dutch, who suddenly 
appeared at a farmyard, miles off the high road in the middle of 
the night, and demanded admittance. Berson can talk six 
languages, but unfortunately Swedish was not among them. 
Our situation was far from pleasant. Berson begged in the 
most humble way for shelter, while I contented myself with 
walking up and down, as I was unused to negotiations of this 
kind, and unable to add anything to his convincing arguments. 
We thought at least they might ultimately admit one of us. At 
the end of three-quarters of an hour the farmer, who turned 
out to be a very pleasant fellow, opened the door. We showed 
him some pictures of a balloon we luckily had with us, and they 
then began to understand the situation. We were then received 
with truly Swedish hospitality, and provided with supper. They 
even proposed to let us have their beds ; but this we naturally 
declined with many thanks. After supper we set out to search 
for the balloon, and were guided by the son and daughters of the 
family, who brought a lantern with them. It was soon found 
and rolled up as well as was possible under the circumstances ; 
the instruments and maps were more carefully packed. We 
then wended our way back to the farmhouse. The yard con- 
tained hens, pigs, cows, and sheep ; an empty corner was found, 
which was well packed with straw, and served as a couch for our 
tired limbs. We covered ourselves with great-coats, and tried to 
sleep. But the temperature was 10° Fahr., and as the place was 
only an outhouse with the boards roughly nailed together, and 
the wind whistling through the cracks and crevices, we were not 
sorry when the daylight came. We got up and were glad to 
warm ourselves before the fire, while they fetched some labourers 
from the next farm, which was a couple of miles off, to come 
and help us pack up our balloon. It was finally done, and we 
managed to make ourselves understood through talking English 
to one of the labourers, who had lived in America for some time. 



We then parted from oar host on the best of terms, and set otit 
on a sledge for the railway at Markaryd. Such an extraordinary 
cavalcade had never before been seen in those parts, or probably 
anywhere else for that matter. At the front was the basket ; at 
the back was the roUed-up envelope, boond round with the ropes, 
and standing up on edge, on the top of which we seated our- 
selves, one behind the other, and acted as drivers. We only 
regretted there was no camera to take a picture of the group. 
The rustics looked at us with open eyes, and probably thought 
my uniform looked a little strange amid its surroundings. They 
greeted us in friendly fashion, but realising that we were 
foreigners, they asked no questions. Our horse managed the 
hills remarkably well ; we switchbacked up and down, and the 
whole thing was done automatically without the driver's inter- 
ference. Every now and then it looked as though we should be 
landed in the snow, but the heavy balloon steadied it at the 
critical moment. Soon we reached a sort of high road, very 
hilly still, but better than before ; and after a drive of three 
hours, we landed safely at Markaryd at 5 p.m. We first went to 
the telegraph office to allay the anxiety of our friends, and after 
a long conversation, carried on for the most part in dumb show, 
we discovered that this was only a telephone office, and no tele- 
grams were taken in. But our troubles were near their end, for 
we found a stationmaster who was able to talk German. We 
handed him our messages, and he sent them by telephone to 
Hessleholm, whence they were forwarded by telegraph to Berlin. 
We paid off the driver, and packed the balloon on the train, being 
glad of an opportunity of getting something hot to eat and drink 
at the little railway hotel. 

Our messages evoked an unexpected response in the shape of 
telephonic enquiries from the Swedish newspapers at Malmo, 
Stockholm, Wexio, and other towns, which reached us long 
before our telegrams reached Berlin. Our balloon had been 
noticed as it came across the Baltic. Accordingly we gave 
particulars to the stationmaster, and he relieved us of any 

further bother. 

We reached Malnio next day, and I called on the officer 

A. Q 


commanding the regiment of hussars, which was stationed 
there. We were received in a most hospitable manner, and 
invited to join their mess, after which we were driven round 
Malmo and the neighbourhood before making our departure for 
Copenhagen on the way to Berlin. Our journey had been 
thoroughly interesting with its ups and downs, and we felt, even 
from the scientific point of view, to have collected facts of some 

A few figures will give some impression of our general results. 
The total distance travelled across the water was 77 miles, of 
which 50 miles was over the open sea. Our mean speed was 
81J ft. per second over the whole journey ; in Germany it was 
41 ft per second ; over the Baltic 83 ft. per second ; and in 
Sweden 25 ft. per second. The temperature at the moment of 
starting was 22° F. ; at a height of 2,200 ft. it was 40° F. ; 
at 8,200 ft. it was 44° F. ; and at 8,000 ft. it was at the 
freezing point. As for the recording balloon it started at 
8.3 a.m., and landed at 10 a.m. in Lychen, in the Uckermark, 
44 miles due north of Tegel, after a journey at the average speed 
of 42 ft. per second. The greatest height was 23,150 ft., where 
the temperature was 22° below zero. Its instruments showed 
also a temperature of 40° F. at a height of 4,800 ft., and the 
freezing point was reached at a level of 8,300 ft. 

A balloon expedition through the mountains is also a delight, 
and exposed to similar risks. Captain Spelterini is well known 
for his many journeys over the Alps. During the exhibition at 
Milan a prize was offered to the man who should succeed in 
crossing the Alps after starting from Milan. It was won by an 
Italian aeronaut named Usuelli, who succeeded in crossing over 
Mont Blanc. This can only be done in suitable weather, and 
it is very important to find out the direction of the currents at 
the higher levels by means of a pilot balloon before making a 
start. Anyhow it is necessary to rise to such a height as to be 
outside the range of the lower breezes, and to mount to altitudes 
of more than 20,000 ft. straight away. Steel cylinders containing 
oxygen must therefore form part of the outfit, which means a 
serious addition to the deadweight. There must be at least two, 



if not three, passengers ; consequently this woald require a 
balloon of 70,000 cabic feet capacity, wbicb muBt be filled with 

The first attempt was made by Spelterinion October Srd, 1898. 
Professor Heim and Dr. Maurer went with him in a balloon 
of a capacity of 115,000 cubic feet, named the "Vega." He 
stated from Sitten, and in 5^ hours he reached Riviere, in the 

Fio. UO.— The Lake of Lucerne. 
(Fhotognpb by SprllHlul.) 

department of the Haute-Marne, having covered a distance of 
140 miles. His idea had been to reach the Bodensee after 
crossing the Finsteraarhorn and the Urner and Glarner Alps. 
On August 1st, 1900, Spelterini started from the Eigifirst and 
crossed over Tiidi and Gliirniaeh. In 1903 he made an expedition 
from Zermatt and crossed the Dom in the Mischabel Chain, 
then turned towards the south-east over Lake Maggiore, and 
then after several turns to the Chinti, above Bignasco, where 
tiie descent was made. The most interesting expedition was in 


1904, over the Jungfrau, the Breithorn, the Blumli-Alp, and the 
Wildstrudel. The photographs which were taken on these 
occasions give a good impression of the pleasure which can be 
derived from journeyings in the Alps. 

It is difficult to describe the joy of this kind of ballooning to 

those who have not experienced it. In November, 1904, the 

author joined Captain Spelterini and Freiherr von Hewald in a 

trip from Zurich over the Lake of Lucerne, past the Rigi and 

Pilatus. We then went towards the south-west, and at heights 

of 13,000 ft. we passed over some of the bigger ranges. The 

weather was perfectly clear, and the mountains seemed so close 

as to be within a stone's throw. We passed the Jungfrau, the 

Eiger, the Monch, but the most beautiful thing we saw was the 

Great Aletsch Glacier, glistening in the sun. For three hours 

we experienced such delights as had never fallen to human lot 

before. There was always something fresh, some new feature 

in the panorama, and all spread out for us to enjoy in perfect 

stillness. We turned later to the north, and came to the ground 

on the north-west side of the Lake oE Neuchatel. The course 

was curious, inasmuch as it seldom happens that one passes 

along the Alps. Spelterini had himself never before had such 

luck. The turn to the right was an essential feature of the 

scheme, for our balloon had only a capacity of 55,000 cubic feet, 

and was filled with coal gas, and any attempt to cross the higher 

ranges was therefore impossible. Moreover, a landing effected 

at a great height is a very awkward affair, and is likely to cost 

a great deal of money. It need hardly be said that it is also 

about as dangerous as anything connected with ballooning can 

well be. But it is as well not to talk too much about " danger." 

The most erroneous notions exist about the risks attaching to 

the sport, largely because the newspapers easily convert trifling 

incidents into alarming accidents. The death of a jockey is 

dismissed in a few lines ; but the slightest accident to a 

balloonist seems to afford unlimited scope to the inventive and 

descriptive faculties. Professor Busley, President of the Berlin 

Balloon Club, read a paper on the supposed risks of ballooning with 

reference to the question of insurance. He showed that ballooning 


IB not much more dangerouB than any other sport, and that such 
accidents as occur are mostly due to the defective material used 
by the balloonists employed at country shows. He made a 
careful examination into the records of accidents which have 
happened to members of clubs affiliated to the German Associa- 
tion of Balloonists, and also to the Prussian and Bavarian Balloon 
Corps, and found that 36 accidents had happened as compared 
with a total number of 2,061 ascents. The injured amounted 
to 0*47 per cent, of the number of passengers, the total number 

VlQ. 141. — Balluon and ballooDialB on their wa; home. 

of whom was 7,570. But an improvement is even noticeable 
among professional aeronauts, and they are now beginning to 
know that confidence cannot be placed in an old patched balloon. 
Still they are not in a very enviable position ; their profession 
is a difficult one, and the profits are scanty. They cannot afford 
to keep a number of assistants, and have to trust to the intelli- 
gence of such local helpers as they can scrape together. It 
takes several hours to in£at« the balloon, and he is obliged to 
be present during the whole time because nobody else knows 
anything about it, and any delay at the last moment might 
expose him to the wrath of the mob. An amateur generally 
mounts into the basket after all the work of inflation has been 


done by experienced balloonists, whereas the professional has 
already done a hard day's work before the start is made. Con- 
sequently in a tight place he is at a great disadvantage. 
Professionals, too, have to make the ascent, whatever may be 
the state of the weather. In summer a thunderstorm often 
comes unexpectedly, and in the early morning, when the inflation 
begins, there may be no sign of the likelihood of anything of 
the sort. The professional has no great balance at the bank, 
and can ill afford to lose the money which is represented by the 
gas in the balloon. Besides which he would lose all the money of 
the crowd of sightseers if the show were abandoned. Therefore 
he is hardly in the position of a free agent, and makes an ascent 
under hazardous conditions. Still the authorities ought to be 
in a position to prevent an ascent when the conditions are 
unfavourable. It often happens that persons without any 
sufficient technical experience take upon themselves to announce 
balloon trips, and find unsuspecting passengers who may be 
exposed .to the greatest risks. If the professional chooses to run 
the chance of breaking his own bones, that is his aflfair ; but 
some means ought to be found of preventing him from involving 
others in his fate. 

A typical instance took place in the Ehine Province in 1905. 
An engineer, named VoUmer, had been on three short trips 
with a professional balloonist, and then started from Remscheid 
with an unsuspecting passenger. The weather was perfectly 
clear, and in spite of this they fell into the North Sea and were 
drowned. They attempted to descend too late, as was evident 
from the messages sent by carrier pigeon, wherein they stated 
that the sea first came in sight when they were at a height 
of 10,000 ft. This was clearly a case in which the ascent should 
have been forbidden. But we must not go to extremes, or we 
may find the engineer hoist with his own petard. Thus it was 
clearly an excess of zeal which prompted the Chief of the Berlin 
police to prohibit all ascents in the year 1884 before the 15th of 
August, on the ground that otherwise much damage might be 
done to the crops by the descent of the balloon. Generally 
speaking, since the introduction of the ripping-cord in Germany, 


the number of accidentB has greatly decreased; even in a stiff 
wind the dangers of being dragged and bumped along the ground 
are much smaller if the envelope is suddenly emptied of its gas. 
A landing normally takes place somewhat as follows.^ As soon 
as it is determined to make the descent a suitable spot ia selected, 
partly by consulting the map, and partly by taking account of the 
general lie of the land. When the place has been chosen, a 
rough calculation must be made as to the height at which it is 
best to open the valve. Experience shows that the fall takes 

Flu. U2. — L&nding in a tree. 

place at the rate of 8 or 10 ft. per second ; therefore, if the 
horizontal velocity is known, as also the distance of the point of 
descent, it is easy to fix the level at which the vatve must he 
opened. The rate of falling is about 6 miles an hour, and let 
us suppose that the balloon is travelling at a speed of 12 miles 
an hour, the distance of the spot selected for landing being one 
mile, i.e., 5,260 ft. The height at which the valve must be 
opened will be V'li X 5,280, i.e., 2,640 ft. Shortly before the 
landing place is reached the balloon must be brought to rest by 
means of the guide-rope, ballast being thrown out if necessary. 

" Theory of I.nnrliiig." in the Illmtrierte 


This is a very simple matter if there are no telegraph wires or 
other obstacles. But this seldom happens; there are tiBually 
trees or something of the kind in the way, and then it is neces- 
sary to proceed cautiously, for fear of getting entangled. Ballast 
must be thrown out in order to avoid these obstacles and rise 

Fig. H:l. — Dillingen, soeu tlirough (lie douUs. 
(Pliotofctaph by A. BicJinBtr, of Angab'.inr.) 

above them ; but care must be taken that the balloon does not 
rise too much, otherwise tiiere is a danger of its rising to the 
height from whicli it has fulleii. After leaping over the obstacle, 
the valve must be pulled at once and the balloon brought to the 
ground. Such man(uuvres can he very tedious; sometimes it is 
necessary to jump over houses and villages, which must on no 
account be touched by the guide-rope if there is still sufBcient 



ballast to be able to rise above them. The importance of reserving 
a certain amount of ballast for the end of the journey will now 
be evident. A journey cannot be continued till all the ballast is 
thrown away, leaving none for the purpose of landing ; other- 
wise a guide-rope, rattling along the tops of houses, may be a 
source of great danger to the inhabitants of a village, and quite 
apart from this, the lives of the passengers themselves may be 
exposed ^o serious risks. One cannot too strongly insist on the 
necessity for this precaution ; in fact, the recklessness of the 
man who neglects it is almost criminal. 

As soon as the balloon has been brought by means of the 
guide-rope to a suitable spot for landing, the valve is opened, 
and the basket comes with a heavy bump to the ground. The 
reaction causes the balloon to make a jump, and as it comes 
down again the ripping-cord is pulled as quickly us possible. 
The envelope empties itself almost at once, but a very strong 
wind may occasionally cause the basket to be dragged for some 
little distance along the ground. It is, of course, possible to pull 
the ripping-cord before the balloon touches the ground at all, 
but this must rest in the discretion of the man in charge. 

The following description of a journey undertaken by the 
author may help to illustrate the dangers of the descent. 
I was in charge of all the arrangements, and had as my com- 
panions Dr. Stollberg and Lieutenant George. We started from 
Strassburg in a balloon with a capacity of 70,000 cubic feet, 
and the following is an account of the expedition, written by 
Dr. Stollberg. 

''The balloon seemed to be tugging almost viciously at its 
moorings, when the order was given to let go. At 9.8 a.m. 
we started oflf, with a fairly strong north-west wind behind us. 
At once we threw out ballast, but still remained close to the 
telegraph wires, and it was only after we had lost 4^ sacks 
of ballast that we managed to get clear away. We passed 
away from the ramparts, and were soon far above the housetops, 
even the Cathedral itself seemed far beneath us. In three 
minutes we passed over the railway station, and rose rapidly 
through a thick grey fog. In another three minutes we had 


passed through the clouds with all their damp and cold and were 
now face to face with the sun in all its glory. Towards the east 
was the hump of the Hornisgrinde, and some of the peaks of the 
Eniebis showed through the mist; on the west, parts of the 
Vosges could be faintly seen, looking like dark streaks against 
the horizon. Towards the south was a heavy bank of clouds, 
which looked almost like the snowy Alps ; and right below us on 
the fog was the mysterious shadow of the balloon. But there 
was no feeling of loneliness, although at 9.23 a.m. the reading of 
the barometer was 25'5 in., and of the thermometer 46° P. We 
could clearly hear the rolling of the trains, and the drums and 
bugles at the barracks. All of a sudden the fog disappeared, 
and directly beneath us we saw the railw^ay station. At 
9.37 a.m. the barometer reading was 23'8 in., corresponding 
to an altitude of 6,550 ft. ; the temperature was only 40° F., 
yet the heat from the rays of the sun bothered us not a little. 
The Cathedral looked no bigger than a footstool, with its cross 
at a depth of 5,500 ft. below us. But it seemed so hot that I 
was glad to take ofif some of my winter clothes, and would have 
taken oflf my boots as well, if it hadn't been a little awkward. 
The others experienced the same sensation, and if we bad stayed 
there long we should have been as brown as berries. 

'' However, I had no time to think about these things, and set 
myself down on a sack of ballast to write postcards to my friends. 
In case anybody should be interested in my method, I may as well 
describe it. I order them at the bookseller's, and each card is 
provided with a kind of pigtail, consisting of two yards of 
coloured paper, or better still, of a length of bright 
red ribbon. On the front I write the address and the word 
** J3alloon," and the thing is done. I then throw it over the edge, 
and it amuses me to see the card with its long red tail go tum- 
bling slowly and gracefully down to the ground. On this occasion 
I threw out only two cards, and they both reached their destina- 
tion in due course. At 9.43 a.m. the barometric pressure was 
24*6, the altitude being 5,250 ft. above the sea. We had there- 
fore fallen about 1,300 ft. in six minutes, but we were still higher 
than at 9.23. The Hornisgrinde was our landmark, and seemed 


to be in the same direction ae before ; ne heard the same sounds 
from below, aod concluded that we were still hovering over the 
town. The balloonist is generally descrilied as rushing furiously 
through the air; but this was hardly the case with us; there 
seemed to be something very circumspect about our movements. 
As there was to be nothing to occupy the mind, our thoughts 
gravitated in the direction of caring for the body, and an interval 

ng a ixtiitoon over the lS[in.ij. 

was therefore devoted to refreshment. Suddenly our leader said 
very decidedly that we must land. ^Ve looked at the barometer- 
it was Just before 10 o'clock — and saw that we were already 
descending very rapidly. 1 couldn't understand it; nobody had 
touched the valve rope. Still, the pointer on the aneroid was 
turning round almost as fast as a seconds' hand. Each little 
division on the aneroid meant a full of SO ft. We held out a 
feather at Ihe end of a fishing-rod, but it floated over our heads, 
and our scraps of paper disappeared at once. It was quite 


evident that v/e were going at a breakneck speed to the 

" We threw out some of our precious ballast, but this did no 
good. We came down faster than the sand, and now there were 
only five sacks of ballast left, each weighing 66 lbs. Unfortu- 
tunately there came a cloud between us and the sun ; the 
temperature of the gas in the balloon went down quickly, and 
this further helped us on our downward journey. There would 

Klo. Ho.— Uiidge oicr the lUer, iiear Kempten. 
(Photoj^ph by A. Rledlni^er, Augaburg.) 

have been no danger if we had had a little wind to carry us out 
into the open, but as it was, we could hear from the sounds 
below that we were close to the town and probably directly above 
it. Soon we saw the barracks below us, and came, all at once, 
into the strong breeze in which we had started. I thought we 
should have landed in front of my own house. But we passed 
over the centre of the town, and soon our guide-rope began to 
rattle along the tops of the houses. " Hold tight," said our 
leader; we felt a bump, and found that the rope had knocked a 
ricketty chimney into the street. Soon after this the rope 
managed to coil round the telephone wires, and the only thing to 


do was to cut it ofif. The strain on the rope was tremendous ; 
why it didn't break is a mystery. I thought Lieutenant George 
was a little nearer the rope than I was, so I suggested to him 
that he should lean over the edge and pull it in. We both got 
hold of it after a while, and I brought my trusty knife to bear 
on it. It was lucky I had it with me ; but then I had all my 
wits about me when I started, although I must admit I felt a 
little bustled just now. I had succeeded in cutting half-way 
through it, when there came an overpowering wrench, and it 
vanished over the side of the basket. The jolt was something to 
remember, and we should certainly have been shot out if we 
hadn't held on like grim death. 

" At this critical moment our only policy seemed to be to get rid 
of the rope at any cost. Our chief got on the edge of the basket 
— not a position I should choose at the best of times — and after 
a while succeeded in cutting through the rope at the point I had 
started on. The rope fell down on the roofs of the houses, and 
one end tumbled in the river to the great astonishment of a 
boatman who was close by. We bumped up against one or two 
houses without doing much damage beyond the fact that we 
knocked off a bit of an old chimney, and swept away a few square 
feet of roof. All our ballast was gone, even our maps, our empty 
ballast bags, and the case for holding our instruments. Finally 
we seemed to reach a clear space, and being near enough to the 
ground, we all gave a mighty tug at the ripping cord. We came 
down on the left bank of the river, but the balloon fell unfortu- 
nately with the ripping panel downwards, and so the gas to some 
extent was prevented from escaping. We were dragged a short 
distance along the grass, and ran into a gun-carriage, which 
brought us finally to rest. We pulled the valve open, in order 
to empty the balloon completely, and many willing helpers were 
soon on the spot." 

This account of the journey is sufficient to show that a well- 
constructed basket is capable of withstanding tremendous shocks. 
It is generally possible to escape from the most hazardous positions^ 
and it requires an extraordinary combination of mishaps to bring, 
about such a tragic episode as the death of Sigsfeld at Antwerp. 



The examination of atmospheric phenomena with the help of 
balloons or kites has added considerably to our knowledge of 
the subject. Meteorology has naturally attracted most attention, 
but astronomical work has also been done in the observation of 
eclipses, shooting stars, etc. The balloon has also been used on 
Polar expeditions, but meteorology was undoubtedly the first 
branch of scientific knowledge to which the balloon was usefully 

A Frenchman, named P^rier, discovered in 1647 that the 
barometer stood at a lower level at the top of the Puy de Dome 
than in the vallies. In 1780 Benedict de Saussure made prepara- 
tions for a scientific journey to Mont Blanc, which was carried 
out in 1787.^ In the meantime the inventions of the brothers 
Montgolfier had become generally known, and the results of 
Charles's expeditions had reached scientific circles. On his first 
trip on December 1st, 1783, in the " Charliere," he had taken 
barometric readings, the minimum being 20 in., which corre- 
sponded to an altitude of 11,360 ft. His thermometer also 
showed a reading of 16^ F. 

Saussure recognised at once the importance of the new methods, 
and travelled to Lyons in order to obtain information. He was 
there received on January 15th, 1784, by Joseph Montgolfier 
and Pilatre de Eozier, who were making arrangements for a 
proposed ascent. He took great interest in the theory of balloon- 
ing, and suggested that it might be possible to find favouring 
breezes at diflferent heights, and therefore to move in any desired 
direction. On September 19th of the same year, the effect of 

1 The most comprehensive work on the subject of meteorolojrical ballooning' is a 
book entitled " Wissenschaftliche liUftfahrten,'' by Aswmann ami Berson, publisher.! 
in 18yj> bv F. Viewe*' A: Son, Brunswick. 



the heat of the sun's rays on the temperature of the hydrogen 
in the balloon was carefully noticed by the brothers Robert. 
Lavoisier, who discovered the method of generating hydrogen 
by passing steam over red-hot iron, published in 1784 a com- 
prehensive programme for scientific balloon ascents. The first 
electrical observations were made on June 18th, 1786, by Testu 
Brissy, who ascended into thunderclouds, and said that he drew 
remarkable discharges from the clouds by means of an iron rod, 
carried in the car. A pilot balloon was sent up by the Abb^ 
Bertholon and Saussure, who repeated the observations Franklin 
had made with his kites, proving the existence of atmospheric 

The first ascent, made solely for scientific purposes, was 
undertaken by the American, Dr. Jeffries, of Boston, whose 
adventurous journey across the Channel has already been men- 
tioned. He started on November 80th, 1784, with Blanchard 
from London, and came down in 1^ hours near the Thames 
at Dartford. The attempt to make use of wing-like oars failed 
utterly, but his meteorological observations were of interest. 
A height of 9,000 ft. was reached, and the temperature fell 
to 29° F., whereas in London it was 51°. He took with 
him a Toricelli barometer, a pocket thermometer, a hydrometer, 
an electrometer, and a compass. Besides these things, Cavendish, 
the discoverer of hydrogen, suggested he should take small bottles 
filled with water, in which he should collect samples of the atmo- 
sphere at different heights. His results may be tabulated as 
follows: — 



in inches. 


Altitude in 
feet above 
sea level. 

Rate of 

ascent in feet 

per second. 

liate of change 

of temperature 

per 100 feet. 











The direction of motion above the clouds was determined by 
throwing out a number of cards. The description of the prepara- 
tions that were made for the journey shows that it was done on 



strictly scientific lines with the greatest care, and the results are 
interesting, though no account was taken of the direct effect of 
radiation from the sun, and consequently the temperature values 
are only correct so long as the sky was covered with cloud. 

Jeffries noade a second expedition on January 7th, 1785, which 

haa already been described in some dutail. It maybe noted that 
ou tliia occasion the first triyouometriuiU observations of the 
height of a balloon were mude from the French coast, and the 
allitLide was found to be 4,B00 ft. No barometric readings appear 
to have been taken on the ground level, so that it is not possible 
to deduce much fmm his readings. 

Ilullman, the meteorologi.-t of Berlin, has clearly shown that 



Jeffries was the first to attempt meteorological obeervatiotiB from 
a balloon, though for many years it was eupposed that a man 
named Bobertson was the first scientific balloonist. Hfi made 
an ascent on July 18th, 1803, in the old French military balloon 
" Intr^pide," which had already done duty at the battle of 
Fleurus. The start was made at Hamburg with another man, 
named Lhoest. Bobertson was clearly shown to be an impostor, 
but he gave the following description of his journey in one of 
the Hamburg papers : " We continued to ascend as long as we 
were able to withstand the atmospheric influences. The cold 
was like that of the 
depth of winter ; a kind 
of coma came over us, 
with buzzing in the ears 
and swelling of the veins. 
I made some experi- 
ments with the galvanic 
battery, and noted care- 
fully the flight of the 
birds, as long as it was 
possible to do so. My 
companion complained 
that his bead was swelU 
ing, and I found my own 
bead swollen to such an 
extent that I could not put on my hat, and my eyes were 
bloodshot. We therefore descended. But I noticed the terrified 
aspect of the peasants, and as I had forgotten an important 
experiment, I made up my mind to make another ascent. We 
continued on our way till two o'clock in the afternoon, when we 
came to the ground near Wichtenbeck without any injury to our- 
selves or the balloon. The peasants evidently thought we had 
come from the infernal regions." The results of Bobertson's 
observations have been lost ; but he was either hopelessly incom- 
petentoran impostor, or, very possibly, both. He said he reached 
an altitude of 24,300 ft., that his experiments with frictional elec- 
tricity were a failure, that a galvanic battery only gave five-sixths 

Fio, 147. — Apparatus for generating hydrogen. 


of its normal current, and that the atmospheric electricity was 
positive, as examined by his gold-leal electroscope. Neither did the 
air contain as much oxygen at great heights as it did on the ground 
level. Laplace induced the Acad^mie des Sciences to investigate 
the truth of these assertions ; and consequently 6ay-Lussac and 
Biot undertook an ascent for that purpose, with the result that 
the statements made by Robertson were found to be incorrect. 
They rose to a height of 10,000 ft., and found that the experi- 
ments with frictional electricity worked perfectly; the battery 
continued to give the same current, and the atmospheric charge 
was alternately positive and negative. Gay-Lussac undertook a 
further ascent alone, and reached an altitude of 28,000 ft. He 
found that the percentage of oxygen in the atmosphere was con- 
stant, and independent of the altitude. It was further proved 
that Robertson had only reached a height of 21,400 ft. His 
descriptions of the effect of the reduced pressure on the human 
organism were found to be much exaggerated, but none the less 
it is still commonly believed that at great heights it is not 
unusual for blood to flow from the eyes and ears. This point 
will be dealt with later. 

These expeditions aroused much interest in scientific circles, 
but till 1850 no further work of the kind was done in France. 
In Germany, on the other hand, ascents were made by Professor 
Jungins from Berlin between the years 1805 and 1810 ; he occa- 
sionally reached an altitude of 21,000 ft., but nothing noteworthy 
was done in the way of observations. In the years 1838 and 
1839, the professional aeronaut Green, and the astronomer 
Spencer-Rush made ascents in England, but their results 
appear to be absolutely worthless. Assmann considers that 
the temperatures are too high by at least 36^ F., and their 
altitudes are probably 3,000 ft. too high, so that instead of having 
reached a height of 29,000 ft. they got no further than 26,000 ft. 
Interesting observations were made in America by Wise, who 
has been already mentioned as the inventor of the ripping panel. 
He sent up two balloons in Philadelphia on a calm day. They 
remained close to one another for some length of time ; but one 
eventually rose to a height of 200 ft. above the other, and they 


were then separated. This was owing to the fact that the one 
was carried away by an easterly breeze while the other was still 
being driven in a southerly direction. 

Some ascents were made in France in 1850 by Barral and 
Bixio, who recorded the very unexpected temperature of 39° F., 
at an altitude of 23,000 ft., whereas Gay-Lussac at the same 
height had found a temperature of 10° F. Assmann, how- 
ever, thinks that all the figures are probably correct. There 
is nothing which tends to depress the reading, because it is 
impossible to show a reading lower than the temperature of the 
atmosphere. On the other hand, the radiation from the sun or 
from any other hot body might tend to raise the reading, and 
therefore to show a figure higher than the actual temperature of 
the air. Arago defended the results of Barral and Bixio, because 
he well understood that the direct effect of the radiation of the 
sun must be excluded. Glaisher and Welsh tried to find the 
true temperature by the use of aspirators. Glaisher's results 
were the most important that were in existence till 1887, though 
Assmann showed that there was still considerable doubt as to 
the correctness of the temperatures. French balloonists also 
undertook scientific ascents about this time, but they did nothing 
to improve on Glaisher's results. Among them may be men- 
tioned Gamille Flammarion, the popular astronomical writer; 
Wilfrid de Fonvielle, the brothers Tissandier, Sivel and Croc^- 
Spinelli (who lost their lives at the work), Moret, Dut^-Poitevin, 
Hermite, Besan^on, and many others. It is impossible to do 
more than mention their names, though the importance of their 
work, in some cases at any rate, was undoubted. A member of 
Parliament named Powell made an ascent for meteorological 
purposes, with Captain Templer and Captain Gardner ; but he 
was unfortunately drowned through falling into the sea, while the 
oflBcers barely escaped with their lives.* 

Glaisher made twenty-eight ascents for scientific purposes, and 
was the first to adopt really accurate methods. His plans were 
carried out with the greatest care, and included a wide range of 

1 See Wilfrid de Fonvielle, "Les Grandes Ascensions Maritimes." Paris. 
Auguste Ghio. 1882. 

B 2 


obBflrvations, which were made at short intervals throughout the 
journey. His results are embodied in the reports of the British 
AssociatioD, and included observations from the following points : — 
(1) Determination of the temperature of the atmosphere, and 
of the amount of moisture contained in it at different heights, 
particularly at the higher levels. Determination of the dew- 

Fio. 148.— Qlaisher and Cozwell Id tbe basket. 

point by means of Daniell's wet bulb thermometer, Begnault's 
condensation hygrometer, and of the psychrometer both in its 
ordinary form and with the addition of an aspirator. In the 
case of the latter, large quantities of air were to be passed 
through the vesaels containing the thermometers at different 
levels, more especially the higher levels ; special attention to 
be directed to the highest levels which are suitable for human 
habitation, with special reference to the mountains and plateaux 



of India. At these heights the readings of the psychrometer to 
be carefully compared with thoee of Daniell's and Begnault's 

(2) Comparison of the readings of an aneroid with a mercury 
barometer up to heights of 5 miles. 

(3) Determination of the electrical properties of the 

(4) Determination of the properties of the oxygen in the 
atmosphere by means of ozone paper. 

(5) Determination of the period of oscillation of a magnet at 
the gronnd level and at different altitudes. 

(6) Collection of samples of air at different levels. 

(7) Notes on the height and 
constitution of the clouds, their 
density and depth. 

(8) Determination of the 
velocity and direction of the 

in so far as this is 


>. 149.— alaiBher'B inatronieDU. 

(0) Acoustical observations. 

(10) Any general atmo- 
spherio observations, not included under the foregoing heads. 

Anybody who has ever made a meteorological ascent will well 
understand the amount of work involved by the numerous obser- 
vations, and the careful method which would be necessary to cover 
so vast a range. It has been shown that on a journey made on 
July 21st, 1863, Glaisher must have made in a space of GO seconds 
seven readings of the aneroid, accurate to the hundredth of an inch, 
and 12 readings of the thermometer, accurate to the tenth of a 
degree. On June 26th, 1863, he carried out the following observa* 
tions in 1 hour 26 minutes, viz.: 107 readings of the mercury 
barometer, & similar number of the thermometer attached to the 
barometer, 63 readings of the aneroid, 94 of the dry, 86 of the wet 
bulb thermometer, 62 of the gridiron, 13 of the dry and 12 of the 
wet bulb thermometer fitted with aspirator, besides several obser- 
vations with the hydrometer, and noting the time on 165 different 
occasions. Each observation must therefore have taken on an 


average 9*6 seconds, including such necessary attention as was 
given to the adjusting of the various instruments and apparatus.^ 
At first these instruments were mounted on a bench placed in the 
middle of the basket, with its ends projecting over the edge ; but 
in the later expeditions this was altered and the bench was 
placed on the edge of the basket, so as to prevent, as far as 
possible, any effect of radiation from the observers themselves. 

It has been already stated that the influence of the radiation 
of the sun on the temperature readings was well known. GsLy- 
Lussac and Biot first noticed it owing to the burning sensation 
produced on the skin; they tried to protect the thermometer 
from the effects of the sun by enclosing it in a pocket handker- 
chief, an arrangement which was wholly insufficient. Arago 
proposed to determine the temperature by means of a thermo- 
meter suspended by a string, which would be dashed about by the 
air, and consequently continually brought into contact with fresh 
volumes of air- In this way an approximately correct reading 
could be obtained. Welsh used an aspirator in connection with 
his thermometer, not with a view to neutralising the effect of the 
sun's radiation but in order to be able to detect any variation of 
the temperature as soon as possible. His work was done close to 
the sea, and it was therefore impossible to undertake any very 
lengthy expedition. Assmann has, however, shown that even 
this type of instrument does not give reliable results, though 
Welsh's work was unknown to him when he devised his well- 
known aspirator-psychrometer, which forms an indispensable 
item in the outfit of the scientific balloonist. 

This instrument contains two thermometers, having their 
mercury bulbs protected by highly polished metal tubes, about 
half an inch in diameter. These tubes are open at the top, and 
communicate at the bottom with a central metallic tube, about 
one inch in diameter and 8 inches long. At the top of the instru- 
ment there is placed a clockwork apparatus, driven by a spring, 
which serves to put two metal discs in rotation. The rotation of 
these discs sucks the air through the central tube, and con- 
sequently past the thermometer bulbs, at a speed of 8 or 10 ft. per 

1 See Assmann's " Wissenschaftliche LuftfahrtcD," vol. i., page 56. 


second. The rays of the snn Bie reflected b; the polished metal 
surrounding the bulbs of the thermometers, which are therefore 
protected from external influences and register the temperature 
of the air as it is sucked past them. In this way the true 

vith instrumeiiU according to the method propoicd 

by Assmann. 

temperature of the atmosphere can be found, supposing that the 
thermometers are kept at a sufficient distance from the observers, 
etc., to be free from any of the effects of radiation that may be 
due to the contents of the basket. The instrument is preferably 
mounted on [some kind of support which keeps it at a suitable 
distance from the basket on the outside. It is then quickly 



drawn up to the edge of the basket for the purpose of taking 
a reading ; or, if very great accuracy is needed, it may be read 
through a telescope. The working of this instrument has been 
tested by long exposure to the rays of the sun on the top of the 
Santis, and its readings were found to be very accurate. 

Professor Assmann proposed to Professors Berson and Siiring 
that they should make an ascent in a balloon, and compare the 
readings obtained by Glaisher's methods with those obtained by 
means of the aspirator-psychrometer. It 
was found that the readings given by the 
latter were considerably lower than 
Glaisher's figures, the difference amount- 
ing on an average to 27° F. It therefore 
seemed likely that Glaisher's results 
were to some extent vitiated by his 
defective apparatus. Assmann examined 
Glaisher's work very carefully, and deter- 
mined that the best way of doing this 
would be to make some fresh ascents. 
In the years 1884 and 1885 some ascents 
had been made by a man named Jeserich, 
who had principally confined his atten- 
tion to taking samples of the air for 
chemical analysis, though he also made 
some electrical and meteorological obser- 
vations. After this the officers of the 
Prussian Balloon Corps made scientific 
observations. This was due in the first instance to Captain 
Buchholz, who entered into communication with the Meteorological 
Institute, and arranged that Lieutenants von Tschudi, von Hagen, 
and Moedebeck should undertake meteorological observations. At 
a later date, work was done by Major Gross, who pointed out the 
effect produced by the radiation from the sun on a thermometer, 
and recommended the use of the Assmann instrument. This was 
first done by Assmann and Sigsfeld on the occasion of an ascent 
in a captive balloon at Berlin in May, 1887, and Moedebeck was the 
first to use it in a free balloon on June 23rd of that year. Soon 

ir-psy chrome tcr. 


afterwards Sigsfeld made a large balloon, named the "Herder," 
and went up in it on June 23rd, 1666, in company with Kremser 
of the Meteorological Institute. Assmann's instrument was used 
on this occasion, but still the results were not wholly satisfactory, 
and it was necessary to have recourse to the subscription list. 

Fio. 152, — Professor Axsmann and I'roteasor Hereon, 
Help was speedily forthcoming from various quarters, and the 
" Herder " was soon followed by the" M. W." and the "Meteor." 
In the latter Assmann made five successful ascents in company 
with Gross, KilUsch, Berson, and others. Assmann was indefatig- 
able in the matter of raising money ; he clearly saw that general 
conclusions could only be drawn from a long series of observa- 
tions taken under all sorts of different conditions. The Kaiser 
placed the sum of £2,500 at his disposal, and money was also 


obtained from other quarters. The balloon '' Humboldt " was 
then built, and started its career under an evil omen. At the 
first descent Assmann broke his leg ; on the second journey the 
balloon settled down on a lightning conductor; on the third 
something went wrong with the valve at a height of 10,000 ft., and 
Gross and Berson sustained rather serious bruises from the 
bumping of the basket on the ground ; and finally, on the sixth 
journey the whole thing exploded when it came to earth through 
the gas in the balloon coming in contact with an electric spark. 

It seemed very doubtful whether the work could be continued, 
until the Kaiser again subscribed £1,600. The *' Phoenix " was 
then built, and in it Berson reached the greatest height on 
record, viz., 80,000 ft. Twenty-two journeys were made in this 
balloon altogether, and the results obtained were of great import- 
ance. Others were also pressed into the service. Mr. Patrick 
Y. Alexander lent his balloon, the ** Majestic," which had a 
capacity of 106,000 cubic feet and was made of varnished silk. 
The Balloon Corps did its part, and took meteorological observers 
on many of its trips. Forty-six ascents were made with the 
funds that had been raised. The results were so encouraging 
that the Kaiser placed a further sum of £1,000 at the disposal of 
Professor Assmann, and also showed his interest in the work by 
attending some of the ascents in company with the Kaiserin and 
his sons. 

On working out the results, Assmann noticed that Glaisher's 
results showed that the temperature in England at certain 
heights was greater than that in Germany, and that this difference 
increased with the height. At a height of 8,200 ft. the difference 
appeared to be 2*5° F., whereas in one case at 26,000 ft. it 
appeared to be no less than 37'2° F. Consequently it must 
either be warmer over England than on the Continent, or on the 
other hand, there mi^ht be something wrong about the figures. 
Welsh had found lower temperatures in England, and in any 
case there was some doubt about Glaisher's figures. On Sep- 
tember 5th, 1862, he had made an ascent, and became unconscious 
at a height of 26,000 ft. He stated, however, that he had actually 
reached an altitude of 87,000 ft., and this figure was calculated 


in the following way. At an altitude of 29,000 ft. be was rising 
at the rate of 16 ft. per second, and in thirteen minutes, when 
he regained conscioustieas, he found that the balloon was falling 
at the rate of US ft. per second. Therefore he calculated that he 
must have risen to a height of 37,000 ft., while his minimum 
thermometer registered 12"l° F. Coxwell, who was also 
in the balloon, succeeded in gripping the valve-rope with his 
teeth and let out some of the gas. He said that the pointer on 

^ ^ 


— The Kaiser attending the ascent of a recording balloon o 
Teropdhofer Feld, near Berlin. 

I the 

the aneroid coincided in position with a string fastened across 
the basket, and that this was found to denote a reading of 7 in., 
corresponding to an altitude of 87,000 ft. It has been pointed out 
by Assmann that observations mode under conditions bordering 
on unconsciousness are very liable to error. It is known that a 
balloon falls with a maximum speed of 16 ft. per second.' But 
Glaisher's figures point to a fall at the rate of 130 ft. per second, 

' During the Bumnier of 1S02 a descent was made by the author in companj' 
with Professor Miethe ; the readings of the barometer certainly the weif a maiiniuin 
cpceil of more than 3.S ft. jicr second. But a thunderstorm wa» raging at the time, 
and the strong downward wind increased the speed of falling. 



and if it bad actually fallen at anything like that rate it would 
donbtlesB have been torn to pieces. The apparent errors in 
Glaisber's results are doubtless due to the effects of solar 

It was evident that a number of important problems could not 
be solved by ascents from a single spot, and that it would be 
necessary to organise ascents from many places, and, if possible, 
to establish observatories for the purpose. It was further 

— Capti 


Via. 154.— Major Moedebecli. 

desirable to make simultaneous ascents from a number of places 
with a view to mapping out the state of the atmosphere after 
the manner adopted in the meteorological reports published 
from day to day. This has given rise to an international 
organisation for the purpose of making such ascents, which 
mostly take place on the first Thursday in every month. G-aston 
Tissandier started the idea, and on July 14th, 1693, simultaneous 
ascents were made from Berlin and Stockholm. On August 4th, 
1694, ascents were made from Berlin, Goteborg, and St. Peters- 
burg. Later tests on these lines were undertaken by an 


international organisation consisting of Botch, the director of the 
Blue Hill Observatory in America ; Besan^on, de Fonvielle, 
Hermite, and Teisserenc de Bort in France ; Assmann, Erk, 
Hergesell, Moedeheck and the Balloon Corps in Germany ; Mr. 
Patrick Y. Alexander in England; Colonel von Kowanko, Colonel 
PormortzefF, and General Rykatsoheff in Bussia, and Andree in 

A conference for meteorological purposes met at Paris in 
September, 1896, and an international commission for scientific 
ballooning was then inaugarated, under the presidency of Dr. 
Hergesell, the director of the 
Meteorological Institate for Alsace 
and Lorraine. Most civilised 
countries are nov represented at 
the conferences which take place 
every two years, and meetings have 
been held in Strassbarg, Paris, 
Berlin, St. Peterburg, and Milan. 
It is perhaps difficult for an out- 
sider to anderstond the many-sided 
activity of the balloonist in this 
field of research, and to form an 
idea of the problems that are await- 
ing solution. It may therefore 
be as well to quote a portion of the speech made by Dr. 
Hergesell when he opened the conference at Berlin in his 
capacity of president. " Our first task consists not in carry- 
ing out the largest possible number of simultaneous ascents, 
either with or without observers in the car, but in organising 
the basis of co-operation by the employment of accurate instru- 
ments, which are constructed on similar principles. The out- 
lines of such arrangements as are possible to secure the use of 
similar instruments were discussed at our first conference at 
Strassburg. Since that time, such balloons as carry observers 
have been fitted with the aspirator-psychrometer devised by 
Assmann and Sigsfeld; and balloons without observers have 
carried the recording instruments due to the indefatigable industry 

15S.— CapTAm QroBs. 


of Teisserenc de Bort. The recording balloon has become a 
moat useful auxiliary, and has brought us most surprising 
results oat of the icy regions at a height of twelve miles above 
our beads. Berson and Siiring rose to heights of six miles, and 
in so far as their records go they confirm the results obtained. 
Since the month 
of November, 1900, 
simultsoeouB as- 
cents are made on 
the first Thursday 
in the month at 
Paris, Strassburg, 
Munich, Berlin, 
Vienna, St. Peters- 
burg, and Moscow ; 
and on May 5 th, 
1902, the 213th 
recording balloon 
was sent up. 

" The seed thus 
sown has borne 
good fruit. It had 
generally been be- 
lieved that Glai- 
sher's results were 
correct, and that 
at fairly low levels 
the temperature 
Fifl. 157.— A recording balloon with instruments. remained constant 

throughout the year. But this has been shown to be altogether 
wrong. There is eternal change even at great heights, and the 
temperature varies just as much at levels of 30,000 ft. as at 
1,200 ft. Moreover, at the same heights above Paris and St. 
Petersburg there may be difTerences of temperature amounting 
to 60" or 70^ F. Our observations have also proved that the 
variation of temperature is not continuous, but that the atmo- 
sphere is composed of layers, as it were, which often show 


considerable differences of temperature. This layer-formation 
is one o( the most important subjects at present under 

" The future has still mach vork to do. At present, systematic 
observations are made in few parts of the earth, and sucb portions 
of our own continent as Italy, Spain and Norway are unrepre- 
sented at our conference. We are proposing to cover the ocean 

by means of balloons sent up from 

steamers, and oar work must also be 
extended to the tropica. In this province 
the assistance of England is very im- 
portant, seeing that India offers great 
scope for these observations. Our aim 
must be to explore the great unknown 
above our heads, and to discover from 
it the secret of the weather chart." 

Since this speech was mode, some of 
its hopes have been fulfilled ; Italy, 
Spain, and Sweden have joined the con- 
ference, and much work has been done 
by sea as well as by land. 

We must now describe methods by 
which meteorological instruments can be 
sent on a joomey in the air. The oldest 
method is the kite. In 1749 Wilson 
used it to seud up thermometers for the 
measarement of temperatures ; in 188S Professor Douglas 
Archibald used it for finding the velocity of the wind ; and since 
1894 the American observer Rotch has used it largely for the 
work of his observatory. It was due lo the success of Eotch's 
work that the kite has since been used almost everywhere for the 
purpose of atmospheric observation. Teisserenc de Bort has 
followed Botch's example ; he has made excellent arrangements 
for sending up kites and balloons at Trappes near Paris, and this 
has been done at his own expense and with Uttle help from out- 
side. Professor Hergesell tried to induce the provincial authori- 
ties to provide him with funds; hut there happened to be no 

Fio. 15S. — A wickerwork 
basket witb instrumenU 
for a recording balloon. 



available BurpluB in the exchequer. Still kite ascents have been 
regularly made for these purposes id Strassburg since 1896. 
Professor Assmann succeeded in erecting an observatory on a 
large scale, and started on this work as soon as the sum of 
£2,000 had been voted for the purpose. The building began 
on April 1st, 1899, and on October iBt of the same year it was 
possible to make the first ascents vith kites and balloons. A 
site was chosen at Tegel in the north of Berlin, because the 
Balloon Corps was stationed there, and their help was thought 
likely to be useful, seeing that the preparation of the gas and 
the inflation of the balloon would 
be a difficult matter for the limited 
staff of the observatory. More- 
over, the Balloon Corps might, on 
the other hand, derive consider- 
able advantages from association 
with scientific work. The observa- 
tory contained a carpenter's shop 
for making kites, a balloon shed, 
a house from which the winches 
were worked, with a tower 90 ft. 
high, and also the necessary work- 
ing and living rooms. Assmann 
saw that kites would not be 
Fio. 159.— Dr. Hergeaeii. Sufficient for the carrying out of 

his plana ; he intended to take observations at great heights 
every morning for several hours, and therefore ordered a kite- 
balloon, which was to be used when the velocity of the wind was 
leas than 18 or '^0 ft. per second, a speed insufficient for the flying 
of kites. Ordinarily either kites or the kite-balloon are used ; 
but on "international" days free balloons are sent up, either 
with or without observers. The latter are used in a special 
manner that has been gradually evolved as the result of 

The use of balloons without observers but carrying recording 
instruments was the idea of Hermite and Besan^on, and the 
details were carefully elaborated by Teisserenc de Bort in his 



" Observatoire de la MetSorologie dynamique." BallooQS are 
used, made of the lightest aJlk, cambric or paper, varniBhed with 
rubber solution or linseed oil ; their capacities vary from 1,000 
to 17,500 cubic feet. The weight of the instruments is vary 
small, and therefore the size of the balloon depends generally 
on the height to which it is proposed to ascend. The net is of 

very light construction ; it has merely to resist the internal 
pressure and carry the basket containing the instruments. 
Assmann has designed an arrangement whereby an alarum 
clock opens the valve after a certain time, and therefore 
causes the balloon to descend after it has reached a certain 
height. In order to prevent the effects of solar radiation, the 
balloon must be prevented from hovering in one position, so that 
the thermometers are continually brought into contact with fresh 



volumes of air, in a manner similar to that Adopted in the 
aspirator-paychrometer. If the balloon is made to rise quickly 
and then to fall at once, the thermometers give correct values ; 
but if it is allowed to drift gently along, exposed to the raya of 
the sun, the readings will be too high. Attempts have been 
made to shield the instruments by placing tbem in a wicker 
basket, covered with highly pohshed silver or nickel paper, but 

Fig, lUl. — Ascent of a boi.kite containing melcorologicn 
(rhotot-i»|>1> by tlis B«r1iner IllustntlonssesBllscbull.) 

this is not sufficient. Kites have been sent up in the early 
morning before sunrise, and figures, obtained in this way, have 
been compared with those recorded in bright sunlight. But the 
da3'light ascents are much the more important, as the effect of 
the sun on the atmosphere must on no account be neglected. 
Assmann has also invented a system by which rubber balloons 
with diameters of one or two yards are sent up, gradually 
expanding ns they rise, till they finiilly burst ; a linen cap acta 
as a parachute, and the case with the instruments falls gently to 
the ground. Such balloons will remain in the air from one to 


three hours, and give good results. They are now employed in 
most observatories. 

It is of course important th&t the balloons and instruments 
Hhoulil be returned to the observatory as soon as possible. This 
matter was thoroughly discussed at the conference at St. Peters- 
burg, and it was suggested that bells should be mounted on the 
balloon, so as to attract attention. Hitherto the loss has 
amounted to something in the neighbourhood of 4 per cent. 
If the balloons fall into water the instruments are naturally 
lost, unless Hergesell's plan is adopted of attaching floats and 


Flo. 1B2.— Winch house at ABsraann's aeronaulical obsciTstory. 

drawing attention to the spot by means of a second pilot 
balloon. If they fall into a wood they are generally found, 
sooner or later. 

There is a general impression that ascents with kites are much 
cheaper than those with balloons, but this is not the case. Any- 
one who has done practical work with kites will know that they 
are cheaper in the first instance, but the cost of maintenance is 
greater, A kite is often smashed to pieces by the wind, and the 
instruments are either destroyed or rendered more or less useless. 
Even if great care is taken, the wire holding the kite may be 
broken, and several miles are either lost or unfit for further use. 
Consequently the coat of maintenance is so great that kites are 


not less expensive for this form of work than balloons. The 
ascent of a kite is often a matter of some difficulty, and it is 
only by the exercise of the greatest cave that accidents of one 
kind or another can be avoided. It is therefore a wonderful feat 
on the part of Assmann to have succeeded every day for the last 
four years in making an ascent either with kite or balloon. Tlie 
ascents are made with the help of an electrically-driven winch, 
and there are means of telling the pull on the wire. The winch 
is used to pull the kite down, and also sometimes to help it to 
start. Suppose the wind to be very light. A considerable length 
of wire, amounting perhaps to 500 or 1,000 yards, is laid along 
the ground ; the kite is held in the air, and the winch is started 
at full speed. In this way, the necessary air-resistance is 
created, and it gradually rises to an altitude where the breeze 
is blowing more strongly. The breakage of a long wire may be 
very dangerous in the neighbourhood of towns. It may fall 
across telegraph or telephone wires, and still more serious acci- 
dents have arisen from its coming in contact with the overhead 
tramway conductor. At Tegel it often happened that the kite 
got carried away by an overhead breeze, blowing in a different 
direction from the ground breeze, and its wire became entangled 
with the ropes holding the military captive balloon. Mishaps of 
various kinds induced Assmann to move his observatory from 
Tegel to Lindenberg, which is at a distance of 40 miles to the 
south-east of Berlin. The winch-house is here arranged at the 
top of a small hill, and is capable of being rotated so that it can 
follow the flight of the kite in any direction. Naturally enough, 
the experience of the four years at Tegel was very valuable, and 
consequent improvements in the arrangements at Lindenberg 
were therefore made. Assmann has two assistants in the 
scientific department, and two others who render technical 
assistance. The whole of the staff, including helpers of one 
kind and another, consists of 18 persons, and together with 
their wives and families they constitute a little colony of 50 
persons. On October 1st, 1906, Assmann had accomplished the 
feat of making ascents on 1,379 consecutive days ; but with the 
means at his disposal it is impossible to make ascents both by 



day and by nif>ht without iiitermiBsion. In the neighbourhood 
of Lindesberg is a eniall lake, called the Scharmutzelsee, about 7 
miles long ; and this seems likely to be useful for kite ascents 

Fia. 1<>3. — Cnrrea taken bj recording iiistru meats. 

In tba lower h«lt thn ■'nrrea an Riirkrd byx pointnon ■ plecr of paper that hae been c«l«d with 
loat. These cutk-u an nhowu dear])' In the upper half of the illmlmtloa. 

It is intended to use a motor-boat for the purpose of starting the 
flight. The Kaiser has taken great interest in scienti&c balloon- 
ing, and was present at the inauguration of the new observatory, 
together with the Prince of Monaco and other well-known 


The greatest height reached by a bnlloon with recording 
instruments was 85,000 ft. ; and this took place at Btrassburg 
on August 3rd, 1905. The highest ascent with a kite was made 
from Lindenberg on November 25th, 1905, when an altitude of 
21,100 ft. was reached. The height which a balloon will reach 
under these conditions depends of course entirely on the 
quality of the materials. It is possible that some little time will 

FlO. I6i. — Curtea givtn bj recording ii 

elapse before ascents will be made over the surface of the Schar- 
mutzelsee, and it will therefore be well to consider what has 
already been done by way of carrying out observations above the 
surface of lakes and seas. 

The greater part of the earth's surface is covered with water, 
and the exploration of the atmosphere that lies over the sea ia 
an absolute necessity if any progress is to be made towards the 
discovery of general laws. Rotuh first pointed this out, and sent 
up balloons with recording instruments over the sea. In the 
spring of 11)00, Professor Hergesell sent up a kite by means of a 
motor-boat over the Rodensee, and £oon the number of observers 



increa8ed. Rotch and TeisBerenc de Bort croHBed the Atlantic, 
BerBon and Klias went to the North Cape, and Hergesell made 
an expedition with the Prince of Monaco in the Mediterranean 
and Atlantic. IlergeBell haa lately started an observatory for 
the purpose of studying the air over the Bodensee, and a motor- 
boat has been constructed for starting the kites. 

The results of the observations of Hergesell and the Prince of 
Monaco are very interesting, as are also those of liotch and 
Teisserenc de Bort. It is here only possible to give a general 
outline of their results.^ With kites Hergesell reached altitudes 
of 20,000 ft., and with balloons of 47,000 ft. ; and he concludes 
that above the Atlantic, which he crossed in the yacht Princess 
Alice, belonging to the Prince of Monaco, there are three atmo- 
spheric layers. The lowest of these has adiabatic temperature 
gradients, with a decrease of 1? V. per rise of 180 ft., and con- 
tains much moisture. The middle layer is very dry, and shows 
no decrease of temperature, but rather, on the other hand, a 
slight increase. The uppermost layer has a very decided 
temperature gradient in a downward direction, and contains 
little moisture. This last layer reaches to a height of 80,000 ft., 
at which level Teisserenc de Bort and Assmann have found 
that the air tends to become warmer over the mainland. 

An interesting investigation related to the question of the 
trade winds. In consequence of the revolution of the earth on 
its axis, the trade wind blows from the north-east in the northern 
hemisphere, while in the southern half it appears as a south-east 
wind. Between the two comes the belt of calm. Seeing that 
the trade winds blow from the poles, it seems reasonable to 
suppose that at higher levels we should find winds blowing in the 
opposite direction towards the poles. But it now seems thai 
this view is likely to be incorrect, though it is said that the 
smoke from the volcano Pic de Teyde on Teneriffe blows from 
the south-east after it has reached a certain height. Hergesell 
examined the zone lying between 20' and 88' northern latitude 

* Fuller particular are to be found in the *' AnnaU of the Anlronomical ObHcrra- 
tory of Harvard ('olle^^e," vol. 43, part 3, which wmtainn the re»ultH of Kotch's 
cxpeditioiiH ; aUo in *• Bcitriij^e zur I'hynik der freien AtmoMphilre,'* VJOi and 1005 ; 
and in the MetrorolwjiKrhv Zritsrhri/tf November. liHio, 


and between 10° and 42° longitude west of Greenwich up to 
levels of 47,000 ft., and found that the wind mostly blew from 
the north ; only on one day at a height of 6,000 ft. it appeared 
to blow from the south. Teiaserenc de Bort and Rotcb did 
their work elightly to the north of the Canaries, near the Azores ; 
they found, like Hergesell, winds blowing from the north-east 
and east at the lower levels, and at greater heights it blew 
from the west and south-west. This work promises interest- 
ing results, but it does not appear to be quite so simple as was 
y--'^ '^-v^ It may be interesting to de- 

/ ^^t^^^^^^ scribe the sensations of the human 

/ ^^^^k ^^n body at these high levels. An 

/ ^^^^H^Vk^^Ey account of a journey undertaken 
/ ^^^^C^k ^^V\ by Count Zambeccari at Bologna, 

/ ^^^^^^Bli^^Fvl ^'^ l^S, is still in esistence. He 

^^^^^r^^H j made an ascent with two friends 
1 ^^^^^^Pj^^B I a Charlilre, which was to be 

\^^^^^^^m_^^^K^l heated with a big spirit lamp. 
^^^^^^^^^^^^^^/ The balloon had so much lift that 
^^^^^^^^^^^^^r Zambeccari and one com- 

^^^^^^^^^^^m panionssoon became unconscious, 

^^^^^^^^^^F while the other, who had not done 

^^^^^^ BO much hard work on the pre- 

parations before startmg, ^as 
quite unaffected, and succeeded in waking them as they were on 
the point of falling into the sea. Before they had succeeded in 
throwing out any of the ballast they found themselves in the 
water, and then proceeded to throw overboard everything on 
which they could lay bands, including instruments, clothing, 
lamps, propellers, ropes, etc. The balloon at once rose to a great 
height, reaching a higher level than that from which it had 
previously fallen. Breathing became very difficult; one became 
seasick, another bad bleeding at the nose, and in consequence 
of ihe severe cold all their wet clothes were covered with ice. 
The balloon soon descended again, and once more fell into the 
sea, the aeronauts being rescued as they were on the point of 


drowoing. Several of Zambeccari's fingers were so frostbitten 
that they had to be cut oS. 

Gl&isher and Coxwell made a remarkable ascent in Sep- 
tember, 1862. The baltoon had so much lift that at the end 
of 18 minutes it was 10,600 ft. high, having risen at the rate 
of 10 ft. per second. At this height the temperature was at the 
freezing point. At 16,000 tt. Coxwell began to lapse into a 
comatose state, whereas Glaisher was unaffected. They soon 

reached an altitude of 29,000 It., where the thermometer regis- 
tered 2° F. The sensations they experienced have been well 
described by Glaisher in the following words : — 

" Up to this moment I had been able to take my observa- 
tions without being inconvenienced by any breathing troubles, 
whereas Coxwell had often lapsed into unconsciousness. But 
I soon found that I was no longer able to see the mercury 
column of the wet-bulb thermometer, and after a while the 
same thing happened with the hands on the clock and the fine 
marks of division on the instruments. I therefore asked Coxwell 
to help me, as I could no longer see to do the work. But the 
balloon had been in a constant state of rotation, so that the 



ropea connected to the valve had become entangled ; Coxwell 
therefore climbed up from the basket and managed to free them. 
I made another reading, and noticed that the barometer reading 
was 9'71 in., which denoted a height of 29,000 ft, I placed my 
right arm on the benclt; and when I tried to move it again, I 
found that it hung from my side in a paralysed state, I then 
tried to use the other arm, but it was also helpless. I roused 
myself as far as I could, and tried to lean over to read the 
barometer; but I found that I had lost the use of my limbs, 
and my head fell on my left shoulder. I made another attempt 

Flu. 167. — Iteconling balloous on tlie as. Plawt. 

to regain the use of my limbs, but it was impossible to move my 
arms. I was indeed able for a moment to raise my head, but 
it sank again on my shoulder. I fell with my back against the 
side of the basket, and my head rested on the edge. My arms 
and legs seemed to have lost all their strength, but my spine 
and neck seemed capable of some movement with a very great 
effort. But this did not last long, and I was soon entirely 
incapable of making any movement whatever. I saw Coiwell 
sitting in the ring, and tried to talk to him, but did not succeed. 
Then everything suddenly appeared dark ; the nerves of my 
eyes refused to work, but I had by no means lost consciousness. 
I was in fact jusl as clear in the head as I am at the moment 
of writing this. But it was perfectly evident that death was 


staring me in the face unless we descended at once. Suddenly 
I lost consciousness. I cannot say what the effect of all this 
was on my hearing, seeing that there were no sounds to be heard ; 
we were at a height of 36,000 ft., where it would be impossible 
for any soundB to reach us from the earth. 

" At 1.54 I had made my last observation, and assuming that 
two or three minutes had elapsed in the interval, it would now 
be 1.57. Suddenly I heard Coxwell pronounce the two words 
' temperature ' and ' observation ' ; this was a sign that I 
had recovered consciousness, and was able to hear. But I could 

neither see him nor speak to him, nor could I make any move- 
ment. Again I heard Coxwell say to me, ' Try to do it.' I 
Baw the instruments very indistinctly, but all at once everything 
became quite clear. I said that I had been unconscious, and 
Goxwell said be bad nearly been eo, too. He showed me his 
hands, which had been quite paralysed and looked black. He 
said that while he had been sitting on the ring be had been 
overcome by the cold, and had slid down on his elbows into the 
basket, as he was unable to use liis hands. When he saw that 
I was unconscious, he seized the valve-rope with bis teeth, 
thereby opening the valve. I resumed my observations at 
2.7 p.m." 


Glaifiher's report contains no further reference to his bodily 
sensations on this journey, and after landing he suffered no 
further discomfort. He estimated the maximum height at 
86,000 ft., but, as already stated, Assmann considers that it 
did not exceed 29,500 ft. In any case, the journey was a very- 
remarkable performance ; no human being has penetrated to 
such heights either before or since without taking a supply 
of oxygen. Glaisher's account gives us a good idea of the 
condition of the human organism under such circumstances. 
This led the way to experiments with animals in order to find 
how they behaved in a more rarefied atmosphere, and how their 
condition improved if they were supplied with pure oxygen. 
Paul Bert carried out some experiments with small birds, which 
were placed on the receiver of an air-pump. He showed that 
all the symptoms disappeared as soon as the animal was supplied 
with oxygen, and therefore constructed a large airtight chamber 
in order to continue his experiments with human beings. These 
observations gave the same result. It was found that the quick 
breathing with rapid pulse, the buzzing in the ears, the fainting 
fits and mental exhaustion, ceased at once as soon as oxygen 
was supplied. 

In March, 1874, two Frenchmen, named Sivel and Croc6- 
Spinelli, made an ascent in order to try the effects of breathing 
oxygen at great heights. They then found that whereas in the 
vacuum chamber they could very well stand a pressure as low 
as 13 in. of mercury, the same pressure in a balloon caused very 
great discomfort. They ascribed this to the temperature, which 
was very low, the thermometer reading only 11° F. The 
inhaling of oxygen produced under these conditions very great 
relief. They continued their experiments, but unfortunately 
with fatal results. On April 15th, 1875, Gaston Tissandier, 
Sivel and Croce-Spinelli made an ascent with the intention of 
reaching still greater heights than Glaisher had done. They 
therefore took with them small balloons, which contained a 
mixture of oxygen and air. These balloons were fitted with 
tubes, through which the gas might be inhaled as occasion 
required. Sivel was the first to be attacked by a fainting fit, 


which, however, quickly passed off. Tissandier meanwhile 
continued meteorological and physiological observations without 
interruption. His pulse mode 110 beats in the minute at a 
height of 13,C00 ft., while it made 80 under normal conditions ; 
at 17,sOO ft. Sivel's pulse was beating at the rate of IdO per 
minute, and Groce's at 120, and the rate of breathing increased 
in much the same proportion. At 23,000 ft. their strength 

Fig. 169.— Baro-thermo-hygrograpb, designed for balloons with ohservere 
bj Dr. Hergesell, and made bj Bosch, o( Straubarg. 

began to fail, and they fell into the usual listless condition. 
Their hands became stiff from the severe cold, and they were 
attacked by giddiness and fainting fits. Sivel and Groce sat 
motionless on the bottom of the basket, but Tissandier was able 
to see from the barometer that they had reached a height of 
26,000 ft., and then also became unconscious. After some time 
he was aroused by Croce, who suggested that some ballast should 
be thrown out, as the balloon was falling rapidly. But Croc6 
had to do it himself, as Tissandier again lost consciousness. 



After a while Tissandier recovered his senses, but he was unable 
to arouse his companions, who had been suffocated in the mean- 
time. He managed to land after being dragged heavily along 
the ground for some distance. Sivel and Croce had been 
suffocated at a height of 27,000 ft., owing to the fact that they 
no longer had the power of inhaling the oxygen. 

In Germany, expeditions to great heights have been made by 
Herr Berson, Dr. Siiring, and Captain Gross. A few particolars 
may be of interest. The first ascent of any importance was 
made in the "Humboldt" on March 14ih, 1893. The valve 

opened unintentionally at a height of 10,000 ft,, while on the 
descent, and the balloon fell to the ground in 10 minutes. 
Gross and Berson had proposed to rise to the greatest height 
possible, without the use of oxygen. Pulse and breathing began 
to be hurried at a height of 16,000 ft. Even the slightest exer- 
tion was found to be an effort, and to be accompanied by very 
decided beats of the heart. At a height of 20,000 ft. they were 
unable any longer to do their work, and the lifting of the heavy 
sacks of ballast became an impossibility. The stomach is unable 
to take food under these conditions, but a sip of wine or brandy 
acts as a restorative, thou<!h this effect soon dies away. In spite 
of their rapid fall the balloonists sustained no serious injuries. 
Captain Gross was slightly injured in the ribs ; otherwise they 



only Buffered from bruises, and, after resting a few days, were 
able to return to Berlin. 

The ascent of December 4th, 1894, ought also to be mentioned, 
because Berson then reached an altitude of 30,000 ft. Tlie 
balloon "Phcenix" was used on this occasion. It had a capacity 
of 92,000 cubic feet, and was filled with hydrogen at Strasshurg, 
Berson made tlie ascent alone, and took witli him a cylinder 
containing 36 culiie feet of oxygen. In order to reduce the work 
to a minimum, the sacks of ballast were suspended outside the 
car, and it was therefore only neces- 
sary to cut the string round the 
mouth of the sack in order to empty 
the bag. Berson had learnt a good 
deal from his previous trips, and 
accordingly had a long night's rest 
before starting. He was conse- 
quently able to reach an altitude of 
23,000 ft. without the use of oxygen 
and without any serious inconveni- 
ence. At a height of 26,000 ft. he 
noticed that his heart was beating 
rather strongly when he happened 
accidentally to drop the tube con- 
nected to the cylinder of oxygen, 
"With a great effort he rose still higher, "^'" " ^'' "■"«''»»■") 

to 30,000 ft., when all the ballast was exhausted and the thermo- 
meter showed a reading of - 54° F, He was obliged to descend, 
though he was still in a physical condition to hold out longer, even 
at a greater height. On another occasion Berson and Dr. Siiring 
succeeded in reaching a level of 35,600 ft., which ia probably 
the greatest height at which existence is possible. A balloon 
with a capacity of 800,000 cubic feet was used, and in the middle 
of July, 1901, a trial trip was made, Berson and Suring being 
accompanied by Dr. von Schroetter of Vienna. The balloon was 
filled three-quarters full with coal gas, and rose to a height of 
25,000 ft., during which time Dr. von Schroetter carried out 
physiological observations. The training which the observers 

Fig. 171.— Baio-thermo-hjgro- 
graph, designed for recording 
balloons by Dr. Hergeeell, 
and made bj Bosch, of 



underwent was curious. Bert bad placed himself in a vacuutn 
chamber, where the pressure had been reduced to 9*75 in. of 
mercury in 85 minutes. A man named Moaso had withstood a 
pressure of 7'5 in., which corresponded to a height of 38,200 ft. 
Berson, Siiring, and Schroetter went into the vacuum chamber, 
and the pressure was lowered in 16 minutes to 8-85 in. The 
pump did not admit of a more perfect vacuum. At this pressure, 
rabbits were killed in 
IJ hours, but pigeons 
managed to survive, 
though they tumbled 
about helplessly on the 
ground. Schroetter 
made careful observa- 
tions on the pulse, rate 
of breathing, etc., and 
reports as follows: "We 
were now surrounded 
by an atmosphere at a 
pressure of 11"8 in. 
While the mercury was 
sinking, we noticed a 
feeling of lethargy, 
against which wa strug- 
gled by breathing as 
hard as we could. But 
this did not help much. 
Our faces became very 
pale with a somewhat livid colour ; our heads were drowsy, our 
legs trembled, our hands lost all power, and gradually we 
lapsed into a state bordering on unconsciousness. We breathed 
a little oxygen out of the receivers, and felt at once refreshed. 
All the distressing symptoms disappeared, and we seemed once 
more to be in full possession of bodily and mental faculties. 
The pressure gradually sank still further ; but as we continued 
to breathe oxygen, I was able to continue my observations on 
the pulse, reflex actions, dynamometer, etc. The pressure 



fell below 10-25 in., which corresponds to a hei!>ht of 28,000 ft. ; 
the observations were then concluded, and it was possible, even 
at this pressure, to smoke a cigarette." Hchroetter is satisfied 
that the balloonist is liable to be attacked by all the symptoms 
of mountain sickness. A sleepy, lethargic stite is induced, and 
the simplest Ibing requires a great effort. To stand up or to 
bend the body becomes a very exhausting operation. The muscles 
do not remain under control ; both sight and bearing are affected, 
and the mere effort of thinking is wearisome. 

Flo. U3. — The balloon, " Pruwia," belonging to the Aeronautical Observatory, n 
haying a capacity ot 300,000 cubic feet, ia being filial with gas. 

As an instance of the way in which the bodily and mental pro- 
cesses are affected, two specimens of Scbroetter's writing are here 
reproduced; the one was done under normal conditions, and the 
other under a pressure of 9'45 in. The trembling ot the hand 
is very noticeable, and the difficulty of focussing the mind is 
shown by the fact that the word wic/i is repeated, whereas 
nicht should have been written once. If the patient sits 
perfectly still, the loss of power takes place more slowly; but 
if the smallest effort is mode, such, for instance, as standing up 
or lifting the lightest thing, it is certain to be accompanied by 
ring or trembling. Shortness of breath and beating ot 



the heart are accompanied by severe headache ; the pressure of 
the blood decreases, while the rate of the pulse increaBes. 

On the trial trip, when the balloou rose to a height of 24,500 ft., 
aod the thermometer fell to —8° F., all Schroetter's conclusions 
were verified, and in particular it was found that the inhaling of 
oxygen was Rufficient to ward off most of the troublesome symp- 
toniB. The three observers were perfectly well, and able to 
undertake the most complicated measurements as well as to 

FlO. 174. — Herrvon Schroetter's ordinary handwriting. 
(Pliotogr»ph from Ziinli' " HOhenkUnu ond BtTBmuidsningBo.'') 

enjoy the view from the car. Schroetter considers that Sivel 
and Croc4 undoubtedly met their death through neglecting to 
take a sufhcient supply of oxygen, and possibly also through 
waiting too long before beginning to inhale it. Bert showed 
that one third of a cubic foot of air mixed with oxygen, and 
containing 70 per cent, of oxygen, is required per minute up to 
a height of 23,000 ft., but for heights above this pure oxygen is 
necessary. Therefore Croce- Spine Hi and Sivel ought to have 
taken 46 cubic feet of air mixed with oxygen, and 64 cubic feet 
of pure oxygen, and it is certain that their stock was nothing 
hke this. 


All preparations had bean carefully made when Berson and 
Siiring started on their record-breaking journey on July Slat, 
1901. They rose to a height of 35,400 ft., and calculated before- 
hand from theoretical considerations that human life woe impne- 
Bible at a height of 36,100 ft. Siiring's description of the ascent 
is as follows:— "At 10.50 a.m. the balloon 'Prussia' began to 
ascend. It bad a capacity of 190,000 cubic feet, and had been 
filled with hydrogen. It carried about 3J tons of sand and iron 
filings as ballast, and rose very gently in the air under a slight 

(Pbotognph ftom ZnnU " 

north-west wind, the sky being partially coveted with cirrus and 
cumulus. The balloon was rather more than half full and rose 
quickly but steadily; in 40 minutes it had reached a height of 
16,000 ft, and at this stage it had assumed a spherical shape. 
We bad with us four cyliaders of compressed oxygen, each hold- 
ing 35 cubic feet. Soon we began to turn to the right, and our 
course was directed somewhat towards the south of Potsdam. 
Before the start the temperature had been 74° F. ; it had 
now sunk to 19° F. We began to inliale oxygen at a height 
between 16,000 and 20,000 ft., but rather as a precaution and 
with a view to saving our strengtli than from any actual neces- 
sity. The balloon seemed to be rising steadily, and we threw 

T 2 



out large quantities of ballast continually, in ftmounts varying 
from 130 lb. to 330 lb. Then when a position of equilibrium 
was reached, a complete series of observations would be taken 
after which more ballast would be thrown out. 

"Besides the ordinary readings on the barometer, we took 
note occasionally of the readings given by two black-bulb ther- 
mometers, one of which was specially protected from downward 
radiation and the other from upward radiation. After three hours 

Fig. ITG.— The balloon, "Prussia," balf fall of gaa. 

we had risen to a height of 26,000 ft., and in four hours we 
reached an altitude of 29.500 ft., and soon after we eclipsed the 
record, which till then had stood nt 30,000 ft. This height had 
been reached on December 4th, 1894. The pressure was now 
less than 10 in., and the temperature was —26° F. Our 
sleepiness increased, which was not remarkable, seeing that 
we had bad only four or five hours' sleep the night before. But 
it got no further than nodding, and we roused one another from 
time to time. Each little effort seemed to require more will power. 
We had sufficient energy to carry out the readings and note them 
in the book, and we could also throw out the ballast ; but as for 



looking about us and determining the direction of our course, 
that was quite beyond us. After drifting along to the Bouth-west, 
we thought that we came into a calm region, and that Boon a 
breeze began to blow us back towards Berlin. After which there 
began again a slow drift towards the south-west, and at a very 
great height there was a strong west wind, which carried us 
rapidly towardB the east. 

Fig. 177. — The balloon, " I'ruaaia," getting tcadj for an fteccnt. 

" The last observation was made at 8.18 p.m. at a height of 
33,500 ft., when the barometer read 8*27 in., and the thermo- 
meter stood at —40° F, These figures were clearly written 
down in our notebook. We soon fell at intervals into a state of 
unconsciousness; Berson pulled the valve-rope several times, 
when he saw me dozing off. While pulling the rope, i.e., about 
5 minutes after the last recorded reading, he looked at the baro- 
meter, which registered exactly 8 in., corresponding to a height 
of 34,500 ft. At 83,500 ft. we had thrown out 400 lbs. of ballast, 


and our recording barometer shows that we were still ascending 
when Berson took his last reading. We probably rose another 
1,000 ft., and certainly reached an altitude of 85,500 ft., or 
possibly 86,000 ft. But at this moment the effect of the valve- 
rope began to be felt, and we began the downward journey. No 
doubt we passed from a state of unconsciousness into a heavy 
sleep, and we awoke in three quarters of an hour to find the 
balloon still sinking. It was then at a height of 18,000 or 
19,000 ft. We were still overcome by a feeling of great 
exhaustion, which was specially noticeable when we tried to 
move hands or feet ; and though we had regained consciousness 
completely, it was still impossible to do anything or to move 
anything or anywhere. Later we pulled ourselves together to 
such an extent that we had control over the balloon, but it was 
still quite impossible to resume our readings." 

The fact that the observers lost consciousness was due, accord- 
ing to Schroetter, to the method of breathing ; it is quite likely 
that they did not, as a matter of fact, inhale a sufficient amount. 
Sivel and his companions inhaled oxygen out of balloons ; at a 
later date compressed gas in steel cylinders was used, the 
cylinders being fitted with a rubber tube which ended in a 
mouthpiece of glass. There is a certain element of danger 
about this plan, inasmuch as it is possible for the mouthpiece to 
drop out of the mouth. Attempts have been made to use liquid 
air or liquid oxygen, but so far without any great success. 
Schroetter believes that accidents would be impossible if a 
mask were used. 

The methods used for exploring the atmosphere by means of 
recording instruments are being daily improved. It will, there- 
fore, be no great loss if the use of balloons with observers is 
abandoned, especially seeing that such ascents are much more 
expensive and laborious. It may, however, be remarked that 
these high ascents have not permanently injured the health of 
any of the observers, and that the ill effects pass off almost at 
once, as soon as the ground is reached. Still it must be admitted 
that Tissandier has become deaf as the result of his memorable 
ascent. Quite lately, too, the tympanum of a man's ear was 



cracked at a height of 10,000 (t., though he had previously made 
over 100 ascents, and had often reached heights oE 28,000 ft. In 
any cnse it is to be hoped that there will be no further attempts 
to hreak the record in this department. 

On njeteorological expeditions observations on atmospheric 
electricity ought not to be neglected. Tliere is much to be done 
in this field ; as a matter of fact, we know even nowadays little 
more than was known in the days of Franklin and his immediate 
successors. The potential 
gradients ought to he in- 
vestigated, as also the con- 
ductivity of the atii'.osphere. 
The term " potential " is 
used to denote the difference 
in physical state of two 
bodies carrying electrical 
charges. A body at high 
potential can only discharge 
by being placed in electrical 
coiitact with a body at lower 
potential, and potential 
gradients are measured by 
the fall over a given distance. 
The principal workers in this 
department are the French- 
man Le Cadet, together 
with Professor Bornstein, 
Dr. LinKe, Dr. Ebert, Dr. Gerdier 
Erner, Dr. Tuma, Dr. Schlein, etc. 

Lately meteorological observations have been made in Vienna 
at ihe instigation of Viktor Silberer. He has fitted out several 
such expeditions at his own cost, some of which have been 
curried out by members of the Aero Club, aucb as Dr. Scfalein 
and Dr. Valentin. Viktor Silberer has frequently had to apply to 
the Austrian parliament for funds and has not always met with a 
very ready response. Still it must be admitted that under rather 
disadvantageous conditions the Austrians have done good work. 

Professor Boltzm&nn, 



Meteorology has derived considerable benefit from balloon 
ascents and the astronomers have also done the same. The 
balloon is specially useful when it is a matter of observing some 
rare phenomenon which may be hidden by a cloudy sky. The 
first ascents of this kind were made by Spencer-Rush in 184B, 
and Welsh also did work under similar conditions for the Kew 
Observatory. On November 16th, 1867, Wilfrid de Fonvielle 
made an ascent in one of Giffard*s balloons for the purpose of 
observing falling stars. It has been already stated that the 
astronomer Janssen left Paris in a balloon on December 2nd, 

Fig. 179. — The shadow of the balloon is seen on the clouds, 

together with a halo, 

1870, in order to go to Africa for the observation of a solar 
eclipse, and this perhaps is some explanation of the interest 
which he has since taken in ballooning. Wilfrid de Fonvielle 
and Madame Klumpke made further ascents for the purpose of 
observing falling stars. In November, 1899, by international 
arrangement, several simultaneous ascents were made to observe 
the Leonids as they crossed the i)ath of the earth's orbit. In 
France Madame Klumpke and Count de la Yaulx made ascents, 
in Strassbur<j; the author in company with Dr. Tetens and Dr. 
Bauwerker did the same, wliile England was also represented. 
On the evening of November 15th, the sky at Strassburg was 
entirely covered with cloud ; consequently no observations could 
be made in the ordinary way. But from the balloon ten falling 



Btars were Been, five of which were in Leo, and consequently 
belonged to the group called the Leonids. There was, however, a 
slight miBcalcnlalion in the matter. It subsequently appeared that 
owing to disturbances caused by Jupiter, the maximum took 
place a day sooner than had been predicted, and the whole thing 
was on a mncli smaller scale than had l^een expected. In France 
and England ascents 
are made every year in 
order to observe the fall- 
ing stars, and this was 
also done in Germany 
in 1900. In Germany 
astronomers are apt to 
look askance at balloon 
observations, though 
Janssen and others are 
of a different opinion. 

At the conference at 
St. Petersburg the com- 
mander of the Spanish 
Balloon Corps, Don 
Pedro Vives y Viches, 
stated that he intended 
to organise a number 
of ascents for observ- 
ing the total ecIijMe uf 
the sun which would 
be visible at BurgoH on 
August 80th, 1905, and that he was prepared to offer a seat in 
the car to a member of the conference. Accordingly three 
balloons made the ascent at Burgos on the eventful day. Vives 
y Viches was on Iward one of them, and with him were a Spanish 
physicist and Professor Berson. Several meteorological questions 
were to be considered. In the first place it was to be ascertained 
whether there was a decrease of temperature during or aft«r 
totality. Berson stated that any fall in temperature would be 
very unlikely, seeing that at a height of several thousand feet 

Fin. ISO.— Tbe shadow of the batluon it cast on 
Ibe clondt, and the c&r is seen surrounded 
b; a rainbow. 


no effect is produced on the thermometer by the setting of the 
sun. It was further to be discovered whether the wind veered 
round through almost an entire circle ; the Americans Helm- 
Clayton and Ilotch asserted that this was the case, and they had 
already made observations of five total eclipses. 

The breadth of the zone over which the eclipse was total was 
only 112 miles, and it was necessary to prevent the balloon from 
being carried out of this zone before the event happened. The 
accent was therefore deferred till the latest possible moment, and 
the balloon only just succeeded in rising above the bank of 
heavy cumulus with which the sky was covered before the eclipse 
took place. It only lasted 3f minutes, and the astronomers on 
the ground level had a rare piece of good fortune when they saw 
the clouds clear away just at the moment of the eclipse. As for 
the balloon, it was only at the last minute that it succeeded in 
surmounting the clouds at a height of 12,500 ft. This was due 
to a curious accident. A large frame, 6 ft. square, had been 
covered with linen, and was intended for observing some of the 
peculiar effects of the eclipse. It had unintentionally been 
allowed to slip down during the ascent, and it was impossible to 
pull it up again. It consequently remained below the car in 
such a position that it caught most of the ballast that was thrown 
out. The situation looked serious until one of the occupants of 
the car noticed that they were over a mountainous district far 
from human habitation, and suggested that it might be possible 
with a bit of a swing to throw whole sacks of ballast, filled just 
as they were, without doing any damage. This was done, and 
they managed to ascend in time to see the eclipse. 

The results of the meteorological observations were that no 
decrease of temperature was noticed during or after the eclipse, 
and that no conclusions could be drawn as to the direction of the 
wind because the earth was hidden by clouds. Berson gave a 
description of the scene before the Berlin Balloon Club. The 
hky assumed a hue of many colours, and the flames shot out 
from tiie corona produced a marvellous effect, with the brightness 
of beaten silver. Tiie size of these flames seemed rather smaller 
than w^hen seen from the earth. The speed with which the 


shadow of the moon was chased over earth and clouds was 
tremendous ; this apparition was difficult to describe in words, 
and looked like the flight of some huge bird, shadowed against the 
clouds. The darkness was so intense that an electric lamp had 
to be used to read the instruments. When it is remembered that 
at any given spot the duration of a total eclipse is only 8 minutes, 
and that they are so rare as only to occur once in 200 years at 
the same place, it seems a wise precaution to prepare balloons for 
the event, in case of a cloudy day. 

The compass is a very necessary instrument in a balloon, and 
is particularly useful on a cloudy day, when intermittent glimpses 
of the earth are obtained through gaps in the clouds. It has 
also been proposed to use the declination and inclination for 
determining the exact position of a balloon above the clouds, but 
at present nothing is known of the application of such a method. 
Various optical phenomena can be observed from a balloon, such, 
for instance, as the aureole. An enormous shadow is cast by the 
balloon on the brightly lighted clouds, and the car appears to be 
in the middle of a rainbow. Sunrise and sunset either over the 
water or in the mountains are wonderful sights, and anyone who 
has once seen them is not likely to forget it. 

Balloons have also been used on Polar expeditions. The main 
difficulty appears to be to make suitable arrangements for a 
journey that may be much longer than is expected, and also to 
be able to meet dangers caused by unexpected descents on the ice. 
The unhappy results of Andree's expedition will help to point the 
moral. More plans have lately been suggested for reaching the 
poles by means of balloons. Wellman and Count de la Vaulx 
propose to fit out an expedition for this purpose, and it can 
hardly be doubted that success will sooner or later attend the 
efforts of some of those who propose to float over the 
North Pole. 



It was on August 10th, 1839, that Arago made known to the 
Academic des Sciences the discoveries that had been made by a 
painter named Daguerre and a cavalry oflScer named Niepce. 
With the aid of light they were able to make pictures of any 
object, and with their discovery the modern art of photography 
had its birth. Arago suggested that the making of plans and maps 
would be much simplified, and a Frenchman, named Andraud, in 
1855 drew attention to the value of the bird's eye view as a 
piece of documentary evidence. But Andraud can hardly be said 
to have been the inventor of balloon photography, any more 
than Jules Verne with all his adventurous tales can be called 
the inventor of the dirigible airship. A man, named Nadar, 
in 1858 was the first actually to take photographs from a balloon, 
but in those days the method of operating was very cumbrous. 
The original process consisted in the preparation of the photo- 
graph on a copper plate, that is to say, one finished product 
corresponded to one exposure ; from this, the next stage consisted 
in the idea of the ** negative," from which any number of 
" positives " could be printed. Still even so, wet plates had to be 
used, and it was necessary to expose and develop them 
immediately after they had been prepared. Naturally a process 
of this kind did not readily lend itself to balloon work. 

According to the wet process the glass plate was covered with 
iodised collodion, and then dipped in a bath of silver solution. 
If such plates are used, they must be exposed and developed 
before they become dry, otherwise the silver iodide crystallises 
out and no picture is obtained. Nadar made his first attempt 
in a captive balloon, in the car of which he had fitted up a sort of 
dark room, consisting of a round tent made of an orange-coloured 
material and lined with black. The ascent was a very costly 


affair, but was unsuccessful owing to an accidental leakage of coal 
gas from the balloon, which spoilt the plates. The reason of this 
was that the car was too close to the inflating tube of the balloon, 
a defect in the design which was common enough in those days. 
On a later occasion he succeeded in taking his photograph on 
freshly prepared plates and then descended immediately for the 
purpose of developing them. This plan worked well and was 
always adopted afterwards. During the war between Italy and 
Austria, he was invited by the Italian Minister of War to take 
some balloon photographs of the enemy's position at Solferino, 
but these attempts turned out failures. 

Two or three years later we find the art adopted in England 
and America. King and Black took photographs of Boston from a 
balloon, and Negretti, who had already done work in Italy with 
the encouragement of the king, now turned his attention to 
London, where he took photographs from a balloon. No details 
are known as to the results of these experiments. 

During the American Civil War, balloon photography was used 
for scouting purposes. An amateur balloonist, named Lowe, 
went up in a captive balloon at Bichmond, and took photographs 
of the fortifications in the neighbourhood, going as far as 
Manchester on the west, and Ghikakominy on the east. These 
exposures, when developed, showed the disposition of cavalry and 
artillery, together with all the earthworks. The several photo- 
graphs were divided by lines into a number of spaces, which were 
indicated by letters Al — A64, Bl — B64, etc. General Mac- 
Glellan kept one copy and Lowe kept the other, an arrangement 
being made by which Lowe was to communicate the movements 
of the enemy's troops to headquarters by means of the lettering 
on the maps. The system is still used, if the circumstances are 
suitable, as for example in the case of a siege. For the observer 
in a balloon, a photograph is much more convenient than a map 
for finding a given place; the effect of perspective produces 
distortions not shown on a map, and buildings, forests, fields, 
etc., are much more easily recognised on a photograph. On June 
1st, 1862, Lowe signalled from a height of 1100 ft. that the 
disposition of the enemy's forces showed they were intending to 


make a sortie. General MacGlellan was therefore able to make 
arrangements accordingly, and in the course of the same day 
much more useful information of a similar kind was sent to 
headquarters from the balloon. 

Some years later Nadar*s son continued the work, and made a 
series of photographs of Paris in this way in 1868, which may 
still be seen in the Mus^e Nationale. During the Franco-Praa- 
sian War Colonel Laussedat suggested that photographs of the 
German positions should be taken from a captive balloon, bat 
the attempts were unsuccessful. A photographer, named Dagron, 
made use of a dark room, similar to that originally used by 
Nadar, and with the help of one of Giffard's balloons, succeeded 
in taking some photographs of Paris of a size 11 by 8^ in., which 
were fairly successful. Triboulet first used dry plates on an 
ascent undertaken for meteorological purposes. He was an archi- 
tect by profession, and being much interested in meteorology, 
made an ascent on a very wet day with the intention of photo- 
graphing some of the rain-clouds. His well-meant efforts 
deserved a better fate. The balloon was driven down by the 
heavy rain, and he barely avoided a collision with one of the 
towers of Notre Dame, only to fall a minute or two later into the 
Seine. He was soon rescued from the water, but fell a prey to 
the authorities of the octroi, who had seen his balloon float in 
from the suburbs. They subjected him to a lengthy cross- 
examination, and finally insisted on examining his belongings 
in order to see whether he had anything liable to duty concealed 
about his balloon. His double-backs naturally caused suspicion, 
being then something of a novelty, and the plates were therefore 
ruined by exposure to the light. 

Excellent results were obtained by Desmaret in a free balloon 
in 1880. He made his exposures at a rather greater height than 
had been usual up to that time, and certainly worked in a very 
skilful and scientific fashion. He used a lens of 11} in. focal 
. length, and his pictures, which were taken on plates 8 by 10 in., 
showed every detail clearly, even at great distances. He was 
able to take an area of 10,000 square feet on one plate, reducing it 
in the proportion of 1 to 4,000. Most of his exposures were 



made through an aperture in the floor of the car, and the 
shutter was worked electrically. He determined the exact 
height at which the photographs were taken hy means of two 
barometers, and endeavoured to find the effect produced by the 
movement of the balloon, noting, as far as possible, the speed at 
the moment of exposure. Dry plates at that time were suffi- 
ciently sensitive to allow of exposures of a twentieth of a second, 
and be consequently got some very sharp pictures. The speed 
of the balloon was about 20 ft. per second, and it therefore 
travelled over a distance of 1 ft. during the exposure, a distance 
which was insufficient to cause any perceptible lack of sharpness 
in the detail. He also took some good photographs of the clouds, 
and enlargements of his results may be seen in the Conservatoire 
des Arts et Metiers. 

From this time onward, photographic work was continually 
done both in France and England. Shadbold took some photo- 
graphs of London, and Woodbury in 1881 proposed an arrange- 
ment by which captive balloons could be made to do the work 
without an observer. The plan was complicated but ingenious. 
The apparatus included a rotating prism, which supported the 
plates, the rotation being effected electrically by pressing a 
button at the ground level. The shutter was similarly 
worked. But it was found impossible in this way to obtain 
a photograph of any particular spot, and naturally enough 
there was generally found to-be some part of the mechanism 
which obstinately refused to work. Triboulet therefore proposed 
to mount a basket of wickerwork beneath the balloon on gimbals, 
and to arrange seven cameras so that their shutters could be 
simultaneously worked from below by the electrical method. 
Six of these cameras were pointed through openings in the 
sides of the basket, and one was directed downwards through 
a hole in the floor. In this way it was supposed that a fairly 
complete panorama would be able to be made, and contrivances 
of this kind have since been often suggested for military pur- 
poses. In the eighties, balloon photography was solely employed 
for military purposes in England and Germany; and in this 
connection, the names of Elsdale and Templer may be 


mentioned, as well as those of Tschudi, Hagen.aad Sigsfeld. In 
Austria, the first attempts at photographic work were made by 
Yiktor Silberer, who interested himself in this as in every other 
aspect of ballooning. He usually made his exposure dii'ectly 
after the start and while the balloon was still rising. During 
this time the horizontal motion is usually small, and the vertical 
movement does not largely affect the sharpness of the negative. 
Consequently it is an advantage to take the photograph during 
the time of ascent, assuming that the conditions are otherwise 

An amusing tale is told as to a dispute between Silberer and 

the man who had provided him with his photographic apparatus. 

The latter declared that 

I " 7 ' ■" " 1 he was entitled to describe 

I / / \ \ himself as having assisted 

ft I \ I in taking the phutographs, 

mgg^mm^ _, ! though in point of fact he 

HS^^^^\,_. I had never been in a bal- 

Bta^^^^' loon in his life. He 

I ^""^f*^ accordingly printed some 

of the negatives, and 

fiG.l8l.-TnU.u!ef.imnummicapi,arato. added words to the effect 

(Fn>m"I*PhoU««phte™B.lloi>,"byTl™«di«. ^.^^^^ ^^ ^^ ^^^^^ gjj_ 

berer to make the exposures. In fact he stated that it was an 
act of courtesy on his part to allow Silberer's name to appear 
on the photographs at all. He naturally found experts, both 
legal and technical, to help him in a court of law, and they 
endeavoured to persuade the jury that the photographer was 
perfectly correct in his attitude. Silberer pointed out that it was 
unreasonable to allow one man to undertake a polar expedi- 
tion at his own cost and make all the exposures, while another 
man quietly developed them at home and claimed all the credit. 
The jury eventually agreed that this view was sound, and Sil- 
berer, who had been accused of slandering his opponent, by 
calling him a common thief and a downright swindler, was 

Balloon photography has received much assistance from the 


modem improvements in the art of constructing lenses, which 
are now made of great focal lengths. In 1885 Tissandier and 
Ducom employed one having a focal length of 22 in., and this 
probably represents the furthest limit likely to be reached by 
the amateur. 

Cailletet has devised an arrangement for registering the 
heights reached in a balloon which does not carry observers. A 
camera is carried which has two lenses, both of which project 

Flo. 182.— The first photograph t*ken from a balloon in Anatria. It repreaeats 
the Reichsbrucke in Vienna, and was taken bj Viktor Silberer in 1885. 

their images on the same plate. One of these lenses is focussed 
on an aneroid barometer, and the other takes the view of the 
landscape in the usual way. By means of a piece of clockwork 
exposures are made at certain intervals, and fresh films are 
automatically rolled into position. The film therefore records 
the reading of the barometer as well as the view of the landscape. 
Cailletet had a method of checking the readings of the barometer 
by comparing the known distances between two places, aa 
measured on the ordnance map, with their apparent distance 
as measured on the photograph. The focal length of the lens 


being known, it was possible in this way to calculate the height 
of the balloon. He also devised an apparatus with nine lenses 

for taking panoramic views for naval purposes, ,which was 
brought into use at Lagoubran. The exposures were made 


electrically, and the results were successful in showing the 
details of all the forts over a radius of 4 miles. However, it is 
doubtful whether the result of further experiments on these lines 
has been altogether encouraging, from the military point of view. 
Photographs which are taken more or less at random from captive 
balloons carrying no passengers are liable to more than the 
average number of accidents, and these are already sufficiently 
numerous, even in the case of manned balloons. The handling 
of a camera in the confined space of a balloon is a very awkward 
matter, requiring much practice. The main difficulty lies in 
the violent movements of the basket. It is true that photo- 
graphs can be taken of a bullet as it is fired at a target, and 
this only requires an exposure of one hundred-thousandth of a 
second. But during that time the camera must be held perfectly 
still, and this is not always as easy as it sounds on a balloon. 
We may consider the effect of the various movements of the 
basket on the photographer. These may be of four kinds, viz., 
(1) horizontal; (2) vertical; (3) rotatory; or (4) oscillatory. 
In the case of a captive balloon the horizontal motion is very 
slight, and may be almost neglected ; but this is by no means 
the case with a free balloon sailing along in a strong wind. 
Looking at the problem generally, let us suppose a line to be 
drawn from the camera to the object it is desired to photograph. 
Then the motion of the balloon may take place in the direction 
of this line, either towards or away from the object ; or it may 
be inclined obliquely to this line, the motion being either back- 
wards or forwards ; or finally it may be at right angles to this line, 
either to the right or to the left. Let us consider the last case, 
as the camera then suffers the greatest displacement with regard 
to the object. 

Let us suppose that it is intended to take a photograph of an 
object at a distance of 6 miles with a lens whose focal length 
is 8 ft. The object will therefore appear on the plate reduced 
on a scale of 1 to 10,560, and the movement of the balloon, in 
so far as it is directed along the optical axis, i.e., along the line 
joining the lens to the middle of the object, will produce no 
noticeable effect on the sharpness of the image. But consider a 

u 2 



point in the landscape, included in the ** object," which is at a 
distance from the camera of 6 miles and also at a distance of 
half a mile from the optical axis. The image of this point will 
be at a distance of 8 in. from the centre line of the plate. If 
the balloon is moving at the rate of 80 ft. per second in a 
direction at right angles to the optical axis, and if the length 
of exposure is one-hundredth of a second, then the balloon will 
move in this time over a distance of 0*8 ft. The image of the 
point under consideration will then be displaced on the plate by 
an amount equal to 0*00084 in. Generally speaking, it is fair 
to assume that a displacement of 0*004 of an inch does not affect 
the sharpness of an image, and in the given case the displace- 
ment is obviously insufficient to produce any effect whatever on 
the picture. Of course, it is immaterial whether the object 
moves or whether the balloon moves, so long as the movement 
is insufficient to produce a noticeable displacement on the plate. 
If the state of the light is known, or, in other words, the length 
of exposure is fixed, it is possible by simple calculations of this 
kind to find the most suitable height or distance from which to 
photograph a given object. 

Dr. Stolze has given a table by which the length of maximum 
exposure can be seen at a glance, provided the speed with which 
an object moves is known, and also the distance of the said 
object from the lens. The table is drawn up on the assumption 
that the want of definition is not to exceed a displacement of 
0004 of an inch on the plate. 

Batio of distance of object to 
the focal length of lens. 




Speed of the object in feet per second. 









The vertical movements of a free balloon need hardly be 
considered, seeing that the photographer does not begin to 
make exposures, as a general rule, until a position of equilibrium 


is reached at the desired height. But it is very much the reverse 
with captive balloons. 

Rotatory movements usually only happen with a free balloon 
at the start ; at a later stage they are of such rare occurrence 
that they may be almost neglected. Here again the case with 
kites and captive balloons is very different. Let us suppose 
that there is a comparatively slight rotatory movement, amount- 
ing to an angular displacement of 5 degrees 48 minutes a second. 
The tangent of this angle is 0*1, and if the distance of the object 
is 10 miles, the optical axis will be displaced through one mile 
in one second at the point where it meets the object. If the 
exposure lasts one-hundredth of a second, the optical axis will 
be displaced in this time through more than 60 ft., with the 
result that the negative will be hopelessly blurred. It is there- 
fore necessary to find the extreme limit of rotatory motion which 
will allow of a sharp image, and this will probably be an angle 
whose tangent is about 0*001. The only way in which this 
angle can practically be found is to note carefully the rotations 
of the basket, and to make the exposure at the moment when 
the rotation in one direction has ceased and is about to give 
way to one in the opposite direction. At this moment the 
basket is at rest, in so far as rotation is concerned, and the 
exposure must be made forthwith. If the conditions are very 
carefully examined, it may possibly be found that a fiftieth part 
of the duration of a rotatory movement is available for a sharp 
image. Suppose the time of such a complete period of rotation 
is 10 seconds, there would, on this supposition, be only one fifth 
of a second in which to make the exposure, and it is hardly 
necessary to say that the taking of photographs under these 
conditions is a matter requiring much experience. 

Horizontal movements of the balloon exert less effect upon the 
sharpness of the image, the greater the distance of the object 
from the lens ; with rotatory movements the reverse is the case, 
and the nearer the object, the sharper will be the image. Oscil- 
latory swings, like those of a pendulum, mostly occur at the 
start, particularly if the envelope is not vertically above the 
basket; but they disappear very soon. In the kite-balloon they 


are seldom met with, but with captive balloons they are of fre- 
quent occurrence. It is obvious that these oscillationa ma; pro- 
duce very serious consequences on the negative. Dr. Stolze says 
that the basket performs an oscillation in i seconds, if it is at a 
distance of 50 ft. from the top of the balloon. Consequently in 
a tenth of a second it will perform one-fortieth of an oscillation. 

Fio. 184. — Eastern KailwBj Station, in Bndapesth. 
(PhDtognpli bj Lieutenant Kret.) 

Let us suppose that a complete oscillation extends over an angle 
of two degrees, and that tbe time of exposure is to be one-tenth 
of a second. Then the basket in this time will oscillate through 
an angle of three minutes, and this will cause an entire blurring 
of the image if tbe object is at a distance of 5 or 6 miles. 
Oscillations of this kind are always larger in the case of small 
balloons, and it is not possible to neutralise their effect by 
decreasing tbe time of exposure. Dr. Stolze has made use of tbe 
principle of the gyroscope in this connection. He arranges two 


discs on axes at right angles to one another, and these are capable 
of being rotated by means of strings. The discs are joined by 
means of a ball and socket joint to the camera, which hangs 
below them, and in this way the combination is practically 
uninfluenced by the oscillation of the balloon. Spherical 
captive balloons are now more or less out of date, and these 
gyrostatic complications may very well keep them company. 

It is therefore evident that many factors enter into the calcu- 
lations of the length of exposure and that the right moment 
must be carefully chosen. The speed of the balloon is a most 
important factor, but as every photographer knows, the actinic 
value of the light is more important. Some compromise is 
therefore often necessary. But in so far as the value of the 
light is concerned, the balloonist has certain advantages, and hi'5 
exposures are generally much shorter than those which are neces- 
sary at the ground level. Let us suppose that with a given 
aperture and a fairly good light, an exposure of one-eightieth of 
a second is needed, and in bright sunlight one-hundredth of a 
second ; then it is generally found that these can be reduced by 
about one-half if the exposure is made from a balloon, and that 
one hundred-and-fiftieth of a second will generally be ample. 

The peculiarities of the light at great heights can be illus- 
trated by a simple experiment, due to Miethe. Take a piece 
of white paper, and hold it over the edge of the basket in a 
vertical position on the side where it is not exposed to the direct 
light of the sun. Then look directly over the upper edge of the 
paper at the earth beneath, and it will at once appear as if the 
piece of white paper were the darkest object in the field of sight. 

The course of the rays through the air before they reach the 
balloonist's camera is very complicated. The ordinary photo- 
grapher generally confines his attention to those objects which 
directly reflect the light from the sun or sky, and such rays pass 
through a fairly homogeneous atmosphere direct to the camera. 
But with the balloonist things are very difi'erent. The rays of 
the sun first penetrate through the dense atmosphere till they 
reach the illuminated object; thence they pass back again 
through the atmosphere till they strike the lens at a much 


higher level, and are refracted and to some extent absorbed 
on the way. It is fair to suppose that the movement of the 
breezes at different levels produces very little effect on the path 
of the rays, because such movements are extremely small during 
the moment of exposure. The main effect is due to refraction, 
and this depends on differences of temperature and atmospheric 
pressure. If the density of the atmosphere were everywhere the 
same, the refractive index would be constant, and no distortion 
of the image would arise ; but obviously enough, this is not the 
case. If the rays have to pass through a number of atmo- 
spheric layers, none of which are homogeneous, the refractive 
effect is likely to be great. It is well known that in the height 
of summer the air near the ground is in a state of motion owing 
to the great heat, and the middle of the day is therefore avoided 
for photographic purposes. Sigsfeld pointed out that if such 
air currents existed near the lens, they produced very harmful 
effects ; if, on the other hand, they were near the object to be 
photographed, they were quite harmless. In that case, the 
balloon has a decided advantage, because the air ir- the neigh- 
bourhood of the lens is always cool, when compared with that 
which is found close to the ground. The effects of absorption 
are of course undesirable. The air contains multitudes of solid 
particles, which not only reflect but also absorb light. These 
particles may be so numerous ns to amount to a mist or fog, and 
exist for the most part in the layers of the atmosphere close to 
the ground. In photographing an object on the ground level, 
the rays have to pass through a layer of these particles which is 
equal in thickness to the distance of the object from the lens ; 
such a layer is measured in a horizontal direction. But with a 
balloon the layer has to be measured in a more or less vertical 
direction, and as it is at the most only a few hundred feet deep, 
the balloonist is more favourably placed for photographing dis- 
tant objects. But in the neighbourhood of large towns, the 
atmospheric conditions are generally bad. Nearly every day 
there is a thick mist over Berlin, and the balloon does not rise 
above it till it has reached an altitude of nearly 1,000 ft. The 
wind carries a mist of this kind along with it, and one often has 



to travel 60 miles from Berlin before the last trace has dis- 
appeared. An instance of the way in which the path of the 
rays is affected is given by the results of the observations on the 
total eclipse of 1905. Professor Berson and a number of other 
observers stated that the sun's corona looked much smaller when 
seen from the balloon than when seen from the earth ; and, con- 
sequently^, Jannsen and other French astronomers are inclined 
to attach considerable importance to observations of such 
phenomena from balloons. 

The same care must be taken to study the variationti of the 
quality of the light when the photographs are made from a 
balloon as is the case with everyday photography. The 
actinic value of the light is a very variable quantity ; it 
depends on the season of the year, on the time of day, and 
. a multitude of other circumstances. It is greatest in mid- 
summer, and sixteen times as great in June as in December. 
Moreover, the light in the morning is better than in the after- 
noon. A ihin layer of cloud will absorb 40 per cent, of the 
sun's light, and if the sky is overcast the absorption may amount 
to 80 per cent. Direct sunlight is from eight to fourteen times 
as effective as diffused light from a blue sky, and white clouds, 
directly illuminated by the sun, add greatly to the value of the 
light. In the photography of mountains, the contrast between 
light and shade are apt to be rendered harsh owing to the clear- 
ness of the atmosphere, and this must be taken into account. 

Boulade has drawn up some figures which may help as a 
guide towards estimating the time of exposure, and take into 
account a number of variables. 

Co-etBcientB for — 

Time of year. 

JuDC. July, August ~- rO 
April, May — 1*5 

March, September =^ 2-0 
February. October =^ 3*0 
January, November =^ 4*0 
Decrmber ■— ."»*0 

65^ W. 


Condition of the Sky. 


glijfhtly cloudy - 

half covered - 


heavy clouds - 

_ 1 I 









Colour values muBt also be coDsidered. The eye sees no such 
differeDces between light and shade in a balloon as are noticed 
on the earth. The shadows seem to be so strongly lighted that 
in the distance they almost entirely disappear. The ordinary 
photograpli takes no account of colour as such ; the various 
colours are only distinguished from one another by patches of 
greater or less intensity. Light and shade are reproduced, but 

Fio. IH.-1.— Clouds o?er the Alps, 
(rhotosmph by SpelUrJnl.) 

a monochromatii: reproduction of a colour effect grades one 
colour into the next by a more or less abrupt change from light 
to dark. Nobody can nay exactly how dark a certain patch 
ought to be in order to give effect lo the colour of an object, and 
tills depends on the fact that the effect of a colour on the eye is 
by no means the ssime thing as the chemical effect of the colour 
on the sensitive emulsion. 

If we consider the Sun's spectrum those colours appear to us 
to be the brightest which are nearest the red end of the scale. 


Bed and yellow seem brigbt ; green, blue and violet seem much 
duller. But on a photographic plate the reverse ia the case. 
The blue and violet rays have the greatest actinic efTect, the 
red ones have the least. Consequently the print shows blue as 
white and red as black ; at least, it has this tendency, and the 
transformation actually takes place in extreme cases. Thus the 
chemical effect of the various rays of the spectrum on the photo- 

FiQ, 186. — Photogniph of a TlUage, taken in ilajlight bj the Vega CompBDj, of 
QeueTB. It ahonld be compared with the eimilar photograph taken by the 
Ught of a projector on the next page. 

graphic plate is altogether differeut from the physiological 
impression produced on the eye. Even if the colouring of the 
landscape does not appear to correspond to any particular colour 
of the spectrum, but to be made up of a number of components, 
each with its own peculiar physiological effect, the pbotograpbie 
reproduction will show a totally different grading. The bright 
yellow will still appear darker than it ought to be, and the dark 
blue will produce somewhat of the effect of wliite. 

This effect is exaggerated in balloon photography. The blue 


rays are more largely absorbed by the air than the otberB, and 
therefore all bright objectB appear redder and coneequently 
darker on the plate. An effect of absorption and reflection is 
that all the bright colours are, as it were, displaced towards the 
red end of the spectrum and the darker colours appear bluer. 
It is therefore necessary to supplement the effect of the brighter 
light, which is partially deflected or absorbed by the aqueous 
vapour and atmospheric dust, by using yellow filters. On the 
otiier hand, the chemical effect of the blue rays must be 

I. 187. — Photograph ol a TillaRe, taken at night, by means of an electric 
projector, bjr llie Vega Company of Geneva. 

restrained in order that they nmy appear darker on the plate. 
Yellow filters can therefore he used in a good light, because the 
time of exposure iu a halloon can generally be reduced. Probably 
the best filters are made by inserling a sheet of coloured gelatine 
between two sheets of glass with optically true surfaces, or a 
sheet of gelatine can even be used alone. Tiie filters should he 
used with suitable plates, which are so prepared as to have a 
tendency to emphasise the red values. For instance, plates can 
be obtained which give a brighter value to yellow than to blue, 
. but any given plate has a tendency to emphasise some particular 
colour. In any case, such plates give a better result than the 
ordinary kind. The Perxanto plates, prepared according to 


Miethe's method, give good results, and have the advantage 
that they allow of a shorter exposure than is required with 
filters, and this is a great advantage in dull weather. Such 
days occur so frequently that photography is really only 
practicable on about one third of the days in the year. If it is 
necessary to choose between filters and a good brand of 
isochromatic plates, the latter are much to be preferred. 

An interesting application of the use of projectors in balloon 
photography has lately been made by the Vega Company, of 
Geneva. A given place is photographed from the balloon by 
daylight, and then at night a further photograph is taken by the 
light of an electric projector. The plates are then developed 
and compared. It is suggested that in this way it might be 
possible to discover the places where earthworks are being 
constructed by an enemy at night, and the method would seem 
to be capable of useful application. 

the photographic outfit for balloon work. 

The Camera. 

The main points about a camera for balloon work are simplicity 
and rigidity. It is perhaps not easy for a man who has never 
been in a balloon to understand the conditions under which 
exposures have to be made. He may be a capable amateur 
photographer without having any idea of the most suitable 
apparatus needed for an expedition of this kind. He would 
probably suggest a Kodak, or some other form of hand camera, 
with which he had already done much good work on his holidays. 
Cameras of this kind are, however, altogether useless in a balloon, 
because the focal length of their lenses is too short. The object 
will be possibly at a distance of some miles, and with short focal 
lenses it is impossible to get any result at this range. Generally 
speaking, balloon photographs show little detail, and, of course, 
a great amount is unnecessary. But with lenses of very short 
focal length, the size of the image is so small that it would be 
almost impossible to see anything. A further objection to these 
cameras lies in the general complication of their mechanism, 
which would probably cease to work altogether after it had been 
exposed for a short time to the fine sand, which is always 
floating about a balloon from the ballast sacks, and it need 
hardly be said that the idea of repairing a camera in a balloon 
is almost out of the question. 

The fact that the focal length of the lens must be at least 
8 in. makes it necessary to use an apparatus of some con- 
siderable size. The limited space which is available must 
also be taken into account, and this excludes the use of very 
long cameras. Probably the greatest focal length of lens which 
can be usefully employed by the amateur is about 24 in. The 



best thing is a simple wood camera, solid in construction and 
easily bandied; it must be sufficiently rigid to be able to 
withstand the inevitable jolts of a landing. It must not take up 
too much room in the car, and the best plan is to mount it on 
the side of the basket in a leather case. The lens must be 
carefully protected by a soft covering of felt, or something of 
that sort, and it is then less likely to be damaged on coming to 
the ground. Cameras with bellows are not to be recommended ; 
they are hardly strong enough, the bellows may be injured and 
cease to be light-tight, and one can never be certain that some 
jolt has not bent the framework holding the double-back slightly 
out of the perpendicular. Still one of the smaller folding 
cameras with a lens of focal length between 8 and 12 in. may 
well be used if the struts holding the lens front are of thoroughly 
solid construction. But if a lens of focal length greater than 
12 in. is employed, the struts must be more solidly constructed 
than usual, and a better plan is to use a camera made throughout 
of wood in the most rigid possible manner. 

The use of tripods in balloons is quite out of the question. 
The best plan is to move the camera into any desired position 
by hand, which can always be done. Possibly an exception 
would have to be made in the case of cameras having lenses of 
very great focal length, e.g., over 24 in. long, or in the case of 
dirigible balloons where the vibration of the machinery would 
make photography a difficult matter. It used to be the fashion 
to point the camera through a hole in the floor of the car in 
order to direct the lens towards the ground beneath. But this 
is not actually necessary, and the attempt to point the lens 
vertically downwards is likely to be unsuccessful. If the optical 
axis is more or less inclined to the vertical, it makes no great 
difference ; it is easy enough to make allowance for anything of 
this kind later on. Besides which, it will only be in the rarest 
cases that the balloon floats immediately over the spot which it 
is wished to photograph. Another objection is to be found in 
the fact that this arrangement is very cumbersome from the 
point of view of those who have to do with the navigating of 
the balloon ; it is not always easy to throw out ballast or let 



down the guide-rope if a camera ib on the fioor almost beneath 
one's feet. And from the point of view of the photographer 
himBelf, the arrungement has Uttle to commend itself ; he has 
to bend down over his camera ia a very awkward position, and 
probably ends by making his exposure at random without know- 
ing exactly in what direction the lens is pointing at the moment. 
If it is actually necessary that the^ plate should be horizontal at 
the moment of exposure, the best plan is to mount a level on the 
camera ; the floor of the ear is very unlikely to be sufficiently 
steady, if only for the very simple reason that it contains a 

FiQ. 188. — Dncom'g pbotogniphtc 


(From Plulgliellla " Hsndbooli for 

constantly shifting load. This plan has therefore been 

Various arrangements have been suggested by which the 
camera is mounted on the outside of the basket, and in this 
way it is generally possible to make the exposure at a con- 
venient moment. The distance at which it must be mounted 
from the edge depends on the angle of the lens ; no part of the 
basket must come within the field of view. But this arrange- 
ment has the disadvantage that it is only possible to photograph 
the landscape on the one side of the balloon, and it may happen 
that this is not precisely what is wanted, either owing to the 
position of the sun or for some other reason. It is largely a 
matter of pros and cons, and if the ideal is unattainable, one 


must be none the less content. The camera must in any case be 
so arran(:;ed as to be movable about horizontal and vertical axes, 
and this allows a certain reasonable latitude. 

In 1885 Jacques Ducom designed an arrangement by which a 
camera, taking half-plates, was supported on the outside of the 
basket. It was movable about a horizontal axis, and could there- 
fore be inclined at any angle to the vertical, but no allowance 
was made for any other motion. Lieutenant von Hagen, of the 
Prussian Balloon Corps, devised a similar method by which the 
camera was screwed to a bench, which was supported on an 
angle-iron fitted to the side of the basket. The bench wa-^ 
capable of being tilted about its outer edge, and there was n 
scale for reading the inclination to the vertical. It was also 
capable of motion about a vertical axis. Hagen thought it 
would be necessary to focus for each exposure, and this added 
to the complication of his apparatus. He therefore had a 
focussing screen of quarter-plate size, which was placed above 
the main carrier, and was used with the same lens. The camera 
was intended to be used with whole plates, and the lens was first 
placed in front of the focussing screen, its position being very 
carefully adjusted. After this had been done it was unscrewed, 
placed in position below for the plate, and the exposure made. 
Evidently this must all be done very quickly if the balloon is 
moving fast, and it is desired ta take a photograph of a given 
spot. In a captive balloon, the method would be altogether 

There is a further objection to the use of cameras with 
bellows. The frame for carrying the plates is hinged to the 
bottom board, and if the camera is pointed vertically downwards 
there is a tendency for the upper end of this framework to fall 
downwards. The lower part of the plate will therefore be 
further from the lens than the upper portion, and conse- 
quently the image will not be sharp over the whole of the 
plate. Hagen met this by having two scales, running the whole 
length of the camera, the one being attached to the base and the 
other connecting the frameworks of the front and back at the 
top; when the adjustment was finally made, and the clamps 

A. X 


were fixed, the readings on the two scales were the same. In 
folding cameras with struts, this is unnecessary, seeing that there 
is no tendency lor the plate to fall towards the lens. Hagen sac- 

i in getting some excellent results with his apparatus, and 
these were exhibited in 1886. 

It has been proposed to support the camera on gimbals in 
order to njake it independent of the vibrations of the balloon. 


But this has not proved a success, and the necessary movements 
which are required to make an exposure always communicate a 
certain amount of vibration. If the apparatus is very heavy, it 
may be suspended from the ring, but even in that case it is 
necessary to have some fixed support on the edge of the basket 
at the moment of making the exposure. But cameras of this 
size are very seldom employed, except possibly for photographing 
the sun's corona during an eclipse. A little contrivance, men- 
tioned by Pizzighelli in his "Handbook for Photography " of 1891, 
may be useful in judging a suitable moment for making the 
exposure. A vertical pointer is fixed to a board, and throws its 
shadow on a scale upon the edge of the board. The movement 
of the shadow will give some idea of the motion of the balloon. 
But it is very easy to over-estimate the value of such a device. 

It is well to know the inclination of the camera to the 

horizontal at the moment of making an exposure ; but with 

Hagen's apparatus it is only possible to find the inclination of 

the camera to the iron baseboard. This is of little use unless 

the inclination of the iron support to the horizontal is also 

known. The better plan would be to have a level fixed to the 

camera, and a scale by which the inclination of the level to the 

optical axis could be determined. But great accuracy would 

hardly be possible, even if a second observer were available for 

adjusting the level at the moment of exposure. In 1890 the 

Prussian Balloon Corps adopted a method by which the camera 

was mounted at the end of a rifle in a thoroughly substantial 

but rather primitive manner. On the right hand side of the 

apparatus a quadrant scale was fixed, by means of which the 

inclination to the vertical could be read by noting the position of 

a plummet with regard to the scale. At the moment of making 

the exposure the cock of the rifle was depressed, and fell against 

a lever which released the spring working the shutter, and at the 

same time locked the plummet in the position in which it 

happened to be at the moment. In this way it was possible 

to determine the inclination to the vertical with accuracy after 

the exposure had been made. 

Baron von Bassus described a similar construction in 1900J 

x 2 


and as he was working quite independently of the Prussian 
Balloon Corps, he probably knew nothing of their methods. 
The camera was mounted at the end of a rifle, and by means of 
a quadrant scale it was possible to determine the inclination of 
the optical axis to the barrel of the gun when the camera was 
fixed in position at any suitable angle. A small spirit level is 
mounted on the barrel oE the gun, and its image is reflected from 
a mirror into the eye. As soon as it is seen that the bubble is 
in its central position on the level, the trigger is pulled and the 
shutter is released. At the moment of exposure, the barrel of 
the gun is therefore horizontal, and the inclination of the camera 
to the vertical can be read off the scale, being in fact the incli- 
nation of the camera to the barrel. This construction has the 

Fig. 191. — Baron von Bassus' rifle apparatus. 
(From the Ilbistrierte Aeronaut ische M Uteilungttu) 

advantage of requiring only one network to interpret the results 
of the various photographs taken with one setting of the camera, 
but, on the other hand, it labours under the disadvantage that it 
is impossible to focus the lens on any given object, as it is more 
or less a matter of chance what may happen to be in the field of 
view. Still there may be cases in which it is necessary to make 
an exposure directed towards some particular object. To some 
extent this may be done by mounting a second mirror on the end 
of the camera at such an angle that the field of view is reflected 
into the eye ; but it will seldom happen that any very certain 
aim can be taken in this way. 

Vautier-Dufour and the astronomer Schaer of Geneva have 
designed a novel type of apparatus, intended for use with a long 
focus lens. This camera is constructed in two halves, placed one 
above the other. The leng is in the upper half, and the light. 


packed in ilg 


passing through the lens, is reflected by a mirror at the back of 
the upper half to another mirror at the front of the lower half ; 
it then passes from the lower mirror to the plate at the back of 
the lower half of 
the apparatus. The 
length of this 
camera is, there- 
fore, only one -third 
of the focal length 
of the lens. Thus 
with a lens of focal 
length 48 in., the 
camera would 
measure 16 in. 
from back to front, and with a compact apparatus of this kind, 
one has all the advantages of the bigger lens. 

It is needless to say that the camera must I 
solid leather case, well 
padded on the inside. 

In order to be able 
to curry as much ballast 
as possible, the weight 
of everything else car- 
ried in the car must be 
reduced to a minimum. 
Films are therefore to 
be preferred to glass 
plates. The weight of 
a film-holder carrying 
a spool for six exposures 
of quarter-plate size is only one-eighth of that of three double- 
backs holding sis glass plates of the same size. But films are not 
altogether satisfactory ; they vary algreat deal, and after being 
kept for some time their sensitiveness falls ofi'. The manu- 
facturers do their best to prevent disappointment by printing 



the date before which the films should be exposed. But this 
does not altogether meet the case. Films are liable to be injured 
by damp and heat. Great as are their advantages as regards 
weight the photographer will do well to use glass plates instead, 
unless of course the photographs are to be used for military 
purposes and intended to be sent by carrier pigeons. Flat films 
can only be recommended in the smaller sizes in spite of their 
many good points. The only thing therefore is to use glass 
plates if good results are 
to be produced. If a 
large number of expo- 
sures are to be made, a 
saving in weight may 
result from the use of a 
magazine camera hold- 
ing several plates. With 
cameras of the newest 
type it is possible to 
make about twelve ex- 
posures in half a minute, 
and from this it isevident 
that the changing of the 
plates is simply and 
quickly done. But their 
use can hardly be recom- 
mended, even if a type 
of magazine is used in 
which the changing of 
the plates is effected by simply turning them over in succession, 
and 80 preventing one plate from rubbing against the next. There 
is indeed a 6erious objection to their use, which lies in the fact 
that the changing of plates causes a great deal of dust to settle on 
the sensitive surface of the gelatine, and produces a partial blurring 
o( the image. There is no means of removing this dust before 
making the exposure. Further, the plates are very liable to be 
broken by being dashed against one another if the landing should 
be accompanied by any nolent bumping. So that we finally come 



fiG. 191.— Aiguille Verte, taktn with the 
Vantier-Dufour appanitiu by the Vega 
Company, of Gene»ft. 



to the coiiclusioD that nothing is better than the old doubie-back. 
The flexible shutters, used in some double-backa are not to be 
recommended for balloon work ; the linen backing is very liable 
to contain dust, which cannot easily be removed, and as the 
shutter is unrolled the dust may settle on the sensitive surface. 
The best plan is to use double-backs with vulcanite shutters. 
They are easily cleaned, and if they are rubbed with a piece of 
washleather they be- 
come charged with elec- 
tricity, and remove any 
dust that may be on the 
surface of the plate when 
they are pulled out. 
Another advantage lies 
in the fact that they can 
be pulled entirely out of 
the double-back. If a 
spring closes the slit in 
the double - back, the 
light is completely ex- 

Beginners are apt to 
pay insufficient atten- 
tion to the dust which 
collects on the plate and 
lens, and interferes with 
the sharpness of the 
image. It may become 
a serious matter in a balloon ; fine particles of sand from the 
ballast sacks float all over the basket, and have a habit of 
penetrating everywhere, even through the tightest joints. 


Usually everyone settles for himself the plates to be used, and 

has his own likes and dislikes. Novelties seldom find favour ; 

they are regarded at first with suspicion, and only after many 

trials do they cease to be novelties, and become trusted friends. 

Fla. l95.~Aigui11e Verte, taken with an 
ordiuarjr lens b; tlie Vega Companj, of 


But in balloon work, certain plates muBt be used iF good reeults 
are to be obtained, though doubtleee there is a certain latitude 

Films are light and convenient, but the reasons for preferring 
glass plates have already been explained. Films are seldom 
quite flat, and it is therefore impossible to get a perfectly sharp 
negative in consequence. The bigger the film the more uneven 
its surface is likely to be ; even the most modern devices do not 
entirely remedy the defect. For the smaller sizes of negative 
up to quarter-plate size, flat films in special carriers may be 
used. They are packed in black paper, and are placed in a 
special carrier against a glass plate, the paper being then pulled 

olT. After the exposure has been made a shutter is pulled out, 
and the film is shot forward under the action of a spring into 
a storage space, where they remain till they are to be develoi>ed. 
The stonige space is sufficient for thirty films. The whole 
apparatus is very light and convenient. But in the larger sizes, 
it is not possible to get a perfectlj- flat surface, and plates must 
therefore be used. 

For the prevenlion of halation, plates have a red coating on the 
hack of the film. The efl'cct due lo halation is the result of reflec- 
tion from the glass, and isverymarked in negatives showing strong 
contrasts ; but it seldom occurs in balloon work. The plate- 
holders must be well dusted before the plates are put in them, 
and the i>lates themselves must also be carefully dusted, other- 
wise poor negatives may result. Sometimes " solarisation " takes 


place, i.e., the negative becomes a positive, and all sense of contrast 
is lost. 

The Shutter. 

A good shatter should comply with the following conditions. 
It should be perfectly certain in its action, under all circum- 
stances, even after long use. It should be capable of giving 
exposures of different lengths, and it should distribute the light 
equally over all portions of the plate. The most rudimentary 
form of shutter is the well known leather cap, padded with velvet, 
which fits over the lens. But it is only suitable for time 
exposures, and consequently of little use in a balloon. Shutters 
which work automatically are the only ones worth consideration. 
They can either be placed in front of the lens, or between the lens 
and the plate, and a great variety of both kinds can be had. The 
simplest kind consists of an up and down motion of something of 
the nature of a flap, usually controlled by the pressing of a rubber 
bulb. Some sort of framework is necessary for holding it in 
front of the lens, but it may be said at once that this type is 
unsuitable for a balloon. 

The Iris shutters, by Voigtlander and Zeiss, are better ; the 
blades composing the shutter are quickly opened and closed by 
pneumatic pressure. But here again it is necessary to say that 
this is unsuitable ; nothing of the nature of a rubber tube can be 
used in a balloon, unless the photographer is prepared to go 
through endless trouble. The tube is easily caught in one of tlie 
many ropes of the balloon, and a sudden turn or wrench pulls it 
off; minor troubles arise when the camera happens to be standing 
on the tube, thus preventing the passage of the compressed air, or 
it may happen that somebody accidentally fires it off by touching 
the rubber bulb unintentionally. In any case, one hand is needed 
for pressing the bulb, and in a balloon both hands are necessarily 
occupied in holding the camera. Miethe's experience also tends 
to prove that these shutters work very irregularly at low tempera- 
tures, and this is of course a further disadvantage from the 
balloonist's point of view. The so-called falling shutters give a 
poor efficiency. 


The only one that can be recommended is the curtain shulter, 
the best Imown of which is probably the Thornton-Pickard. A 
long blind is mounted on rollers and has an adjustable slit in the 
middle, the rollers being placed both at the top and bottom. 
Before the exposure, the greater part of the blind together with the 
slit is wound round the top roller, the remainder being tightly 
stretched by the action of the bottom roller and covering the lens. 
A small lever is then pressed with the finger, and this releases a 
catch, allowing a sping to come into action and roll the blind 
quickly on the bottom roller. The slit therefore passes in front 
of the lens, and at the end of the operation the blind again 
forms a light-tight covering. As the slit passes the lens the 
plate is exposed to the light, and each part receives its image in 
succession. This arrangement works well, unless it should 
happen that some object in the field of view is in very rapid 
motion, in which case there would be some distortion of the image. 
But the time of exposure is very short, and it is only in very rare 
cases that it is necessary to take the motion of any object into 
account, and this never happens in balloon work. This shatter 
has an advantage which results from the successive exposures of 
the different parts of the plate. Suppose the camera to be 
slightly shaken during the exposure, it will be found that 
portions of the image are quite sharp while others show various 
stages of distortion. This results from the fact that the shake, 
such as it is, does not spread itself over the whole time of exposure. 
During some fraction of the time the camera is really at rest, and 
the image at such a moment will be sharp ; it is during the actual 
time of shaking that the corresponding portion of the image will 
appear in the negative to be blurred. The manipulation of a 
camera provided with this shutter is very convenient, seeing 
that it can be worked by pressing a single finger. 

An accidental exposure is only possible if somebody uninten- 
tionally touches the controlling lever, but in the latest models 
this is prevented by the provision of a safety catch, which can be 
lifted by a finger when it is desired to release it. A great 
advantage lies in the possibility of varying the length of the 
exposure by increasing or decreasing the width of the slit. The 



shortest exposure is about one thousandth of a second. The 
shutter is ^ound up by hand, and the spring does not come into 
action till the pawl is raised from the ratchet wheel by pressing 
the lever. The strength of the spring can be varied by winding 
it up to a greater or less extent, and a scale reading from 1 to 10 
is provided for the purpose : after use the spring should be left 
unwound in order to prevent it from losing its strength. The 
following advice may be given to the beginner. Adjust the slit 
to a certain breadth, say, one inch, and trust to varying the 
strength of the spring for regulation of the length of the exposure. 
In this way a little practice will soon show what strength of spring 
is required for a given exposure in a given light. But it becomes 
a difficult matter if both the breadth of slit and the strength of the 
spring are adjusted. The length of exposure can also be varied 
by suitable use of the stops. Arrangements allowing an adjust- 
ment of the slit from the outside are unnecessary in a balloon. 
A considerable experience of such contrivances tends to prove 
that they complicate the mechanism without producing any 
notable improvement. 

One objection to all shutters worked by a spring is that the 
latter gradually loses its power, and the times of exposure have 
a tendency to increase if no allowance is made. But one gradu- 
ally notices a thing of this kind; the slit seems to pass across 
the lens more slowly than before, and the necessary correction 
can be made. The working of the spring should be examined 
before undertaking an expedition. 

Various contrivances have been designed for determining 
exactly the length of exposure given by the shutter. The 
best and simplest consists in an apparatus, devised by Dr. 
Hesekiel, by which a hand, painted white, is made to revolve 
over a black background by means of adjustable weights, which 
drive clockwork. This is photographed by the camera, and the 
angle through which the hand has turned will be shown by a 
patch on the negative. By measuring the angular width of this 
patch it is possible to calculate the length of exposure which 
has been given. The face over which the hand revolves is 
divided into one hundred parts, and if the hand makes a 


complete revolution in a second, each division will correspond 
to 0*01 of a second. In 1886 Nadar used for this purpose an 
apparatus designed by Professor Marey and constructed by 
Richard, of Paris, which was taken on his balloon ascents. 

The Thornton-Pickard shutter works very well, and as it is pro- 
tected by being mounted inside the camera is seldom likely to get 
out of order. It also serves as a means of keeping dust out of the 
camera, and prevents any fine particles from settling on the lens or 
plate. Moreover it keeps out the moisture, and this is of import- 
ance, as it might otherwise condense on the surface of the lens. 

The Lens. 

The lens is undoubtedly the most important part of the 
camera; but the choice of the lens depends on many things, 
among which are the size of the camera, the make of plate, the 
quality of the light, etc. A lens has to do work under all sorts of 
conditions, and therefore it is not so easy to say exactly which is 
the most suitable. There are a large number of makers of repute, 
each of whom has his own peculiar method of manufacture. 

The first point to be settled is whether a telephotographic lens 
is to be employed, or whether a simple lens with long focal 
length is sufficient. The following explanations must be given 
to clear up the matter. 

Working with a simple lens the image of distant objects is at 
a distance behind the lens equal to the focal length. Therefore 
the ratio of the size of the image to that of the object is the 
same as that of the focal length to the distance of the object. If 
B is the size of the object, h that of the image, E the distance 

of the object, and / is the focal length, then b = - •; • There- 

fore if the distance is 100 times the focal length, the size of the 
object will be 100 times that of the image. In order to get 
large images of distant objects, it is therefore necessary to use a 
lens of great focal length. It is often suggested that it would be 
sufficient to take a small negative, and enlarge it in the usual 
way. But this is only possible within certain limits. Probably 
an enlargement which is five times the size of the negative is 

^^^ ^ 



t ^-^ ^S-w-JE . ' - 



A »- ^ ' ^ 







l'l» IW— UoBl UluB, M MM Emo MUM**: itMD ItftM^^^H 

A'itti a lens liaving a focal lengtli of Uu inches. 

itti a telephotcscopic lens of focal length lifty-three inches on a whole plate. 


the most that can be done. The grain of the plate becomes 
enlarged in the process, and obscures all the detail, if it is 
carried beyond a certain limit; and it is impossible in this 
way to conjure up any detail that does not exist in the original. 

There is another method by which a magnified image can be 
obtained. A lens is used which produces a small image, and 
this is enlarged by allowing the rays to pass through a second 
lens, and then to fall on the sensitive surface. This is called a 
telephotographic method, the whole being actually a sort of 
photographic telescope. The first lenses of this kind were 
made by Dallmeyer of London, and independently by Stein- 
heil of Munich and 
Professor Miethe of 
Berlin. They allow a 
considerable amount 
of latitude by using 
different focal 
lengths ; the only 
necessary matter is 
that the distance 
between the lenses 
should not differ 
from the sum of their focal lengths by an amount equal to the 
focal length of the back lens. 

The advantage of this arrangement is evident. The length of 
the camera can be considerably shortened, whereas with simple 
lenses of great focal length the camera must be of a correspond- 
ing size. It has been already stated that a focal length of 24 in. 
is the most that is possible for an amateur. 

It may now be well to consider why telephotographic lenses 
are not employed under all circumstances. The reason is that 
the image is not so sharp, and the intensity of the light which 
falls on the plate is reduced. If two lenses, each of a focal 
length of 8 in., are placed one behind the other, and the second 
lens magnifies the image five times, then the image is as large as 
if it were given by a lens of 40 inches focal length, but its bright- 
ness is twenty-five times less. Therefore these combinations can 

Fig. 197. — Diagram showing the relation between 
the focal length of the lens, the size of the image, 
and the distance of the object. 



only be used in moderatel; clear weather; iu dull weather they 
become useless, because under such conditions and with such 
lenses instantaneous photography would be impossible. 

Major Houdaille has stated that in his opinion telephotographic 
tenses are of no use in a balloon, but Baron von Bassus is not 
altogether of this opinion, thinking that they may do much 
useful work for military purposes. There is a good deal to be 
said for this latter view, hut, as things at present stand, the 

Fig. 200.— Pjraoiida of Cheops, Chephren, and Mencheica. 
(PlioUgreph by Spelterinl.) 

amateur will probably save himself some disappointment if be 
uses the simple lens. 

We must now consider the conditions attaching to the selection 
of a suitable single lens. The French Minister of War drew up 
a specification for lenses in 1900, when a competition was 
organised for the purpose of selecting the best. The condi- 
tions which were laid down still hold good, though for other 
than military purposes the requirements need not be so high. 
The specification called for a lens which was to be able at a dis- 
tance of 5 miles in any light (always excepting fog) to give a 
picture of a battery, in which all the details, including horses, 


men, wagons, guns, etc., should be distinguishable with the 
naked eye without the use of a magnifying glass. The lens 
therefore must have a focal length between 24 and 40 in. At a 
distance of 5 miles a man of average height appears on the 
image thrown by a lens of focal length 24 in. to be about 
0*005 in. high and 0'0016 in. broad, and consequently he could 
just be distinguished with the naked eye. The maximum length 
of the camera was to be 40 in. The sharpness of the negative 
was to be such that one man could be distinguished from his 
neighbour when standing at a distance of a couple of feet from 
him.^ The lens was further to be capable of being used with an 
aperture of F/10; with a focal length of 24 in. this stop would 
have a diameter of 2*4 in., so that with a dull winter light it 
would be possible to distinguish objects which were at a distance 
from* one another of F/10,000. This would require an aplanatic 
correction. Miethe considers that an aperture of F/20 ought to 
be possible in a balloon, seeing that the intensity of the light in 
a balloon is much greater than on the earth, but this would 
naturally not be the case in a very unfavourable light. At a 
distance of 1^ miles the lens was to be able to include the whole 
of a battery, 825 yards long, drawn up across the field of view. 
Assuming that there was an error of 2 per cent, in estimating 
the distance, an angle of 10^ would be required, and half-plates 
would have to be used. With a lens of this character work of 
the highest class can be done on plates of all the ordinary sizes. 
It would be better not to choose anything smaller than quarter- 
plate, and the most useful would probably be half-plate size. 

The prize in this competition was won by a French firm ; the 
second prize was adjudged to Voigtlander of Brunswick for a 
lens of 24 in. focal length with an aperture F/9 ; and the third 
to Zeiss of Jena for a lens of the same focal length, having an 
aperture F/8. Miethe considers that a number of other lenses 
would probably satisfy the conditions. Thus Goerz's anastig- 
matic lenses, Steinheil's antiplanat or aplanat, Zeiss*s protar, 

1 For the results of the competition of long focus lenses for purposes of military 
ballooning, see the Heme du Ginie Militaire, April, 1902, and the llhistrierte 
Aeronavtiiche MUteilungen, 1902, vol. IV. 


Voigtliinder's colliiiftrs, etc., are all good and caii be recommended 
as beiiif; o! equal quality, while of English makers the names of 
Ross, Taylor, Beck, Dallnieyer and man}' others might be men- 
tioned. The weight of the lens is probably a matter of minor 
importance as compared with its optical properties. Major 
Houdaille tidies the maximum weight at 6^ lbs. ; some of the 
competing lenses weighed 16J lbs. But it is doubtful whether 
anything is giiined if the reduced weight sacrifices any of the 
optical properties of the leus. 
It is certainly a little difficult 
to manipulate a camera with 
a very heavy lens at the front, 
and the best plan is to fasten 
a strap to the case, passing 
it round the body so as to 
take off some of the dead- 

The lens must be very 
carefully handled, and experi- 
ence seems to show that a 
few words on this subject will 
not be out of place. A very 
important point is to clean 
the lens by means of a soft 
camel's hair brush from any 
dust that may have settled on 
it ; the need for this is fairly obvious, and the reasons have been 
iiheady nientiont'd. It is necessary to pay special attention to 
any altenitions in the level of the balloon. As soon as it passes 
from a cold atmosphere into a warm, damp one, the surface of 
the lens will be covered wiih a thin film of moisture, and a 
blurred exposure would ref^ult. It is doubtful whether this matter 
iilwuys rcctivt's sullicieiit attention. Often enough the sky is 
[HTfectly cloar, and yet failur.-s are the only result. The cause 
is quite likely to be found in the fact that the lens has not been 
pr()perly cleaned. In a balloon, moisture is very frequently 
ilfi>osited on the lens. The camera has perhaps been put away 


in a corner of the basket, where it is well protected from the rays 
of the sun, and it has about the same temperature as the surround- 
ing atmosphere, which is generally far lower than that of the 
earth. A film of moisture has therefore probably coated the lens. 
It is possible to use a sliding tube of highly-polished metal to 
protect the lens from the sun's rays ; and if the sun is low down 
it might prevent its direct light from shining on the lens. The 
inner surface of such a tube must of course be coated with a matt 
black paint, in order to prevent any irregular reflection. 

The Development of the Plates. 

Every photographer knows that he can do much to save a 
plate which has not been properly exposed by suitably carrying 
out the developing process. The developer can be strengthened 
or diluted ; potassium bromide or caustic soda can be added, or 
a developer can be used which has already served for another 
plate. It would seem that balloon photography would derive 
much assistance from such methods, but this is unfortunately 
not the case. Development is a peculiar art. Everybody ha& 
his own special ideas and his well-tried mixtures, and he will 
hear of no others. In 1904 Miethe recommended the plan by 
which the plates were left to soak in a dilute solution for some 
time, as, for instance, in a solution of rodinal, containing one 
part in 250 parts of water. After an hour they may be taken 
out and carefully examined, when all the details will be seen 
very faintly. If the contrasts do not appear to be suflSciently 
vigorous they can be placed in another solution, containing one 
part in twenty, which has been prepared beforehand for the 
purpose. The whole operation takes two or three hours, if they 
have been properly exposed, whereas if the exposure has been 
too short, there may only be a sufficiency of detail at the end of 
five hours. The plates can be intensified or reduced as occasion 

In the light of experience, a totally different procedure must 
be recommended for balloon exposures, offering a better prospect 
of success. Professor Miethe has also changed his views as the 

A. Y 


result of some ascents he has made. In so far as the choice of 
a developer is concerned, rodinal can be recommended as being 
the simplest and the best. On the whole the best results seem 
to be obtained with it. Other developers have been tried, partly 
on general grounds and partly because rodinal causes with some 
people a soreness of the skin, which is unpleasant. But the 
change of developer has brought no improvement in the results. 
With rodinal it is quite easy to use rubber stalls, which protect 
the fingers from any unpleasant consequences. The whole 
manipulation is so simple that it requires little experience, and 
can be easily done even by the veriest tyro. 

A solution of rodinal is prepared, containing one part in five 
parts of water. The plate is soaked till it is nearly opaque to 
transmitted light, and black when looked at by reflected light. 
This usually takes place in five minutes at the outside. It all 
sounds rather primitive, but it is undoubtedly the most successful 
plan. Everyone who has made a number of balloon exposures, 
knows that if a solution of moderate strength is used, a plate 
often looks quite unaffected for some time, and then suddenly 
the whole thing seems to become fogged, and nothing further 
can be done with it. This is due to the bluishness of the atmo- 
sphere, which has more or less fogged the whole plate. It is 
not easy to tell with great exactness what is the state of the 
atmosphere, and on developing there is little opportunity to 
counteract it. The best plan is, therefore, to put the plate in 
a strong solution and to get out as much detail as possible in 
the shortest possible time. Many who have tried this plan have 
found it successful, and none appear to fail, so that the correct- 
ness of the procedure, simple as it is, may be said to be proved. 
Other developers also give good results occasionally, but rodinal 
is much the most certain in its action. Its simplicity gives it an 
added charm. 



Photographs which are taken from a fixed positioD are gener- 
ally intelligible without explanation, eBpecialty seeing that they 
are not usually concerned with eome very distant object. Balloon 
exposures produce a different impression on the mind, and one 


ha3 to accustom one's self to the bird's-eye point of view. The 
interpretation of an ordnance map requires some experience, 
and in exactly the same way with overhead photography it is 
necessary to learn to recognise the lie of the land. It is very 
difdcult, and, indeed, almost impossible, for a balloon photograph 
to show the unevenness of the landscape ; particularly is this 
the case when the balloon is at a great height, and the camera 


is pointed directly downwards. It is therefore well to say a 
few words about the means that exist for interpreting balloon 

It mny be pointed out in the first place that a balloon photo- 
graph often gives the impresBion that there are bills in the 
background, or at any rate that the level rises in passing from 

iberg in Wurttembiirg. 

the bottom to the top. This may be due to an effect of perspec- 
tive, or to the peculiarities of lighting. The appearance of 
villages is curious ; the houses look as though they had 
dropped out of a child's toy-box. The difference between light 
and shade is not very marked at great heights. The photograph 
of a place called Herrenberg, which is here reproduced, shows 
this very clearly. It was taken from a very moderate height, 
and it will be noticed that the shadows in the foreground are 
well marked, disappearing somewhat towards the middle and in 


the backgroand. The effect is still more marked at great dis- 
tances. The slope which appears on this photograph is well 
marked, and is emphasised to some extent by the low position of 
the balloon. It looks doubtful at first glance whether the whole 
town is on the side of a hill or whether the rise only begins near 
the church in the background. But a very simple sketch shows 
that the rise on the side of a hill would be much more marked, 
and the fact that one house appears to project above its neigh- 
bour is not enough to prove the ground to be hilly. The roads 
are very clearly visible, with their white dust and rows of trees. 
Country paths are often very indistinct, and could easily be 
overlooked altogether. There is always something charac- 
teristic about a railway, which catches the eye. But a light 
railway along the side of a road or a tram-line is not easily 

Fig. 204. 

found at once, even if its existence is already shown on 
the map. 

Roads are often a good indication of a change of level. When 
a road disappears, as in the photograph of Blankenburg, between 
the points /c-A*, it is easy to see that it is hidden from sight by a 
slight hill. It is not so easy to see that the part marked e is a 
considerable rocky eminence, called the Regenstein, so little does 
it attract attention on the photograph. But the fact that it 
hides the road between k and k shows that it is a hill, though it 
is impossible to say how high it is. The low level of the balloon 
is also shown by the way in which the peaks in the background 
stand out against the horizon. The irregularities in the direc- 
tion of the roads, and in the appearance of the ploughed land, all 
tend to show that the country is hilly. In the parts round a and 
h there are many gentle curves which fall gradually into the 
valleys or more evel ground lying among the hills. Such 


uneven lines as (lie Bliown between m and m would scarcely be 
possible on perfectly level country. An ordinary road is 
fienerally fairly straight and turns abruptly at a bend; in 


hilly country they become more serpentine in extreme cases 
vith many gentle curves. These peculiarities can be traced on 
the photograph of Rudersdorf, and in many of the others. The 
view of the chalk-pits near Riidersdorf is particularly interest- 
ing ; at a first glance the uneven nature of the ground is not 
very striking. The heights of the various points are shown in 
metres, and the incline of 1 in 4 in the foreground looks almost 

Flo. 206.— Blklersdorf. 

level. The number of small irregular pathways is also an indi- 
cation of the nature of the ground. They appear in great 
numbers on both sides of the railway siding, and would be 
clearly impossible on flat ground. 

The distribution of light and shade depends on the lie of the 
land, and conclusions can often be drawn in consequence as to 
whether the one part is higher or lower than the other. But a 
certain amount of caution must be exercised, seeing that a 
difference in the colour of the soil or in the nature of the 


vesctalion miij cnuse on appetti-imce o( shadow. Water is gene- 
mllj easilj recognised ; rivers run their course along well-delined 
carves, »luch are at once recognised on paper. They probably 
apiiear to resemble roads in so far as their brightness is 


concerned ; bat there is likely to be little chance of confusion owing 
to the different nature of their outlines. In the photograph of 
Riidersdorf, three bridges are to be seen, which of course clearly 
indicate a river ; besides which there are the shadows of the trees, 
and, further along, a small boat. 

Iq winter time things are rather different. The fields may be 
white with snow, and the roads black with sluBb and mud, while 
in the forest the paths may be still covered with snow, and 

FlO. 208.— Village in the Dckermarb in wi 

glittering in the dark trees. If the whole country is covered 
with snow, and yet shows a number of black patches, this is a 
clear indication of a forest, and if the trees are not too closely 
planted, they can often be distinguished from one another. 
Fields and country paths disappear in the enow, and it is 
only the rivers and roads that seem to be black. The rail- 
way, which passes through the middle of the photograph of the 
village in the Uckermark stands out from the snow, and the' 
telegraph poles can be seen at the side of the lines. The small 
declivity at the side of the line is shown by the dark patches. 


wbere the enow has been unable to lodge. In the photographs 
taken by Spelterini, the snow, rocks, and glaciers are always 
clearly to be seen. 

It will therefore be seen that a little practice is all that is 
required to interpret the photographic results, and to find out 
the principal features of the country. But much depends on 
the nature of the light, and this may tend to lead one astray. 

Fin. :iu;i, — (Jhjci isof ilitfLTcut ctilonrs. ])holOf;ra|ilievi from (liove. 

Mietlie'a system of colour i)hotography is a further useful guide, 
which can hartlly leave room for any doubt. 

It has been already stated lliat the use of yellow filters or 
isochromittic plates helps tlie photographic representation of 
colour to correspond more nearly to the impression produced on 
the eye. In any case, umrited differences of colour can generally 
beunderstood.especiallyif the photograph is compared wilh others, 
AVhite, yellow, green, black, and the various shades of brown 
and giey are the most usual colours in a, landscape ; in towns, a 


red tinge iB added by the roofs. Photographs can be taken of 
different enbetancea, euch as leaves, sand, straw, water, eart)iy 
soil, etc., and if they are grouped together close to one another, 
the contrast of colour becomes useful for reference. Bat the 
angle from which the objects are photographed makes a differ- 
ence, and this has to be taken into account. Specially is this 
the case with water, which appears white in reflected light, but 
may appear absolutely black if looked at directly from above. 
Dry, brown leaves will also appear whitish if placed in such a 
position that they can reflect light into the lens. 

Colonel Klassmann mentions the following points. The 
gradation of tone over a print may he either due to the different 

Fig, 210. — This photograph shows the same objecis as in the preceding, but it is 
taken from the side inntead ot being taken from above. 

colours of the objects or to the varying illumination. Supposing 
the illumination to be uniform, the brightness ot the various 
colours is in the following order, viz., white, yellow, grey and 
brown, red, green. Bright, polished surfaces often reflect so 
much light as to appear white, quite independently of what their 
actual colour may happen to be. The greater the distance of 
the object the less is the effect produced by its colour, and the 
greater the impression produced by light and shade. This effect 
is also produced on the eye when it looks at a distant object. 
The atmosphere produces so strong an impression on the plate 
that the distant landscape may he entirely blotted out, but colour 
photography is likely to make such a marked change that in ihe 
future we may expect to get plates with much greater detail than 



at present. The first attempts in this direction have lately been 
made by Professor Miethe and Dr. Lehmann, who have made 
some balloon ascents, and taken some photographs with a special 
form of camera. 

The methods of colour photography may be briefly explained 
as follows. The colours that appear in nature can be analysed 
into red, green and blue. With these three colours every possible 
tint can be produced by proper mixture. By the use of filters, 
it is also possible to separate the three colours out of any mixture. 
It used to be the plan to employ each 
filter in connection with a special plate, 
which had been so prepared as to be 
specially sensitive to the colour separated 
out by the filter ; three different kinds of 
plates were needed, the one being for red, 
another for green, and the third for violet. 
With the three plates, exposures are made, 
the one after the other, as quickly as 
possible. The camera has one lens and 
only one plate is used, a third of it being 
exposed behind the three filters in succes- 
sion. The whole thing is done auto- 
matically by pressing a rubber ball, and 
this changes the filters and the portion of 
P'^' the plate which is exposed. Colour 

photography is made very simple in a balloon by the fact 
that the three exposures can be made simultaneously, by using 
three lenses, one beside the other, the distance oE the object 
being so great that no trouble arises from parallax. If the 
three lensea are mounted so that their axes are at distances of 
about 8 in., and their focal lengths are from 6^ to 7 in., no dis- 
placement of the image due to parallax can be noticed if the 
balloon is 800 ft. above the ground level. 

Professor Wiethe's camera therefore consists of a solidly 
constructed box, containing the whole of the apparatus, the 
front ot which contains the three lenses, side by side, and has 
slight projections fitted to it in order to protect the lensea from 


any accidental injnry that might be caused by joUb or knocks. 
The inside of the box is divided into three compartmentg, corre- 
sponding to the three lenses. The plate is 8J by 9J in., and is 
similarly divided into three parts. The focal length of the leng 
is about 6^ in., and works with an aperture of F/4-5. Three 
carriers are provided for the filters, which are placed immediately 
in front of the plate. The camera has no focussing screen, 
seeing that it is adjusted once for all. A shutter of the slit type 
is used, and at the back there are the usual double-backs. The 
whole of the manipulation is done from the ontside, and the 
double-backs are fitted with rolling blinds. Isochromatic plates 
must be used, and they must be sufficiently sensitive to red light 
to take an exposure in a tenth of a second. The plates are pre- 
pared with ethyl red in the following manner. One ounce of 

Fig. 212.— Sliding screen carrier for three.colour photography. 

Miethe's ethyl red (cbinoline, chinaline, ethyl nitrate) is dissolved 
in 500 fluid ounces of alcohol, and forms a stock solution which 
must be kept in the dark. One fluid ounce of the stock solution 
is taken and mixed with 100 ounces of water. The plate is 
immersed in this mixture for two minutes and then washed in 
flowing water for another 10 minutes in the dark room. It is 
then dried in a draught in the hot oven for about twenty minutes, 
but not more than twenty-five minutes. The solution can be used 
for a large number of plates ; probably it is better to take half 
the above amounts, which ought to be sufficient for six or eight 
plates. The plates should be packed front to back, in which 
case they can be kept for months. 

The proper relative exposures for the red, green, and blue 
must be adjusted by means of suitable stops. The filters used 
by Miethe allow of stops of F/4-5, F/6-3, and F/16 for the red. 


gieen, and blue respectively. The speed of the shutter ib arranged 
to Buit the prevailing light, and the camera is either held by 
means of a hand-strap, or Js rested on the edge of the basket. 
The length of exposure may amount to one-tenth of a second, 
and it is therefore necessary to wait for a moment when there is 
no oBcillation in order to make the exposure. In Northern lati- 

Fla. 213.— Miethe'B camera tor three-colour photographj in a balloon. 
At Ibe top Is shown tb« front ]urt with tlic three l^anpt, and below lis«n the sliding scnen 

tudes, colour photography is only possible in a balloon when the 
weather is reasonably clear. 

The development of the negative is done in the usual way in 
the dark room by means of a moderately concentrated solution 
oi rodinal, containing one part in nine of water. Towards the 
end of the development, the plate is examined on the back, and 
the process is generally complete when the image begins to be 
visible through the plate. A transparency is then prepared, and 


this is treated in the usual way by Miethe's three-colour project- 
tion apparatus, or the negative may be enlarged and printed on 
one of the three-colour photographic papers. The projection 
apparatus gives far finer results than any print. 

It may be well to mention a special photographic method 
which emphasises differences of level. It is known that the 
plastic effect is produced by looking at an object with both eyes 
at once. If one of the eyes is closed, it will be seen at once 
that the sense of solidity is lost, as well as of size and distance. 
At a considerable distance, the plastic effect ceases, even if two 
eyes are used, and one only judges by experience as to the actual 
distance. Colour and the nature of the ground give some assist- 
ance; but with large uniform surfaces one is often liable to 
make mistakes. This is caused by the fact that the effects of 
parallax are too small. This has been artificially increased by 
using prisms, and to a larger extent by the use of the stereo- 
scopic camera, with lenses arranged several yards from one 
another. This undoubtedly adds to the plastic effect. The 
ordinary stereoscopic camera has two lenses, and gives excellent 
results if the distances are not too great. But for balloon work 
the parallax is still too small. This can be obviated in ordinary 
photography by taking two pictures, one after the other, from 
different points at some little distance apart. Experience shows 
that good results are obtained in this way if the distance between 
the two points from which the photographs are taken is from 1 
to 8 per cent, of the distance from the object. In photographing 
from a balloon the method must be slightly modified. It is 
first necessary to determine at what speed the balloon is moving. 
The camera is then directed at an object, the distance of which 
is approximately known from measurements on the map. The 
second exposure is made a few seconds later, the exact interval 
depending on the speed of motion. Strictly speaking, the 
proper effect will only be obtained if the balloon is moving at 
right angles to the line drawn towards the object. But even if 
this is not the case it is still possible to get fairly good stereo- 
scopic results, seeing that the distance of the object is generally 
very considerable. It is only necessary that the distance 



travelled by the balloon between the exposures, reckoned in a 
direction at right angles to the line of vision, should be approxi- 
mately 2 per cent, of the distance from the object. But even 
this is not so important as might be thought. 

If the balloon is moving very fast it is often impossible to 
make the second exposure at the right distance from the first. 
The best plan is therefore to have two cameras, fastened to the 
same baseboard. The plates in each are prepared and the speed 
of the shutters adjusted. The whole of the balloonist's atten- 
tion can be directed on the object to be photographed, and he has 
not to bother about changing his plates. If the object is at a 

Fig. 214. — Boulade*8 stereoscopic camera. 

distance of 1,000 yards, and the balloon is moving at the rate of 
10 yards per second, the second exposure must be made between 
one and three seconds after the first. 

If no great plastic effect is required, and the objects are not in 
the far distance, an apparatus described by Boulade can be used. 
This camera is of the nature of a prismatic telescope with 
increased parallax, and is very convenient. The lenses are at a 
distance of about 3 ft. from one another, their focal lengths being 
21^ in. Mirrors are arranged at the sides to receive the images 
from the lenses and to reflect the rays to two plates, which are 
placed with their backs towards one another. The length of the 
path of the rays is exactly 22J in., and the apparatus is easily 
worked after a little practice. 



Apparatus has already been described, due to the designs of 
Triboulet, Cailletet and others, which necessitated a rather 
elaborate outfit, and might therefore cause difficulties in remote 
spots. But it is just in such places, e.g., among the mountains, 
or in the polar regions, or in marshy land, that balloon photo- 
graphs might be extremely valuable. A Frenchman, named 
Batut, therefore proposed in 1880 to send up lightly constructed 
cameras by means of kites. The size of the kite would obviously 
depend on the weight to be lifted, and also to some extent^n the 
altitude to be reached. Batut used an ordinary kite of the Eddy 
pattern, 8 ft. 8 in. long, 5 ft. 9 in. broad, and weighing 4 lbs. 
The camera, together with all the other appurtenances in the 
shape of barometer, cord, etc., also weighed about 4 lbs. It was 
fixed to a block of wood at such an angle as to allow for an 
inclination of the kite to the horizontal of 83°. A time-fuse was 
arranged to release the shutter and to record the reading of the 
barometer. At the same time it rolled up a long strip of paper 
by means of a spring, and in this way the ' working of the 
apparatus was clearly seen from below. A German, named 
Wenz, had a similar method of working. 

Gradually a kind of sport was evolved for the purpose of taking 
photographs in this way, principally by scientific men. The 
American meteorologist Eddy took some excellent photographs 
of Boston in 1896. Thiele in Eussia and Scheimpflug in Aus- 
tria have also lately done good work. The former was com- 
missioned by the Eussian Government to make photographs in 
Transbaikalia, Transcaucasia, and other places, and kites seemed 
to him likely to be suitable for the work, seeing that a wind was 
always blowing in these mountainous parts. In 1899 he con- 
structed an apparatus consisting of seven cameras. The largest 

A. Z 


of theae took plates 9} by 9^ in., and was placed in the middle, 
pointing vertically downwards. The other six were arranged at 
the corners of a regular hexagon, pointing downwards at an 
angle of 10° to the horizontal. His first attempts were not very 
successful. At last he completed his arrangements, but it was 
then found that the plan was not altogether suitable. He after- 
wards built a lighter apparatus, and worked successfully along 
the coast and rivers. His first combination weighed 44 lbs., hut 
this was reduced to 13 lbs. in the later designs. Tbe lens, which 

Fio. 216, — IJatut's kite for photogmphi 

was an astigmatic one by Zeiss, bad a focal length of 2J in., and 
the plates were 4 j by 4^, subtending at the lena an angle of 88^ ; 
the photographs therefore overlapped one another by 14°. At a 
height of 200 or 800 yards, he was able with one exposure to 
cover an area of 40 square miles. The photographs were subse- 
quently enlarged, which naturally magnified any errors. For 
military purposes he devised a so-called perspectometer, by 
means of which all dimensions and distances were to be legibly 
marked on the photograph, after being magnified ten times. 

Captain Scheimpflug constructed a panoramic apparatus for 
similar purposes, having lenses with converging axes. His 


apparatus, together with an electric device for releasing the 
shutter, and, including levels and plates, weighed 10 lbs. He 
originally proposed to suspend the camera loosely from a box- 
kite; but it was found that by placing it inside the kite it 
remained far steadier and was also protected from injury on 
coming to the ground. A Frenchman, named Denisse, has an 
original method by which he shoots rockets into the air, and in 
this way makes photographic exposures. The shutter is released 
when the rocket reaches the highest point, and the camera is 
protected from injury by means of a parachute. The main 
difficulty is to focus the lens on any desired object. 

z 2 



The interpretation of these bird's-eye views for topographical 
purposes is a special science. It may be called photogranimetry, 
and tbe main principles have been expounded by Professor 
Finsterwalder, of- Munich, 
and others. But it woald 
take us too far to go into 
all the details. 

A photograph is here 
reproduced, which gives 
an idea of the perspective 
effect produced by a bal- 
loon photograph. A place 
called Rudow is here 
shown, and a net- work, 
such as that drawn on this 

N''"'fot, ^ ", photograph, is easily con- 

' T<'. , structed, if the altitude 

and the direction of the 
balloon are known. The 
general case cannot well 
be described, but a few 
particulars about this in- 
dividual photograph may 

tlic onlnnnce map. {^q of interest. 

The exposure was made at an angle of 67° 30' with a lens of 
14 inches focal length at an altitude of 2,600 ft. The vertical and 
horizontal lines, A' and I', are drawn through the middle of the 
picture. The distance between two outstanding jwints is then mea- 
sured and compared with that on the ordnance map. In this case 
it is found that the scale is 1 to 5,7C9. It may be stated that the 

!. 217.— The villii'.-e of Rmiow, as shown oi 


original \?as taken on a Tvhole plate, but in order to save space, 
it has here been somewhat reduced. From the middle of the 
network a line is drawn to P, making an angle of 67^ 80' with 
XX, and on this in the foreground a distance from the middle 
point equal to 6,800 ft. is measured ofif. The point P is thus 
obtained, and a perpendicular is drawn through P, cutting the 
line YY at H. If the central point is called 0, the triangle OPH 
corresponds to that formed by the lens, the point vertically below 
the balloon, and the object. The angle PHO is 67° 80', and HP 
is 2,600 ft. 

A line through H is drawn parallel to OP, and this cuts 
the line XX in the vanishing point, V. On the line YY 
arbitrary lengths are laid ofif, each measuring, say, 500 yards. If 
the points on I'l^ are then joined to V, the horizontal distances 
between these lines will be everywhere equal. It will be noticed 
that these distances appear to become less, and at the vanishing 
point they absolutely disappear. Similarly lengths equal to 500 
yards are laid off along OP^ and these points are joined to H. 
Through the points where the lines, drawn to H, meet XY, 
horizontal lines are drawn, and the distances between these 
parallels will be 500 yards. The eflfect of perspective in shorten- 
ing some of these lines and lengthening others is again very evident. 
By means of a simple construction of this nature it is possible 
to make allowance for perspective in any balloon photograph. 



The use of carrier pigeons was known to the ancients. It is 
reported that in the times of the Pharaohs, sailors used pigeons 
to send news to their families that tliey were on the point of 
returning home. Pliny relates that Brutus used them in 48 b.c. 
for military purposes at the siege of Modena. He was there 
besieged by Mark Antony, and sent the pigeons in order to invoke 
the assistance of his friends. The gladiators of Bome announced 
their successful feats to the provinces in the same way, and the 
orientals are said to have organised a regular postal system by 
means of the birds. The Sultan Nurr Eddin in 1167 communi- 
cated regularly with all the large towns of Syria from Bagdad, 
and similar means of correspondence were used between Syria 
and Egypt. For this purpose, blockhouses were arranged at 
intervals, where the birds were in the charge of the soldiers. The 
messages were fastened under the wings, and the Sultan received 
the letters with his own hands. 

Dutch sailors are said to have first introduced carrier pigeons 
into Europe, where they were called Bagdettes, after their 
place of origin ; according to other accounts, the Crusaders are 
said to have done this service. In any case, the birds were soon 
in common use in Italy and North Europe ; they were used at 
the siege of Haarlem in 1572, and at Leyden in 1574, and Venice 
in 1849, at all of which places the besieged kept up communica- 
tion with the outer world with the help of these birds. The 
well-known house of Bothschild in London organised communi- 
cation in this way in 1815 so that they might receive the earliest 
possible news of the outcome of the Battle of Waterloo. They 
consequently heard the result three days before it reached the 
Government, and it is reported that great gains were made on 
the Exchange in consequence. Before the introduction of the 


electric telegraph in 1850, banks, merchants, and newspapers 
used pigeons for conveying the latest intelligence ; their import- 
ance was recognised in all countries, and in many places they 
were kept at the cost of the State. Their breeding has now 
become a kind of sport, and is encouraged by associations 
founded for that purpose. 

Carrier pigeons played a very important part during the siege 
of Paris, which was completely shut off from the rest of the 
world in so far as other means of communication were con- 
cerned. Altogether 863 pigeons left the town in balloons, and 
of these only 57 succeeded in returning. Probably the reason 
for this poor result is to be found in the terrible weather of 
December, 1870, the whole month being cold and foggy with 
many heavy snowstorms. A large number of the birds were in 
Paris at the time, but they were not all employed. The siege of 
Paris was an entirely unforeseen event for the French Govern- 
ment, and although 800 pigeons were available, they had not 
been properly accustomed to their surroundings. The idea of 
taking them out of Paris in balloons was the suggestion of a 
Belgian, named Van Bosebek. The first attempt was made on 
September 25th in the balloon ** La Ville de Florence," which 
carried three birds ; and in consequence of its success, it was 
resolved to send birds by every balloon. Those of the Antwerp 
breed were the most successful, and several of them made the 
return journey on six occasions. A curious journey was that made 
by a pigeon which was set free from the balloon " Washington " 
on October 12th under very heavy rifle fire, and was only able to 
reach its home in Paris on December 5th. Many experiments 
have been made to find whether the flight of the birds is in any 
way affected by firing. It is certainly so in some cases, but, as 
a general rule, it seems that the birds are not deterred by the 
heaviest firing. 

During the siege it became necessary to harbour their 
resources, and consequently a great number of messages were 
sent by one bird. This was largely due to a photographer 
named Dagron, who reproduced the letters by microphotography 
in the following way. A number of messages, together with 


printed matter, are fastened to a l>oard, and then photographed 
by a camera provided with a very fine lens. The distance of the 
apparatus from the board determines the extent to which the 
image is reduced in size. Dagron succeeded in photographing 
about 1,110,000 words on a square inch of plate surface. If 
dry plates were used for such woik, the image would not be 
sharp enough to be read with a microBCope, so that wet plates 
had to be used, and these give an image which is sharp down to 
the minutest detail. Ah is well known, the plates must he pre- 
pared immediately before being used by dipping them in the 
sensitive silver solution afLer they have received a coating of 
collodion. By this process the upper surface is completely 
covered with a layer of the silver salt, 
whereas with dry plates the gelatine has 
a kind of grain which interferes with the 
sharpness of the imaga After it has 
been developed and fixed, the thin film 
of collodioD is stripped from its support. 
Its lightness is extraordinary. Assuming 
that the messages are reduced by photo- 
graphy in such a way that more than a k.o. Bio.-Photographic 
million letters can be printed on a square reproilactiuD ot mes- 

incb, then one ounce ot collodion film is sag-a on a reduced »caie. 
sufiScient to take nearly 250 million letters. The films were rolled 
up and secured beneath the wings of the bird, as many as 20 
such films being carried on one journey. When the bird arrived, 
the films were removed, pressed between glass plates and enlarged 
by means of a magic lantern. The words were thrown in this 
magnified form on a sheet, which was divided into sixteen squares, 
and clerks were employed to copy the words, each one having a 
square allotted to him. The messages were then delivered to 
their addresses. The microscopic reductions were made by 
Dagron at Tours, where he arrived on November 2l8t, after 
having left Paris in a balloon. Altogether 57 pigeons carried 
100,000 messages for the Government into the besieged cily 
together with a million private letters. 

The instinct which leads the carrier pigeon to return to its 


home has been the subject of much dispute. Some have ascribed 
it to a kind of magnetism, but this is obviously impossible, seeing 
that if the birds are blindfolded, they are unable to find their 
way home, even if they should only be a few yards away. On a 
dark night they are able to do nothing. A test of this kind 
showed that the bird alighted on a tree and waited for the day- 
light, when it at once returned home, though on a moonlight 
night it was able to find its way without difficulty. Pigeons 
always rest by night for this reason, and there can therefore 
scarcely be any question of ascribing the instinct to some 
magical property of which we have no conception. It is quite 
possible that the nightly rest is to some extent due to a desire to 
escape from the attention of birds of prey. The losses are apt 
to be great if the ground is covered with snow, even if the dis- 
tance to be travelled is very short, and this seems to show that 
the eye is unable to recognise its well-known landmarks. Added 
to this, the undoubted fact that they always wait till the sun 
rises before starting points to the idea that their movements are 
guided by the eye. It has been suggested that hearing plays its 
part, and that sounds help to tell the direction in which they are 
going. But this is very improbable, and gives no explanation of 
the way in which the return journey is made in a railway train. 
If the bird is sent up in some unknown neighbourhood it never 
starts off at once, but flies round in ever-growing circles till at 
last it finds its way. It then starts off at full speed, whereas the 
circles were described in a leisurely fashion. Possibly the sexual 
impulse plays its part in driving the bird home, added to which 
it knows well that it gets its food without exposure to any serious 
dangers. But its capacity for finding its way is due in the first 
instance to its keen sight ; secondly, to the part which memory 
plays ; and thirdly, to the speed of its flight. 

These things are best understood in connection with the 
breeding of the birds. There are two different kinds, namely, 
those from Antwerp and those from Liege. The former are 
strong, with long necks and legs. They have long beaks but 
the head is flat, and marked with wattles. They are broad in 
the breast ; the eye is surrounded by a circle of flesh, and the 


wings are long. The Liege bird is smaller, lower in the body, 
with short legs and toes. The beak is covered with small wattles, 
and is very strong and short, the head being convex in shape. 
Its eyes are surrounded with white or grey rings. The breast 
is full and muscular, and the wings are turned inwards and 
short. The Antwerp pigeon is said to be descended from the 
Persian bird and from the high-flier ; the Liege bird is said 
to be a cross between the rock pigeon, the high-flier, and the 
turbit. There have been many crossings between the Antwerp 
and the Liege types, and the carrier pigeon of to-day is the 
outcome ; in this way it has been thought to combine the homing 
instincts of the one with the swiftness of the other. In breeding 
the birds great stress is laid upon the appearance, the hand- 
somest birds being also the best carriers. A really fine bird has 
a proud and somewhat elegant bearing, with a slightly arched 
head, the forehead being in a line with the beak, which must be 
strong and without very thick wattles. The eyes must be sur- 
rounded by a narrow ring of a white or grey colour, and the 
breast must be strong and muscular. Regularity in the marking 
of the birds is the result of suitable mating. Breeding begins 
in the spring, about March 15th or April 1st. It may even be 
later, and depends on the state of the weather. It lasts till the 
birds begin to moult at the beginning of September. The bird 
lays two eggs, and the period of incubation lasts about eighteen 
days ; but the young are likely to be stronger if there is only 
one to the family. On the sixth or seventh day a thin aluminium 
ring is put round the leg of the young bird ; on this is engraved 
such information as would lead to identification. After twenty 
days, they are fit to take their own food and- drink, though a 
watchful eye must be kept over them. They soon learn to fly, 
and before long they reach the roof and describe circles round 
the house. They get good practice if they are sent up in all 
sorts of directions at a distance of two miles or so from their 

The real training begins when they are three or four months 
old. At intervals of three days they are sent up at distances 
varying from three miles upwards, but always in the same 


direction. The distance is gradually increased till they are able 
to do fifty miles or so ; and the next year this is increased up to 
120 miles. If the bird is very clever it may in its third or fourth 
year reach 600 miles ; but this is not the case with all. Before 
tlie training is begun the birds must be accustomed to their 
baskets ; too many must not be packed together, and they should 
have something to eat and drink before starting on the return 
journey. If the balloon is likely to come to the ground with a 
bump it is well to release the birds before reaching the ground. 
If the pigeons have to be used for military purposes during the 
moulting season a great number will probably be lost. The 
distances should therefore be as short as possible, and unless 
there is great urgency it is well to suspend their work dmung 
this time. Only males or females should be taken on the same 
expedition ; but if this is not possible the males should be kept 
apart from the females. The male will return to the nest in the 
hope of finding his mate, and it is well that he should not be 
disappointed; both should not be sent out at the same time. In 
the breeding season, the female is best left at home. 
. Good results can be obtained with young male pigeons shortly 
before their first mating season, or with females who have been 
brooding for about ten days. In the intervals of training care 
must be taken that the birds have plenty of exercise in flying 
about. It is as well not to hunt them out of their cot, otherwise 
they are apt to become shy and to delay their return. A better 
method is for them to be obliged to go some miles to get their 
food. The common dove flies every day to the fields to get food 
and the carrier pigeon can be accustomed to do the same. The 
best plan is to give them a moderate allowance of food at home, 
and then to take them out into a field, and scatter the ground in 
and around the basket with grain. This is repeated for two or 
three days, and after they have eaten their fill they are allowed 
to return home. They will soon accustom themselves to under- 
taking the journey on their own account. But they often remain 
away too long, and it is as well to confine this plan to drinking. 
In the evening they are given a very small supply of water, and 
in the morning they are brought a distance of some miles to a 


quiet stream, and put in a basket without a bottom, which is 
allowed to project somewhat into the stream. They soon drink 
their fill and return home. This experiment is repeated for a 
few days, and they will soon be accustomed to seeking the spot 
for themselves in order to satisfy their thirst. If the water is 
near a wood, this has the additional advantage of accustoming 
the pigeons to the sight of the birds of prey, and they thus 
become more likely to recognise and escape them. 

Birds that are intended to be used in balloons must receive 
a special training ; and this can either be done by taking birds 
that have already been trained in the usual way, or by taking 
birds that have had no previous training. It is possible to train 
a bird to return from a balloon in any direction; or, on the 
other hand, birds can be trained to fly in certain directions from 
home. Herr Bernhard Floring of Barmen has for several years 
provided pigeons for the balloons of the Lower Rhine Balloon 
Club ; and he believes that the results did not depend on the 
direction taken by the balloon, though the birds had been trained 
to do their work mainly in certain directions. The performance 
of the pigeons is much affected by the fact that they are always 
obliged to return against the wind, if they are carried in a 
balloon. Ordinarily the birds are not sent out except in fairly 
clear weather, otherwise they are very liable to be lost. But in 
a balloon, little count is taken of such considerations, and conse- 
quently the birds often have to battle against a fairly strong 
wind, and this has the effect of greatly reducing the speed of 
their flight. 

Professor Ziegler of Jena has studied the speed of carrier 
pigeons, particularly with a view to discovering the favourable 
conditions which react on the bird. By comparing the results 
of a large number of experiments, made at the various competi- 
tions, he found that for the longer distances up to, say, 800 miles, 
the average speed is about 20 yards per second. Some birds 
will reach a speed of 86 yards per second, while on other 
occasions, flying against the wind, they will only go at the rate 
of 5 or 6 yards per second; the best pigeons have a mean 
speed of 12 yards per second against a moderate wind. The 



distance from Hanover to Hildesheim lias been used for observa- 
tion purposes ; and it has been found that the journey ia done 
in 15 minutes with the wind, and IJ hours against the wind, 
the total distance being 18^ miles. On another occasion a 
pigeon Hew from a place near Bordeaux to Liege in Belgium, 
and covered 506 miles in 8 hours, but this is a very excepiiooal 
performance. Observations on the flight of migratory birds show 
that they nearly always fly with the wind, and wait till the breeze 
is in their favour before making a 

^— " ^ start. 

I Attempts have also been made 

to use swallows for this purpose. 

^ An Antwerp trainer sent up some 

^B swallows and pigeons at the same 

^^K^. time at Compiegne in France. 

^H|^^ The pigeons covered the distance 

^^^^^^k of 145 miles in S^ hours, while 

^PIH^B^ the swallows arrived in 1 hour 7 

j^jf ^^ minutes ; the speed of the latter 

^^^H|HH|^|HH was therefore three times that 

^^^^^^^^^^^^^^ the former. Two swallows, which 

had been trained at Roulais, were 

started from the Invalides in 

Paris, and reached their home, 

NiU" it.^Mi!^'il" ■ t«ii"nl"»li.'i"'oi"tm^ which was at a distance of 93 

a,.nwmii«oiiUwniui.u™rn8y«. miles, in 75 minutes. It was 

proposed in consequence of this feat to start a training-station 

for swallows in the fort of Mont Valerien. 

Interesting experiments with swallows have been reported in 
the papers from time to time, and the following deserves notice. 
Two swallows had built their nest near the chateau of Nielles- 
les-Ardres in the department of Pas de Calais. A gardener 
caught one of the birds, and took it in a bag to the eihibition in 
Paris. On the next morning it was let loose at 9.80 a.m. at the 
foot of the Eifl'el Tower. It rose up to the first gallery on the 
tower, crossed the Seine, and disappeared in a northerly direc- 
tion without a moment's hesitation. At 11.46 a.m. it reached 

Kia, 220.— Unrk slnw-eciluured a 
rier |iigcon belonging to Hi 


Nielles, and was recognised at once by the red ribbon which was 
tied round its leg. It had covered the distance of 150 miles in 
2 hours 16 minutes. The country must have been strange to the 
bird, because it is hardly likely it would pass over Paris as it 
migrates from Calais to Africa, even supposing it did not go by 
the shortest course. 

As a result of his experiments with balloons, Floring gives the 
following as the mean speeds of the carrier pigeon ; in good 
weather, 26 miles an hour, i.e., 38 ft. per second ; in less favour- 
able weather, 20 miles an hour, i.e., 30 ft. per second ; and in bad 
weather, including rainy, foggy, or snowy days, the speed is only 
15 miles an hour, i.e., 20 ft. per second. Dr. Schultheiss, of 
Garlsruhe, gives rather lower figures. He made eleven experi- 
ments from a balloon in 1895 and found an average speed of 
21 ft. per second. The velocity of the wind on these occasions 
was between 11 and 22 ft. per second. The distances were, of 
course, reckoned in a straight line from start to finish, but 
naturally nothing was known about the actual course. 

The performances of two of Herr Floring's pigeons were 
remarkable. The wind was blowing strongly from the west at 
the rate of 80 ft. per second, and the balloon soon disappeared at 
a height of 650 ft. into the clouds, whence it passed into the rain 
and snow. The first pigeon was released at a height of 3,150ft., 
twenty minutes after the start ; five minutes later, at an altitude 
of 4,100 ft., the second bird was let go. They reached Barmen 
in little more than half an hour, and if allowance is made for 
the speed of the wind, their rates of travelling were about 118 ft. 
per second. On February 1st, 1903, the balloon started from 
Barmen with three birds in a heavy wind ; rain and snow were 
falling at the time. The first bird was let loose about the middle 
of the day, and reached home two days later, having travelled in 
a direct line a distance of about 60 miles. The second bird 
started about 1 p.m., and covered 100 miles in a very heavy 
snowstorm in three days, reaching home completely worn out. 
The third was released at Magdeburg at 8 p.m., and took seven 
wrecks to cover the 185 miles, and reached home after having lost 
three or four of the pinions in each wing, owing to an accident of 



some 8oit. Floriiig's pigeons also performed a feat on the occa- 
sion of a journey wliieh tool; them to a distance of 25 miles from 
Barmen. On landing, they were released and reached home in 
40 minutes, whereas a telegram, announcing their despatch, 
did not arrive till 2^ hours after they were safely in their 

The results of Floring's experiments with balloons and carrier 

Fn!. -22] ,— Hnynau in Silc'sia. Tnken from a height of H.dOO feet, 
pigeons between 1903 and 1906 may be summarised as follows. 
Out of 109 pigeons tliat were released, 103 returned safely ; of the 
remaining six, two were killed by accidents, and the remaining 
four succumbed to the severe cold of winter. The author has 
taken pigeons with him on about 200 ascents, and has released 
about 1,500 birds in all. He has found that Fliiring's estimates 
of speed are fairly correct, and that in foggy and clondy weather 
it often takes more tlian a day to make the return joarney. 
In judging of performances in general, it is necessary to take 


into account the method of training which the birds have under- 
gone. There is a great difference between birds which have been 
well trained in the usual way and are then taken on balloon 
ascents, and others which serve their apprenticeship on a balloon. 
In the latter case a certain number are sure to be lost, and the 
percentage of such losses will probably be rather serious. It is 
also a matter of importance to consider the direction in which the 
balloon has been flying. Often enough birds would fail 
entirely if released on the south side of Berlin at a very 
moderate distance, the wind and weather being favourable. 
They had probably flown often in other directions, but when 
released on the south side their memory seemed to play them 
false. It is therefore necessary to adopt one of two principles ; 
either all the birds must be exercised and trained to fly from any 
direction round the given centre, or the birds can be divided into 
groups, some of which are worked on the north side, others on 
the south, and others again on the east and west. It is generally 
possible to tell the course a balloon will take from observing the 
movements of the clouds ; but at higher levels the breezes may 
blow in other directions, and pigeons intended to work towards 
the south must therefore also be practised somewhat to the east 
and west. 

The time of day at which they are released is a matter of 
importance. If the birds are sent up in the early morning they 
learn a good deal from the position of the sun. Several bal- 
loonists have noticed that a number of birds were lost without any 
very obvious cause, and it was discovered that the result was due 
to the fact that the balloon started at a different time in the day. 
Originally a start was made early in the morning, and the birds 
were released about midday ; but later, the start was deferred, so 
that the birds were only sent on their journey late in the after- 
noon. As it was supposed that they directed their course by the 
position of the sun, they naturally lost their way altogether. 

Better results are obtained if the birds are trained from the 
balloon. It is very essential that they should be accustomed to 
fly at once downwards out of the clouds. For this purpose it is 
well to take them up in a captive balloon, close to their homes, 

A. A A 


and to release them as soon as the clouds are reached, and while 
the earth is still in sight. On another occasion, it may be well 
to penetrate into the clouds, and later on, if the first experiments 
have resulted satisfactorily, to mount above them. The pigeons 
are very much afraid of plunging into a bank of cloud from 
above. Looked at in this way, it strikes them as being some- 
thing new, and altogether outside their experience, and they 
become confused in consequence. They circle around for a long 
time and seem unable to make up their minds; at last when 
they have worn themselves out, they are compelled to descend. 
On a second attempt they appear to understand the situation a 
little better, and they soon learn to find their ways home. The 
intelligence of the pigeons helps them to make use of the sun as 
a guide, in the same way as migratory birds ; but their most 
important organ is the eye. The curvature of the earth is such 
that. at a height of 300 ft., a bird can see about 22 miles ; actually 
the distance is a little greater owing to the effects of atmospheric 

The wind affects them in many ways, partly by reducing the 
speed of their flight, and partly by interfering with their survey 
of the country. A bird soon finds out that the wind generally 
blows more strongly at great altitudes, and therefore flies higher 
if the weather is reasonably calm. Consequently it has a better 
outlook than it would have in rough wind, when it would tend to 
fly closer to the ground. If good results are to be obtained it 
is necessary to pay very careful attention to the pigeons in their 
cots. They consequently enjoy the pleasures of life, and are 
all the more strongly impelled to return. They must also learn 
to regard man with confidence, and it is possible to tell the sort 
of attention they receive from their behaviour to the keeper. 
Their cots must be clean and airy, and they will therefore 
delight to return home. 

There are various artifices by which the performances of the 
birds can be improved, and it is well to know thoroughly the 
habits and peculiarities of all kinds of pigeons. A male pigeon 
returns to the nest as quickly as possible, and the same is true 
of the female bird. The weight of the messages carried by the 



bird is DOt without its effect on its strength, and the mode of 
attaching them to the body is a matter to be studied. The usual 
plan is to write the message on thin paper, and roll it up in a 
rubber covering, fastening it to the feet of the bird. Aluminium 
holders or spring cases are also used, which are fastened under 
the wing, and a great number of similar devices may usually be 

seen at the various shows. Photographs can also be transmitted 
by their means, and this is useful in time of war for the purpose 
of sending plans, etc., from a belenguered town. Experiments of 
this kind were made in St. Petersburg in September, 1889. The 
chief of the Balloon Corps, named Kowanko, made an ascent in 
company with an officer and two others. They then prepared 
photographs on films of collodion according to the wet process. 
The negiitivps were developed in a primitive dark room, which 
was arranged in the basket of the balloon ; the collodion films 


were stripped from the glass, and secured to the birds. The 
results were considered successful. But the preparation of the 
negative in the car of the balloon is a tedious and awkward 
arrangement ; and lately newer methods have been proposed by 
which the undeveloped film is entrusted to the bird and then 
developed at home in more convenient surroundings. 

The carrying power of the birds is considerable, and they have 
been found to be able to carry weights of 2^ ounces to a distance 
of 90 miles. Cages have been built in Warsaw, so that 150 or 
200 birds could be released simultaneously in a besieged fortress 
by means of a balloon. The wicker baskets are put together in 
several sections and supported on the ring of the balloon ; the 
ropes holding the car are longer than usual so that the birds 
do not interfere with the passengers, and the car itself is made 
somewhat broader. The birds are protected from the heat of 
the sun by a covering of oilcloth, which does not shut out the 
light, or bright metallic paper may be used. They have always 
stood the journey well, and the gas, streaming out of the neck, 
does not seem to cause them any inconvenience. They are, 
however, rather liable to be jolted about on landing, and before 
releasing them they must be well fed and have something to 

Various attempts have been made to train the birds to fly to 
a given spot and to return. Captain Malagoli succeeded in doing 
this in Italy, and Hoerter in Germany has trained birds by 
supplying them with water in Hildesheim and with food in 
Hanover. The results were to some extent satisfactory, but this 
method of training has been eventually abandoned. In spite 
of the developments of telegraphy, the use of carrier pigeons for 
collecting information for newspapers still continues. In time 
of war the pigeons form a means of communication which could 
hardly fall into the hands of the enemy, whereas the telegraph 
and telephone might be liable to all sorts of interruption. Duke 
Alexander of Oldenburg, who commanded the Russian Guards, 
trained falcons to hunt the pigeons ; and at distances of two 
miles they did actually succeed in catching them and occasionally 
brought their prey back with them. But of course this kind of 


thing is only worthy of mention as a curious development of 
human activity; as a means of offence the falcon would be bound 
to be a failure. On the other hand, attempts have been made to 
protect the pigeons from birds of prey by fastening small whistles 
to their bodies, but so far from serving its purpose it merely 
attracted attention to the pigeon, and this crude device has met 
with the fate it deserved. 

It is a more difficult matter to prevent the pigeon from being 
snared. On January 28rd, 1871, Gambetta announced special 
punishments for the offence of catching the birds in the following 
terms^ : — 

" In consideration of the importance of the carrier pigeon for 
postal purposes and the defence of the nation, it is hereby 
decreed that anyone killing a dove of any kind during the 
continuation of the war, either by shooting or snaring it or by 
Imnting it in any way whatever, will be liable to six weeks' 
imprisonment. If it can be proved that the bird was killed 
notwithstanding the fact that it was known to be carrying dis- 
patches or to be intended for that purpose, the punishment shall 
be a period of penal servitude, not exceeding five years. Anyone 
giving information leading to a conviction will receive a reward 
between the sums of M2 and i^4, according to the discretion of 

the court. 

" Grbmieux, 

" Minister of the Interior. 
** Bordeaux, January 23re/, 1871." 

Even nowadays, the pigeons are under the protection of the 
authorities, and it is a punishable offence to kill carrier pigeons 
and to keep stray birds that have flown from their cot. Unfortu- 
nately there are many people who snare them on the roofs of 
their houses, and it is quite certain that a large number of carrier 
pigeons are lost by theft every year. 

* See Gross, *' Die Ballon brief tauben post wiihrend der Belagerung von Paris.'* 



Traffic by land and sea is controlled by numberless statutes ; 
but the balloonist has so far escaped legal limitation. It would 
almost appear as though he would be allowed to go on his way 
without let or hindrance ; but many accidents have happened, 
imperilling the lives both of passengers and innocent bystanders, 
and the intervention of the law is bound to come sooner or later. 

In 1902, an international legal congress was held at Brussels, 
when the position of ballooning was discussed. Some of the 
points may be here mentioned, especially seeing that they have 
since been debated at the congress of the Federation Aeronautique 

The first point is as to the distinction to be drawn between 
balloons belonging to the Government of a country and those 
belonging to private individuals. Balloons belonging to the 
State can either be used for military or civil purposes. A 
military balloon is defined as being under the command of an 
oflBcer of the army or navy, who has been entrusted with the 
use of it by the military authorities, the whole of the equipment 
belonging to them. A balloon, belonging to the Government 
and used for civil purposes, must be in charge of an official, 
whose duty it is to make ascents on behalf of the civil authorities. 
All others fall into the category of private balloons, irrespective 
of the standing of the man in charge. 

A balloon ought to be able to be identified in the same way as 
a fillip. Colonel von Kowanko has stated that certain unfortu- 
nate occurrences have taken place owing to the want of an easily 
recognisable signal, such as a flag, denoting the nationality. 
Some Cossacks, stationed on the frontiers, have before now fired 
on German and Austrian balloons. All Russian balloons carry- 
ing passengers have a flag. Any balloon without a flag is 


regarded as being of the nature of a recording balloon, carrying 
meteorological instruments, for the capture of which a reward 
is generally offered, and soldiers are therefore apt to fire on it 
in order to bring it to earth. An accident of this kind is there- 
fore likely enough to happen to any balloon in Russia not 
carrying a flag. 

It was therefore proposed that all balloons, whether belonging 
to private persons or to the government, should carry a flag, 
fastened to the net, half way down the balloon, and that this 
should be easily recognisable both by its shape and colouring. All 
balloons belonging to the Government should fly a pennant, 
which, in the case of military balloons, should be attached to the 
basket, and in the case of civilian balloons, should be attached to 
the envelope immediately beneath the national flag. The shape of 
the flags ought to be distinguishable with the naked eye at a 
distance of 2^ miles. Each balloon ought to carry the colours of its 
own country and of no other, and the man in charge ought to have 
an official certificate, which in the case of private balloons should 
be produced on demand. The qualification of the man in charge 
is a matter of importance. In connection with the army or one 
of the larger clubs, a very thorough training can be had, and 
examinations are held from time to time, as a result of which 
certificates are issued to those whose knowledge appears to be up 
to the mark. The Aero Club of Vienna divides its certificates 
into those of the first and second classes, the higher distinction 
being awarded to the man who is able to manage the balloon 

At the present moment, any professional aeronaut, and indeed 
any amateur, can make an ascent without any restraint, and 
it must be said that in some cases the lack of experience is only 
too evident. Some sort of legislation seems almost necessary to 
prevent accident. A good instance of the preventable accident 
took place last year in Germany. An engineer, named YoUmer, 
made a few ascents, and then announced that he had assumed the 
rdle of a professional balloonist. He found a man in Essen who 
wanted to make an ascent, and they therefore sailed away in 
clear weather and a moderate breeze towards Ostend, where they 


fell into the sea and were drowned. The accident was undoubtedly 
due to the lack of experience on the part of the so-called 
professional aeronaut, whose qualifications had been assumed to 
be satisfactory by his companion without any very thorough 
inquiry. This was clearly a case calling for the interference of 
the authorities. Such men are not only a danger to their 
companions, but to anybody else who comes in their way. Very 
serious accidents may arise owing to explosions if the inflation of 
the balloon is not properly carried out, and, on landing, injuries 
may easily result from unskilful management. It would therefore 
seem to be in the public interest to demand that some sort 
of qualification should be necessary before being allowed to take 
charge of a balloon. 

At the conference at Brussels, the following arrangements 
were proposed. Every private balloon must be registered, and 
have a name and number, which should be printed in large 
letters on the body of the balloon. The place of residence of 
the owner should also be stated, and the number and place of 
origin should be painted in red. Every ascent by a private 
person should be under the control of a State official. Govern- 
ment balloons should not be obliged to carry papers, but private 
balloons must have a copy of the official particulars, and a list 
of the passengers. The flags, etc., must be properly mounted in 
position, a journal must be kept, and the man in charge must 
produce his certificate on demand. Special flags should be 
arranged for signalling that a descent is about to take place 
or that help is needed, which latter would be likely to be speci- 
ally useful if the balloon were to be in danger of being driven 
over the sea. At the congress, a series of regulations were 
drawn up with a view to preventing balloons from passing above 
fortresses. It was proposed that Government balloons should be 
allowed to pass the frontier in case of actual necessity, but that 
a flag should be hung out, showing that help was needed. An 
exception was proposed in the case of Government balloons, 
making ascents for meteorological purposes ; but it seems only 
reasonable that military balloons should not be allowed to cross 
the frontier at will. 



Several other proposals were made with the intention of 
obviating difficulties at the customs, and dealing with other 
cases which might arise. The use of balloons in time of war 
was also discussed, and it seems probable that they will require 
to be regulated in exactly the same way as traffic by sea. The 
question as to the treatment to be meted out to a captured balloon 
is important, considering the important role they may play in 
the future and have, indeed, already played in the past. Soldiers 
are often not available to man the balloon, and it has therefore 
happened that threats have been made to treat captured bal- 
loonists as spies. All regulations which prevent the balloonist 
from acting on the offensive or defensive seem absurd. At the 
Hague Conference it was proposed to forbid the throwing of 
explosives from balloons; but this regulation is no longer in 
force, as it was only valid for a period of five years. Moedebeck 
has pointed out that if the right of attack or defence is taken 
from the balloonist, it is only reasonable to expect that the enemy 
should be prevented from firing on it. 

The proposals of the Brussels Conference may appear to go 
too far from some points of view, but it seems likely that some 
sort of international regulation will be necessary in the future, 
seeing that balloons are now much more common than they 
were, and that the dirigible airship is a practicable possibility. 


Ader, 99 ' 

Aeroplanes, 99 , 

Air-bag, 43, 44, 67, 77 ! 

Aldershot, 139, 164 

/Vlexander, Patrick Y., 117, 250, 253 

/Ups, journeys over the, 226 

Andree, 39 

Anemometer, 69 I 

Antwerp pigeons, 346 

Arago, 246 

Archdeacon, 114 

Aspirator-psychromoter, 246 

Assmann, 198, 242, 246. 250, 258 < 

Astronomical ascents, 280, 281 

Atmosphere, properties of the, 27 

Baden-Powell, 122 

Ballast, 33, 186 

Barometer, 29, 192 

Baro-thermo-hygrograph, 269 

Basket, 185 ! 

Berson, Professor, 199, 215, 270, 271, 


Blanchard, 7, 24, 239 

Brissy, Testu, 184, 239 

Busley, 198, 228 

Camera, 302 

Captive balloon, 187 

Chanute, 109, 113 I 

Charles, 12, 175 

Cocking, 124 I 

Cody, 122 

Colour photography, 330, 332 

Construction of balloon, 17, 175 

Conte, 129, 134 

Coutelle, 128 

Coxwell, 141, 244, 251, 265 

Croc6.Spinelli, 268 

Cylinders, steel, 178 

Dag HON, 286, 344 
Degen, 90 
Deutsch, 70, 89 
Development of plates, 321 
De viators, 212 
Diffusion, 32 
Ducom, 305 
Dumont, Santos, 65, 94 

Eclipse, 281 

Electrical measurements, 279 

Films, 310, 312 
Finsterwalder, 182, 340 
Firing at balloons, 145 
Floring, Bernhard, 349, 351 
Flying machines, 90 
Franklin, Benjamin, 117 

Gambetta, 54, 144, 357 
Garnerin, 22, 124, 197 
Gay-Lussac, 32, 242, 246 
Giddiness, 204 
Giffard, 48, 177 
Glaisher, 243, 265 
Godard, 143, 170 
Goldbeater's skin, 14, 164, 180 
Grapnels, 186 
Green, 124, 179, 211, 242 
Gross, 184, 249, 270 
Guide-rope, 40, 54, 70, 184 
Guy ton de Morveau, 42, 128 

Hagen, 305 
Hergesell, 30, 63, 253 
Hofmann, 104 

Hydrogen, generation of, 19, 20, 
128, 141, 154, 157, 164, 175 

Internatioxal Commission, 253 



Jeffries, 25, 239 
Jourdain, 129 
Juchmes, 77 
JuiUot, 76 

Kite-balloon, 187 
Kites, 116 
Klussmann, 331 
Kowanko, 35o, 358 
Kress, 93, 99 

Landing, 231 
Langley, 97, 102 
Laussedat, 152 
Lavoisier, 128, 177, 239 
L^baudy, 76 
Liege pigeons, 346 
Lift, 31 

Lilienthal, 106 
Long journeys, 199 
Lowe, 139, 285 

Maps, 193 

Marey, 91 

Maxim, Sir Hiram, 97 

May- carp, 116 

Meusnier, 43 

Miethe, 295, 332 

Military ballooning, 128 

Millet, 122 

Moedebeck, 248 

Monaco, Prince of, 71, 93, 263 

Montgolfier, 9 

Naval Ballooning, 155, 167 
Net, 185 

Observatory, 256 
Oxygen, 270, 272 

Panoramic apparatts, 287, 338 
Parachute, 124 
Parseval, Major von, 84, 187 
PhilHps, 96 

Eenard, Captain, 54, 152 
Riedinger, August, 84 
Hipping panel, 183, 195 

Robert, 12, 34, 239 
Robertson, 241 
Rotch, 118, 255, 263 
Rozier de PilAtre, 24 
Rubber balloons, 258 

Sails, 39, 99 

Santos Dumont, 65, 94 

Saussure, 238 

Schroetter, 271 

Schwarz, 58 

Scientific ballooning, 238 

Sea, atmosphere over the, 263 

Sea, journeys over the, 211 

Severe, 58, 73 

Signalling, 120, 135, 139, 160 

Sigsfeld, 35, 59, 187, 198, 202, 206, 

Silberer, Viktor, 166, 279, 288 
Spelterini, 226 
Statoscop'*, 35 
Stentzel, ^2 

Stereoscopic photography, 335 
Suring, 248, 270 

Telephotoscopic lenses, 317 
Teisserenc de Bort, 254, 256, 263 
Templer, 163, 243, 287 
Theory of the balloon, 27 
Tissandier, 53, 144, 148, 252, 268 
Training pigeons, 347 

Valve, 18, 183 

Varnishes, 129, 181 

Vaulx, Coimt de la, 86, 213 

1 Vollbehr, 193 

Voyer, 81 


1 Waggons, military, 154 

; Wellner, 41, 115 

j Welsh, 246 

I Wise, Lieutenant, 121, 184, 242 

I Wright, 110 

. Yon, 50, 143 

I Zambacxjari, 26, 264 
Zeppelin, 61 


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ABBOT, H. L., Gen'l. The Defence of the Seacoast of 

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ber, etc., by automatic and semi-automatic machinery, together 
with the various accessories used in the manipulation of such 
plant, ^so dealing fully with the handling, storing, and ware- 
nousing of grain. With 542 fi^^ures, diagrams, full-page and fold- 
ing plates. Royal Svo, cloth, illustrated. net, $10.00 

ZIPSER. J. Textile Raw Materials, and Their Conversion 

into Yarns. The study of the Raw Materials and the Technology 
of the Spinnini? Process. A Text-book for Textile, Trade and 
higher Technical Schools, as also for self-instruction. Based upon 
the ordinary syllabus and curriculum of the Imperial and Royal 
Weaving Schools. Translated from the German by Chas. Salter. 
Svo, cloth, illustrated net, $5.00 

Catalogue of the Van Nostrand 

Science Series. 

^JTHEY are put up in a uniform, neat, and attractive form. iStno, 
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are amply illustrated when the subject demands. 

R. Armstrong, C.£. Third American Edition. Revised and 
partly rewritten, with an Appendix on "Theory of Chimney 
braught," by F. E. Idell, M.E. 

No. 2. STEAM-BOILER EXPLOSIONS. By Zerah Colbura. New 
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edition, by Prof. W. Cain. 


E. Bender, C.E. Second edition, with Appendix. 

No. 5. VENTILATION OF BUILDINGS. By Wm. G. Snow, S.B., and 
Thos. Nolan, A.M. 

Reservoirs. By Arthur Jacob, B.A. Third American edition, 
revised, with additions by E. Sherman Gould. 


walls. By James S. Tate, C.E. 

John Tumbull, Jr. 2nd edition, revised by Prof. S. W. Robinson. 

No. 9. A TREATISE ON FUEL. By Arthur V. Abbott, C.E. Founded 

on the original treatise of C. WiUiam Siemens, D.C.L. Third ed. 

No. 10. COMPOUND ENGINES. Translated from the French of A. 
Mallet. Second edition, revised with results of American Prac- 
tice, by Richard H. Buel, C.E. 

No. II. THEORY OF ARCHES. By Prof. W. Allan. 

No. 12. THEORY OF VOUSSOIR ARCHES. By Prof. Wm. Cain. 

Third edition, revised and enlarged. 

No. 13.. GASES MET WITH IN COAL MINES. By J. T. Atkinson. 
Third edition, revised and enlaived, to which is added The Action 
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Ho. 14. FRICTION OF AIR IN MINES. By J. J. Atkinson. Second 
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No. 15. SKEW ARCHES. By Prof. E. W. Hyde, C.E. Illustrated. 
Second edition. 

in Arithmetic or A^bra. By Prof. G. L. Vose. Second 

No. 17. WATER AND WATER-SUPPLY. By Prof. W. H. Coifield, 
of the University College, London. Second American edition. 

Baker, Associate Editor "Engineering News.'' Second edition, 
revised and enlarged. 

By Prof. W. Allan, author of "Theory of Arches." Second 
edition, revised. 

No. 20. BRIDGE AND TUNNEL CENTRES. By John B. McMaster, 
C.E. Second edition. 

No. 21. SAFETY VALVES. By Richard H. Buel, C.E. Third edition. 

No. 22. HIGH MASONRY DAMS. By £. Sherman Gould, M. Am. 

Soc. C. E. 

With various Tables of Results and Experiments. From the 
German of I^f. Ludwig Spangenbuig, with a Preface by S. H. 
Shreve, A.M. 

By Prof. S. W. Robinson. 2nd edition, revised, with additions. 

By R. M. Wilcox. 

tinuous Bridges. By Charles Bender, C.E. 

Rowan. Ne-*/ edition. Revised and partly rewritten by F. E. 

W. Stahl, U.S.N. Sccon J edition, revised. 

lated from the French of M. Leon Pochet. 


Magnetism. By Prof. Fairman Rogers. 



Dwelling-houses. By Geoi|^e £. Warixig, Jr. Second edition, 


Hildenbrand, C.E. 

No. 33- MECHANICS OF VENTILATION. By George W. Rafter, CE. 

Second edition, revised. 

No. 34. FOUNDATIONS. By Prof. Jules Gaudard, CE. Trtas- 

lated from the French. Second edition. 

Use. Compiled by George W. Plympton. Ninth edition, 
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No. 36. MATTER AND MOTION. By J. Clerk Maxwell, MJL Second 
American edition. 

and Results. By Frank De Yeaux Carpenter, C.E. 


William Cain, A.M., C.E. New and revised edition. 


graph. By A. E. Loring. Fourth edition, revised. 


Robert Zahner, M.E. New edition, in press. 

No. 41. STRENGTH OF MATERIALS. By WiUiam Kent, C.E., 
Assoc. Eklitor ''Engineering News.'' Second edition. 


Vaulted Structures. By Prof. Wm, Cain. Third edition, 
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No. 43. WAVE AND VORTEX MOTION. By Dr. Thomas Craig, 
of Johns Hopkins University. 

No. 44. TURBINE WHEELS. By Prof. W. P. Trowbridge, Columbia 
College. Second edition. Revised. 

No. 45. THERMO-DYNAMICS. By Prof. H. T. Eddy, UniTersity 

of Cincinnati. New edition, in press. 

No. 46. ICE-MAKING MACHINES. From the French of M. Le Dour. 
Revised b^ Prof. J. E. Denton, D. S. Jacobus, and A. Riesenbeiger. 
Fifth edition, revised. 


Articulated Links. By J. D. C. De Roos. 


By William Cain, C.E. 

No. 49. MOTION OF A SOLID IN A FLUID. By Thomas Craig, Ph.D. 


tion and Arrangemmts. By Prof. W. H. Corfield. 


the Construction of Refracting and Reflecting Teleecopes, with 
a new chapter on the Evolution of the Modem Tdesoope, and a 
Bibliograpnv to date. With diagrams and folding plates. By 
Thomas Nolan. Second edition, revised and enlarged. 


terpretation. Translated from the French of M. Argand by 
Prof. A. S. Hardy. 

Eleventh American edition. 

No. 54. KINEMATICS OF MACHINERY. By Prof. Alex. B. W. 
Kennedy. With an introduction by Prof. R. H. Thurston. 


de Varona. Second edition, revised and enlarged. 

By Benj. Baker, M. Inst., C.E. 

scription of the Edison System. By L. H. Latimer. To 
which is added the Design and Operation of Incandescent Sta- 
tions, by C. J. Field; and the Maximum Efficienc>' of Incandescent 
Lamps, by John W. Howell. 

No. 58. VENTILATION OF COAL MINES. By W. Fairley, M.E., 
and Geo. J. Andr^. 

By S. W. Robinson, C.E. 

By S. W. Robinson, C.E. 

Impurities. By M. N. Baker. Second ed., revised and enlarged. 

No. 62. THEORY OF THE GAS-ENGINE. By Dougald Clerk. Third 
edition. With additional matter. Edited by F. E. Idell, ME. 

P. Gerhard. Tenth edition. 

No. 64. ELECTRO-MAGNETS. By A. N. Mansfield. 


Including Logarithms of Numbers, etc. 

With an Introduction by F. L. Pope. Third edition, revised. 


Discharge through Sewers, Pipes, and Conduits. Based on 
"KuttePs Formula." By P. J. Flynn. 


No. 68. STEAM-HEATING. By Robert Bziggs. Third edition, re- 
vised, with additions by A. R. WolflF. 

No. 69. CHEMICAL PROBLEMS. By Prof. J. C Foye. Fourth 
edition, revised and enlarged. 

No. 70. EXPLOSIVE MATERIALS. By Lieut John P. Wisser. 

No. 71. DYNAMIC ELECTRICITY. By John Hopkinson, J. A. 
Shoolbred, and R. E. Day. 

No. 72. TOPOGRAPHICAL SURVEYING. By George J. Specht. 
Prof. A. S. Hardy, John B. McMaatcr, and H. F. Walling. Third 
edition, revised. 


braic Numbers. By Prof. William Cain. 

tion and Use. By Arthur V. Abbott. 


Being a Supplement to ''Dynamo-electrio Machinery." By 
Prof. Sylvanus P. Thompson. 

Lieut. James S. Pettit, U.S.A. 

No. 77. STADIA SURVEYING. The Theory of SUdia Measure- 
ments. By Arthur Winslow. Sixth editKm. 

W. B. Le Van. 

No. 79. THE FIGURE OF THE EARTH. By Frank C. Roberts, C.E. 


Delivery, etc. Distinctive features of the Worthington, Ken- 
nedy, Siemens, and Hesse meters. By Ross £. Browne. 


septics. By Samuel Bagster Boulton, C.E. 

Shaw, C.E. 

duits, Sewers, etc. With Tables. By P. J. Flynn, C.E. 

No. 8$. THE LUMINIFEROUS iBTHER. By Prof. De Volson Wood. 


scription, and Classification vf Minerals Found in the United 
States. By Prof. J. C. Foye. Fifth edition, revised. 


of Helicoidal Oblique Arches. By John L. Culley, C.E. 

No. 88. BEAMS AND GIRDERS. Practical Formulas for their Resist- 
ance. By P. H. Philbrick. 

erties, and Analyses. By Lieut. John P. Wisser, U^.A. 


By Major J. G. Barnard. 


Spirit. By Prof. I. O. Baker. Second edition. 

Redwood, F.I.C., F.CS. 

Buildings. With Memoranda on the Cost of Phimhing Work. 
Second edition, revised and enlarged. By William Paul Ger- 
hard, C.E. 

No. 94. THE TREATMENT OF SEWAGE. By Dr. C. Meymott 

Fourth edition, revised. 

Assoc. M. Inst., C.E. 


Gerhardi Sanitaiy Engineer. 

to Wind for Any Output. By Frederick Walker. Fully illus* 
trated. Third edition. 

By Prof. Osborne Reynolds. Edited with notes, etc., by F. £. 
Idell, M.E. 

No. zoo. HOW TO BECOME AN ENGINEER; or. The Theoretical 

and Practical Training necessaiy in Fittmg lor the Duties of 
the Qvil Engineer. By Prof. Geo. W. Plympton.^ 

No. xoz. THE SEXTANT, and Other Reflecting Mathematical Instn^ 
ments. With "Practical Hints for thdr Adjustment and Use. 
By F. R. Brainard, U. S. Navy. 

matically By Dr. G. S. Ohm, Berlin, 1827. Translated by 
William Francis. With Preface and Notes by the Editor, Thomas 
D. Lockwood, M.I.E.E. 


Water. With Diagrams. By Geo. W. Rafter. Second edition. 

clmnical Engineers. Compiled by. Prof. Geo. W. Plympton. 

No. Z05. DETERMINANTS. An Introduction to the Study of, with 
Examples and Applications. By Prof. G. A. Miller. 

No. Z06. COMPRESSED AIR. Experiments upon the Transmission of 
Power by Compressed Air m Paris. (Popp'a System.) By 
Prof. A. B. W. Kennedy. The Transmission and Distribution 
of Power trom Central Stations by Compressed Air. By liof. 
W. C. Unwin. Edited by F. E. IdeU. Third edition. 

Rational and Easy Graphical Analysis of the Stresses in Ordinary 
Swing Bridges. With an Introduction on the General Theory 
of Graphical Statics, with Folding Plates. By Benjamin F. 
La Rue. 

No. 108. SLIDE-VALVE DIAGRAMS. A French Method for Con- 
structing Slide-valve Diagrams. By Lloyd Bankson, B.S., 
Assistant Naval Constructor, U. S. Navy. 8 Folding Plates. 

trical Measuring Instruments. By James Swinburne. Meters 
for Electrical Energy. By C. H. Wordingham. Edited, with 
Preface, by T. Commerford Martin. With Folding Plate and 
Niunerous Illustrations. 

No. zzo. TRANSITION CURVES. A Field-book for Engineers, Con- 
taining Rules and Tables for Laying out Transition Curves. By 
Walter G. Fox, C.E. 

No. III. GAS-LIGHTING AND GAS-FITTING. Specifications and 
Rules for Gas-piping. Notes on the Advantages of Gas for 
Cooking and Heating, and Useful Hints to Gas Consumers. Third 
edition. By Wm. Paul Gerhard, C.E. 

No. Z12. A PRIMER ON THE CALCULUS, By E. Sherman Gould, 
M. Am. Soc. C. E. Third edition, revised and enlarged. 

No. Z13. PHYSICAL PROBLEMS and Their Solution. By A. Bour- 
gougnon, formerly Assistant at Bellevue Hospital. Second ed. 

No. 114. MANUAL OF THE SLIDE RULE. By F. A. Halsey, of 
the "American Machinist." Third edition, corrected. 

No. 115. TRAVERSE TABLE. Showing the Difference of Latitude 
and Departure for Distances Between 1 and 100 and for Angles to 
Quarter Degrees Between 1 Degree and 90 Degrees. (Reprinted 
from Seribner's Pocket Ta^ ^ Book.) 


No. zz6. WORM AlTD SPIRAL GEARING. Renrinted from "Ameri- 
can Machinist." By F. A. Halsey. Second revised and enlaiged 

mulas. With Numerous IQustrative figures and Numerical 
Examples. By £. Sherman Gould. 

No. zz8. TREATMENT OF SEPTIC SEWAGE, with Diagnuns and 
Figures. By Geo. W. Rafter. 

Plates and Diamma. By Sanford A. Mcas, M.S , Ph.D Re- 
printed from ''llie American Machinist," with revisions and 
additions. Second edition. 

Ckx>mb8. With Figures, Diagrams and Folding Plates. Re- 
printed from the "American Machinist." 

of Notes accompanying a Course of Lectures delivered at Cornell 
University in 1902. By Sanford A. Moss. Illustrated. 

No. Z22. SHAFT GOVERNORS. By W. Trinks and C. Hoosum. Il- 


Methods. A Handy Reference Book, with figures and tables. By 
William Wallace Christie. Illustrated. 






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