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Book
I
/
AIRSHIPS PAST AND PRESENT
AIRSHIPS PAST AND
PRESENT
TOGETHER WITH CHAPTERS ON THE USE
OF BALLOONS IN CONNECTION WITH
METEOROLOGY, PHOTOGRAPHY AND THE
CARRIER PIGEON
A. HILDEBRANDT
Captain and iBtlruclar in tht Pruiiian BmUobh Carps
TRjm SLATED BY W. H. STOJIT
NEW YORK
D. VAN NOSTRAND COMPANY
1] MURRAY AND 17 WARREN STREETS
^
\^
0^
BRADBUKY, AONKW, & CO. LD., FK1NTKR8,
LONDON AND TONBRIDOB.
/ '-yt'-'V
V5
o
PREFACE.
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
forthcoming.
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
vi PEEFACE.
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
meteorologists.
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.
PBEFACE. vii
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.
CONTENTS.
CHAPTBB PAGE
I. THB BARLY HISTORY OF THE ART 1
n. THE INVENTION OF THE AIR BALLOON 9
m. MONTOOLFIERES, CHARLI^RES, AND ROZIERES . . . .14
lY. THE THEORY OF THE BALLOON 27
V. THE DEVELOPMENT OF THE DIRIGIBLE BALLOON ... 88
VI. THE HISTORY OF THE DIRIGIBLE BALLOON, 1852 — 1872 . . 48
VII. DIRIGIBLE BALLOONS FROM 1888 — 1897 58
vm. „ „ „ 1898—1906 61
IX. FLYING MACHINES 90
X. KITES 116
XI. PARACHUTES 124
Xn. THE DEVELOPMENT OF MILITARY BALLOONING .... 128
Xm. BALLOONING IN THE FRANCO-PRUSSIAN WAR .... 141
XIV. MODERN ORGANISATION OF MILITARY BALLOONING IN FRANCE,
GERMANY, ENGLAND, AND RUSSIA 151
XV. MILITARY BALLOONING IN OTHER COUNTRIES .... 169
XVI. BALLOON CONSTRUCTION AND THE PREPARATION OF THE GAS . 175
XVn. INSTRUMENTS 192
XVm. BALLOONING AS A SPORT 197
XIX. SCIENTIFIC BALLOONING 288
XX. BALLOON PHOTOGRAPHY 284
XXI. PHOTOGRAPHIC OUTFIT FOR BALLOON WORK .... 802
XXII. THE INTERPRETATION OF PHOTOGRAPHS . 828
XXni. PHOTOGRAPHY BY MEANS OF KITES AND ROCKETS . 887
XXIV. PROBLEMS IN PERSPECTIVE 840
XXV. CARRIER PIGEONS FOR BALLOONS 848
XXVI. BALLOON LAW 858
IKDBX 868
LIST OF ILLUSTRATIONS.
no. PAOE
1. THE THBONE OF XERXES DRAWN THROUGH THE AIR BT FOUR TAME
EAGLES 2
2. FAUSTE YERANZIO IN HIS PARACHUTE 3
3. THE FLTINO SHIP, DESIGNED BY FRANCISCO DE LAN A ... 4
4. PHOTOGRAPH OF AUGSBURG, SHOWING THE CATHEDRAL. TAKEN
FROM A BALLOON BY A. RIEDINGEE 5
5. MEERWEIN'S FLYING MACHINE. FROM MOBDEBECK'B " POCKET BOOK
FOR BALL00NI8T8 '* 7
6. CLOUDS PHOTOGRAPHED FROM A BALLOON 10
7. ASCENT OF A " MONTOOLFI^RE " 11
8. PORTJENGRAT, AN ALPINE PEAK. PHOTOGRAPH BY 8PBLTERINI 15
9. A SUCCESSFUL LANDING 16
10. APPARATUS FOR GENERATING HYDROGEN 20
11. PARIS, SHOWING THE EIFFEL TOWER ...... 21
12. A BALLOON IN THE ACT OF LANDING 23
IS. THE " ROZI^BB,*' CONSTRUCTED BY PIlItRE DE ROZIER ... 24
14. THE BAROSCOPE 28
15. VIENNA. PHOTOGRAPH TAKEN FROM A CAPTIVE BALLOON 29
16. STOCKHOLM, SEEN FROM A HEIGHT OP 1,600 FEET . . . . 31
17. THE STATOSCOPE, BY GRADENWITZ 35
18. A PARADE ON THE TEMPELHOFER FELD 36
19. BALLOON WITH SAIL, AND WITH GUIDE-ROPE 40
20. SCOTT'S FISH BALLOON 41
21. BALLOON, DESIGNED BY GENERAL MEUSNIER 4.')
22. GIFFARD*S DIRIGIBLE BALLOON, MADE IN 1852 .... 48
23. GIFFARD'S SECOND BALLOON, MADE IN 1855 50
24. DUPUY DE Lome's balloon, 1872 51
25. PAUL HAENLEIN'S DIRIGIBLE BALLOON 52
26. THE BASKET OP TISSANDIER'S DIRIGIBLE BALLOON .... 53
27. TISSANDIER'S DIRIGIBLE BALLOON 54
28. THE BALLOON ^' LA FRANCE," BUILT BY RKNARD AND KREBS . 56
29. CAPTAIN RENARD 57
30. DR. WbLFERT'S DIRIGIBLE BALLOON ABOUT TO START 58
31. SCHWARZ'S BALLOON AFTER THE ACCIDENT 59
32. COUNT ZEPPELIN'S DIRIGIBLE BALLOON ()2
33. COUNT ZEPPELIN 63
34. SANTOS DUMONT (56
35. SANTOS DUMONT'B SECOND BALLOON BREAKS ITR BACK, MAY llTH,
JlOvV ...I .■••.... t)|
A. b
Xll
LIST OF ILLUSTRATIONS.
FIO.
36. SANTOS DUMONT'S THIRD BALLOON
37. GRADENWITZ ANEMOMETER
38. rozb's double balloon
39. SBVERO'S BALLOON ABOUT TO START
40. FRAMEWORK AND CAR OP L^BAUDY'S DIRIGIBLE BALLOON
41. CAR OP L^BAUDY's balloon
42. l^baudy's dirigible balloon
43. MAJOR PARSEVAL'S DIRIGIBLE BALLOON ....
44. COUNT DK LA VAULX
45. COUNT DE LA. VAULX'S DIRIGIBLE BALLOON
46. DBGBN'S flying MACHINE
47. DIAGRAMS ILLUSTRATING MARBYN THEORY WITH REFERKNCE TO
THE FLIGHT OF A BIRD ....
48. STENTZEL'S FLYING MACHINE
49. DUFAUX* FLYING MACHINE WITH PROPELLERS
50. SANTOS DUMONT'S FIRST FLYING MACHINE
51. PHILLIPS' FLYING MACHINE
52. SIR HIRAM MAXIM'S FLYING MACHINE
63, ADER'S PLYING MACHINE ....
54. KRESS'S FLYING MACHINE ....
65. DITTO ........
56. STARTING ARRANGEMENTS FOR PROFESSOR LANGLEY*S PLYING
MACHINE
57. PROFESSOR LANGLEY'S FLYING MACHINE AT THE MOMENT OF
STARTING
58. HOFMANN'S first MODEL WITH CARBONIC ACID MOTOR
59. HOFMANN'S WORKING MODEL
60. HERR HOFMANN AND MR. PATRICK ALEXANDER IN THE WORKSHOP
61. LILIENTHAL ON HIS FLYING MACHINE
62. LILIENTHAL STARTING FROM THE HILL ON HIS FLYING MACHINE
63. STARTING AN AEROPLANE
64. AEROPLANE IN FLIGHT
65. ARCHDEACON'S EXPERIMENTS ON THE SEINE
66. LANGLEY'S FLYING MACHINE ON THE POTOMAC
i\7. WBLLNER'S FLYING MACHINE
68. THE JAPANESE " MAY CARP " .
69. HARGRAVE KITE
70. OTHER SHAPES OF HARGRAVE KITES .
71. VARIOUS FORMS OF KITES .
72. CODY'S KITE
73. CODY'S KITE USED AS A CAPTIVE BALLOON
74. KITE FOR SIGNALLING
76. SIGNALLING BY MEANS OP LIGHTS FROM A KITE
76. LIEUTENANT WISE MAKING AN ASCENT IN A KITE
77. millet's kite CARRYING OBSERVERS
PAGE
68
69
72
75
78
79
81
85
.86
87
90
91
92
94
95
97
98
99
100
101
103
104
105
105
106
107
108
110
111
113
114
115
116
117
117
118
119
120
121
121
122
123
LIST OP ILLUSTRATIONS. xiii
*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
99. BARRACKS FOR THE PRUSSIAN BALLOON CORPS AT TEGEL .163
100. A COLLECTION OF EXPLODED GAS CYLINDERS 164
101. CAPTAIN HINTEltSTOISSER, OF THE AUSTRIAN BALLOON CORPS 166
102. AFTER A LANDING 171
103. A BALLOON READY FOB INFLATION .173
104. ASCENT OF A CAPTIVE BALLOON IN CALM WEATHER .176
105. ASCENT OF A CAPTIVE BALLOON ON A WINDY DAY .177
106. STEEL CYLINDER FOR CONTAINING HYDROGEN 179
107. SECTION THROUGH STEEL CYLINDER 179
108. MAKING BALLOON ENVELOPES IN REI DINGER'S FACTORY . .181
109. PROFESSOR FINSTERWALDER'S PATTERNS FOR BALLOON ENVELOPES 182
110. BALLOON VALVES 183
HI. THE FIRST RIPPING-PANEL USED IN A BALLOON IN 1844 185
112. ARRANGEMENTS FOR RIPPING-PANEL 185
113. NET OF A BALLOON 186
114. DIFFERENT KINDS OF GRAPNEL 186
115. -THE KITE-BALLOON DESIGNED BY MAJOR VON PARSE VAL AND
CAPTAIN VON SIOSPBLD 187
116a. DITTO 188
XIV
LIST OF ILLUSTRATIONS.
FIG. PAQS
116. DRAWING SHOWING THE DESIGN OF THE KITE-BALLOON 189
117. BASKET SUSPENSION 190
118. ANEROID BAROMETER . 192
119. BAROGRAPH, OR RECORDING BAROMETER 193
120. BALLOON BASKET AND ITS CONTENTS 194
121. VOLLBEHR'S MICROPHOTOSCOPE 194
122. MICROPHOTOSCOPE IN CASE 195
123. MICROPHOTOSCOPE, WITH MAGNIFYING GLASS FOR USE IN DAYLIGHT 195
124. PROFESSOR BUSLEY, PRESIDENT OF THE BERLIN BALLOON CLUB 199
125. A BANK OF CLOUDS 201
126. BALLOON AFTER THE RIPPING-CORD HAS BEEN PULLED . . 202
127. THE HOFBURG, VIENNA 203
128. HELIGOLAND 205
129. WATER ANCHOR FOR BALLOON 209
130. BALLOON EXPEDITIONS ACROSS THE ENGLISH CHANNEL . .211
131. COUNT DE LA VAULX' BALLOON OVER THE MEDITERRANEAN . . 212
132. BASKET OF COUNT DE LA VAULX' BALLOON 212
133. COUNT DE LA VAULX* DBVIATOR IN ACTION 213
134. DEVIATOR OFFERING THE MAXIMUM RESISTANCE .... 214
135. DEVIATOR OFFERING THE MINIMUM RESISTANCE .... 215
136. MAP SHOWING THE COURSE OF THE BALLOON FROM BERLIN TO
MARKARYD 216
137. CURVE GIVEN BY THE RECORDING BAROMETER ON THE JOURNEY
FROM BERLIN TO MARKARYD 217
138. STOCKHOLM SEEN FROM AN ALTITUDE OF 3,000 FEET .221
139. MISCHABELHORN, SEEN FROM THE EAST 222
140. THE LAKE OF LUCERNE 227
141. BALLOON AND BALLOONISTS ON THEIR WAY HOME .... 229
142. LANDING IN A TREE 231
143. DILLINGEN, SEEN THROUGH THE CLOUDS 232
144. BUILDING A PONTOON OVER ^HE SPREE 235
145. BRIDGE OVER THE ILLER, NEAR KEMPTEN 236
146. DR. JEFFRIES WITH THE BAROMETER USED ON HIS ASCENTS . . 240
147. APPARATUS FOR GENERATING HYDROGEN 241
148. GLAISHER AND COXWELL IN THE BASKET 244
149. GLAISHER'S INSTRUMENTS 245
150. BASKET FITTED WITH INSTRUMENTS ACCORDING TO THE METHOD
PROPOSED BY A8SMANN 247
151. ASSMANN'S ASPIRATOR-PSYCHROMETER . 248
152. PROFESSOR ASSMANN AND PROFESSOR BERSON 249
153. THE KAISER ATTENDING THE ASCENT OF A RECORDING BALLOON
ON THE TEMPELHOFER FELD, NEAR BERLIN .... 251
154. MAJOR MOEDEBECK 252
155. CAPTAIN VON SIG8FELD 252
156. CAPTAIN GROSS 253
157. A RECORDING BALLOON WITH INSTRUMENTS 254
LIST OF ILLUSTRATIONS. xv
no. PAGE
158. A WICKRRWORK BASKET WITH INSTRUMENTS FOB A RECORDING
BALLOON 255
159. DR. HEROESBLL 256
160. ASCENT OP A BALLOON, FITTED WITH A PARACHUTE, AT LINDENBERG 257
161. ASCENT OF A BOX KITE CONTAINING METEOROLOGICAL INSTRUMENTS 258
162. WINCH HOUSE AT ASSMANN'S AERONAUTICAL OBSERVATORY . . 269
. 261
. 262
. 261
. 265
. 266
KITE
. 267
. 269
. 270
163. CURVK8 TAKEN BY RECORDING INSTRUMENTS .
164. CURVES GIVEN BY RECORDING INSTRUMENTS
165. A. LAURENCE ROTCH
166. KITE ASCENTS ON THE PRINCE OF MONACO'S YACHT
167. RECORDING BALLOONS ON THE 88. "PLANET" .
168. THE AMERICAN METEOROLOGIST, ROTCH, MAKING SOME
ASCENTS ON THE ATLANTIC
169. BARO-THKRMO-HYGROGRAPH, DESIGNED FOR BALLOONS
170. BARO-THERMO-HYGROGRAPH, DESIGNED FOR KITES .
171. BARO-THERMO-HYGROGRAPH, DESIGNED FOR RECORDING BALLOONS 271
172. PROFESSOR StjRING, OF THE PRUSSIAN METEOROLOGICAL INSTITUTE 272
173. THE BALLOON, "PRUSSIA," BELONGING TO THE AERONAUTICAL
OBSERVATORY 273
174. HERR VON SCHROBTTER'S ORDINARY HANDWRITING .... 274
175. HERR VON SCHROETTER'S HANDWRITING UNDER AN ATMOSPHERIC
PRESSURE OF 9*45 INCHES OF MERCURY 275
176. THE BALLOON, *' PRUSSIA," HALF FULL OF GAS .... 276
177. THE BALLOON, "PRUSSIA," GETTING READY FOR AN ASCENT . . 277
178. VIKTOR SILBERER, PRESIDENT OF THE AERO CLUB, OF VIENNA . 279
179. THE SHADOW OF THE BALLOON IS SEEN ON THE CLOUDS, TOGETHER
WITH A HALO 280
180. THE SHADOW OF THE BALLOON M^CAST ON THE CLOUDS, AND THE
CAR IS SEEN SURROUNDED BY A RAINBOW 281
181. TRIBOULET'S PANORAMIC APPARATUS 288
182. THE FIRST PHOTOGRAPH TAKEN FROM A BALLOON IN AUSTRIA . 289
183. THE REICHSBRUCKE IN VIENNA . 290
184. EASTERN RAILWAY STATION IN BUDAPESTH 294
185. CLOUDS OVER THE ALPS 298
186. PHOTOGRAPH OP A VILLAGE 299
187. PHOTOGRAPH OF A VILLAGE, TAKEN AT NIGHT .... 300
188. DUCOM'S PHOTOGRAPHIC APPARATUS 304
189. HAGEN'S METHOD OF MOUNTING THE CAMERA 304
190. PHOTOGRAPH OF THE EXHIBITION BUILDINGS . . . 806
191. BARON VON BASSUS' RIFLE APPARATUS 308
192. VAUTIER-DUFOUR APPARATUS, PACKED IN ITS CASE . . . 309
193. VAUTIKR-DUPOUR APPARATUS, READY FOR USE 309
194. AIGUILLE VERTE, TAKEN WITH THE VAUTIER-DUFOUR APPARATUS 310
195. AIGUILLE VERTE, TAKEN WITH AN ORDINARY LENS .311
196. FILM HOLDER 312
4
xvi LIST OF ILLUSTRATIONS.
»'I0 PAGE
197. DIAGRAM SHOWING THE RELATION BETWEEN THE FOCAL LENGTH
OF THE LENS, THE SIZE OF THE IMAGE, AND THE DISTANCE OP
THE OBJECT 317
198. MONT BLANC, AS SEEN FROM GENEVA . itee facing jtoge 317
199. DITTO see facing page 317
200. PYRAMIDS OF CHEOPS, CHEPHREN, AND MENCHERES . 318
201. CAPTAIN SPELTKRINI, OF ZURICH 320
202. VILLAGE IN POSEN, AS SEEN FROM A BALLOON IN WINTER . . 323
203. HERRENBERG IN WURTTEMBURG 324
^\'-T . .............. 32o
206. VIEW OF BLANKENBURG IN THE HARZ MOUNTAINS . 326
20(i. RUDERSDORF 327
207. CHALKPITS NEAR RUDERSDORF 328
208. VILLAGE IN THE UCKERMABK IN WINTER 329
209. OBJECTS OF DIFFERENT COLOURS, PHOTOGRAPHED FROM ABOVE 330
210 DITTO 331
211. CAMERA FOR THREE-COLOUR PHOTOGRAPHY 332
212. SLIDING SCREEN CARRIER FOR THREE-COLOUR PHOTOGRAPHY . . 333
213. MIETHK^S CAMERA FOR THREE-COLOUR PHOTOGRAPHY IN A BALLOON 334
214. BOULADE'S STEREOSCOPIC CAMERA 336
216. BATUT'S kite for PHOTOGRAPHIC APPARATUS .... 388
216. PANQHAMIC APPARATUS FOR A BALLOON WITHOUT OBSERVERS . 338
217. THE VILLAGE OF RUDOW, AS SHOWN ON THE ORDNANCE MAP . 340
218. PHOTOGRAPH OF RUDOW, TAKEN FROM A BALLOON .341
219. PHOTOGRAPHIC REPRODUCTION OF MESSAGES ON A REDUCED SCALE 346
220. DARK SLATE-COLOURED CARRIER PIGEON BELONGING TO HERR
FLORING 350
221. HAYNAU IN SILESIA. TAKEN FROM A HEIGHT OF 8,000 FEET . 362
222. IN THIS PHOTOGRAPH THE SHADOW OF THE BALLOON IS SEEN ON
THE OLD FORTIFICATIONS 355
AIRSHIPS PAST AND PRESENT
CHAPTER I.
THE EARLY HISTOBY OF THE ART.
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
/
AIRSHIPS PAST AND PRESENT.
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
Montgolfier,
Francisco de Lana sliowed great ingenuity in his contrivance
I'iG. 1. — The throDe of Xerxes drawn
through Ibe air b; four tame eaglea.
THE EARLY HISTORY OP THE ART.
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.
4 AIRSHIPS PAST AND PBESENT.
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
THE EARLY HISTOEY OP THE ART. 5
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
6 AIESHIPS PAST AND PRESENT.
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
subtleties.
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
THE EARLY HISTORY OF THE ART. 7
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
8 AlESHIPS PAST AND PEESENT.
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.
CHAPTER II.
THE INVENTION OF THE AIR BALLOON.
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
10
AIRSHIPS PAST AND PRESENT.
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
THE INVENTION OF THE AIR BALLOON.
11
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
12 AIRSHIPS PAST AND PRESENT.
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.
THE INVENTION OP THE AIR BALLOON. 18
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.
CHAPTER III.
MONTOOLFIERES, CHAKLIERES, AND ROZI^RES.
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
MONTGOLFlfeRES, CHARLIERE8, AND ROZIEUES. 16
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
friends.
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
16 AIRSHIPS PAST AND PRESENT.
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
MONTGOLFIERES, CHARLIERES, AND ROZIERES. 17
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.
40
008
80
0074
0006
120
0069
0011
160
0*064
0016
200
006
002
212
0-059
0021
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
A.
c
18 AIESHIPS PAST AND PRESENT,
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.
MONTGOLFIERES, CHARLIERES, AND ROZIERES. 19
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
MONTGOLEIEEES, CHARLIERES, AND ROZlfiRES. 21
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.
22 AIRSHIPS PAST AND PEESENT.
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
MONTGOLFlfeRES, CHAELlfiRES, AND ROZlfiRES. 23
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
T
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.
24
AIRSHIPS PAST AND PRESENT.
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
bimiiltaneoiisly.
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
MONTGOLFIERES, CHARLlfiRES, AND ROZIERES. 25
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
20 AIRSHIPS PAST AND PRESENT.
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.
CHAPTER IV.
THE THEORY OF THE BALLOON.
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
AIRSHIPS PAST AND PRESENT.
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
•V
THE THEORY OF THE BALLOON. 29
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
80 AIRSHIPS PAST AND PRESENT.
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
THE THEORY OP THE BALLOON. 31
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
82 AIRSHIPS PAST AND PRESENT.
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.
\
THE THEORY OF THE BALLOON. 88
bnt a little experience is far more useful than any amount of
calculation.
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
84 AIRSHIPS PAST AND PRESENT.
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
\
THE THEORY OF THE BALLOON. 35
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
AIRSHIPS PAST AND PUESEST.
THE THEOKY OF THE BALLOON. 87
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.
CHAPTEE V.
THE 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
^
DEVELOPMENT OF THE DIRIGIBLE BALLOON. 89
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
AIESHIPS PAST AND PBEBENT.
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
DEVELOPMENT OF THE DIRIGIBLE BALLOON. 41
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
achieved.
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
42 AIRSHIPS PAST AND PRESENT.
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
DEVELOPMENT OF THE DIRIGIBLE BALLOON. 43
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
44 AIESHIPS PAST AND PEESENT.
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
DEVELOPMENT OF THE DIRIGIBLE BALLOON. 46
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
46 AIRSHIPS PAST AND PRESENT.
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-
struction.
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
earth.
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
DEVELOPMENT OF THE DIRIGIBLE BALLOON. 47
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.
CHAPTER VI.
THE HISTORY OF THE DIRIGIBLE BALLOON FROM 1852 TO 1872.
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
1852.
\
THE HISTORY OF THE DIRIGIBLE BALLOON. 49
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
50 AIRSHIPS PAST AND PRESENT.
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
THE HISTORY OF THE DIRIGIBLE BALLOON. 51
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
52
AIRSHIPS PAST AND PRESENT.
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.
CHAPTER VII.
DIRiaiBLB BALLOONS FROM 188S TO 1897.
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
54
AIRSHIPS PAST AND PRESENT.
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
DIRIGIBLE BALLOONS FROM 1888 TO 1897. 55
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
£6
AIRSHIPS PAST AND PRESENT.
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
DIRIGIBLE BALLOONS FROM 1888 TO 1897. 57
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
unsuccessful.
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
58
AIRSHIPS PAST AND PRESENT.
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
DIEIG-IBLE BALLOONS FROM 1883 TO 18tf7. 59
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
60 AIRSHIPS PAST AND PRESENT.
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.
CHAPTER VIII.
DIRIGIBLE BALLOONS FROM 1898 TO 1906.
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
62
AIRSHIPS PAST AND PRESENT.
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.
DIRIGIBLE BALLOONS FIIOM 1898 TO 1906. 63
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.
64 AIRSHIPS PAST AND PRESENT.
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
DIRIGIBLE BALLOONS FROM 1898 TO 1906. 65
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.
t
bic
o
i
1^
Number.
Shape.
G^
•-"$
a
ti
Motor.
i
¥
1
1
Cylindrical ; conical
6,350
82
t
11-5
I.
3 h.p. Dion •
at back and front.
Bouton.
II.
ditto.
7,060
82
12-5
ditto.
III.
Cigar-shaped.
Filled with coal
gas.
17,650
66
24-6
ditto.
IV.
Cylindrical : conical
at back and front.
14,800
95
16-7
7 h.p. Buchet.
V.
ditto. 1 19,400
108
16-4
12 h.p. with four
cylinders.
VI.
Elongated ellipsoid.
22,200
108
19-7
ditto.
Winner of the
1
Deutsch Prize.
VII.
ditto. 44,600
1
r
164
26-25
60 h.p., weigh ing^
2\ cwt.
VIII.
(Sold to an American ; only made <
)ne trip.)
IX.
Egg-shaped. | 7,770
60
18
3 h.p. Clement.
" The Balladeuse."
1
(26 Ibe.)
X.
Ellipsoidal.
71,000
157
27-9
20 h.p.
" The Omnibus."
XI.
ditto.
42,400
111
16 h.p. with four
cylinders.
(3i cwt.)
XII.
(Placed at disposal of military auth
lorities.)
XIII.
Egg-shaped.
C7,100
62
47-7
XIV.
Cigar-shaped.
6,670
134
111
15 h.p. Peugeot.
1
(57 lbs.)
A.
F
66
AIRSHIPS PAST AND PRESENT.
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.
DIEIGIBLE BALLOONS FROM 1898 TO 1906. 67
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
68
AIRSHIPS PAST AND PRESENT.
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.
DIRIGIBLE BALLOONS FROM 1898 TO 1906. 69
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.
70 AIRSHIPS PAST AND PRESENT.
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
ballast.
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
DIRIGIBLE BALLOONS FROM 1898 TO 1906. 71
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
72 AIRSHIPS PAST AND PRESENT.
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
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
formed.
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
DIRIGIBLE BALLOONS FROM 1898 TO 1906. 73
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.
74 AIRSHIPS PAST AND PRESENT.
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
t*
TVi.
_j^
B
5
W^
V^
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
76 AIRSHIPS PAST AND PRESENT.
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.
DIRIGIBLE BALLOONS FROM 1898 TO 1906. 77
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
78 AIRSHIPS PAST AND PRESENT.
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
DIRIGIBLE BALLOONS FROM 1898 TO 1906. 79
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,'
80 AIRSHIPS PAST AND PRESENT.
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
DIRIGIBLE BALLOONS FBOM 1898 TO 1906. 81
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.
82 AIRSHIPS PAST AND PRESENT.
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
DIRIGIBLE BALLOONS FROM 181J8 TO 1906. 83
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
84 AIRSHIPS PAST AND PRESENT.
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
DIRIGIBLE BALLOONS FROM 1898 TO 1906. 85
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
86 AIRSHIPS PAST AND PRESENT.
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
€8
3
bo
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X
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73
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88 AIRSHIPS PAST AND PRESENT.
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.
DIKIGIBLE BALLOONS PKOM 1898 TO 1906. 89
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CHAPTER IX.
FLYINO UACHINES.
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
FLYING MACHINES. 91
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
B
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
92 AIRSHIPS PAST AND PEESENT.
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
FLYING MACHINES. 98
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
94
AIRSHIPS PAST AND PRESENT.
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
FLYING MACHINES.
95
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.
r-.r-x<s«jssi5«^
sj^sW(H,^>^v.:-.
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
motion.
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
96 AIRSHIPS PAST AND PRESENT.
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
FLYING MACHINES.
97.
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
AIRSHIPS PAST AND PRESENT.
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
FLYING MACHINES. 99
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
100
AIRSHIPS PAST AND PRESENT.
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
FLYING MACHINES.
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
102 AIKSHIPS PAST AND PRESENT.
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
tubes.
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
FLYING MACHINES.
lOS
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
104
AIRSHIPS PAST AND PRESENT.
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
FLYING MACHINES.
105
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
106
AIRSHIPS PAST AND PRESENT.
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.
PLYING MACHINES. 107
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
108 AIRSHIPS PAST AND PBESENT.
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
FLYING MACHINES. 109
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
110
AIRSHIPS PAST AND PRESENT.
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.
FLYING MACHINES. Ill
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
112 AIBSHIPS PAST AND PKESENT.
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
^
FLYING MACHINES.
113
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
114
AIRSHIPS PAST AND PRESENT.
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
FLYING MACHINES. 115
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
balloon.
1
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.
KITES.
117
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.
118 AIRSHIPS PAST AND PRESENT.
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
KITES.
119
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
120
AIRSHIPS PAST AND PRESENT.
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.
KITES.
121
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
elgDalliDg.
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
122
AIRSHIPS PAST AND PRESENT.
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
making
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.
KITES.
128
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.
CHAPTER XI.
PARACHUTES.
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
PARACHUTES. 125
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
Y'
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
126
AIRSHIPS PAST AND PRESENT.
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
parachute.
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
PARACHUTES.
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.
I
I
I
CHAPTER XII.
THE DEVELOPMENT OF MILITARY BALLOONING.
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
\
DEVELOPMENT OP MILITARY BALLOONING. 129
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.
130 AIRSHIPS PAST AND PRESENT.
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
DEVELOPMENT OF MILITARY BALLOONING. 131
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
132 AIRSHIPS PAST AND PRESENT.
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
DEVELOPMENT OF MILITARY BALLOONING. 133
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
134 - AIRSHIPS PAST AND PRESENT.
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
DEVELOPMENT OF MILITARY BALLOONING. 135
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.
136 AIRSHIPS PAST AND PRESENT.
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
DEVELOPMENT OF MILITARY BALLOONING. 137
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,
138 AIRSHIPS PAST AND PRESENT.
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
DEVELOPMENT OF MILITARY BALLOONING. 139
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
140 AIRSHIPS PAST AND PRESENT.
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.
CHAPTER XIII.
BALLOONING IN THE FBANGO-PBUSSUN WAB.
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.
142
AIRSHIPS PAST AND PRESENT.
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
BALLOONING IN THE FRANCO-PRUSSIAN WAR. 148
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
144 AIRSHIPS PAST AND PRESENT.
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
BALLOONING IN THE FRANCO-PRUSSIAN WAR. 145
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,
146 AIRSHIPS PAST AND PRESENT..
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
yards.
A diameter of 4*4 yards corresponds to a distance of 4,000
yards.
A diameter of 5*5 yards corresponds to a distance of 5,000
yards.
A diameter of 6*6 yards corresponds to a distance of 6,000
yards.
A diameter of 11 yards corresponds to a distance of 10,000
yards.
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
guns.
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.
BALLOONING IN THE FRANCO-PRUSSIAN WAR. 147
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
possible.
(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.
148 AIRSHIPS PAST AND PRESENT.
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
BALLOONING IN THE PHANCO-PBUSSIAN WAR. 149
I I
I I
8 I
160 AIRSHIPS PAST AND PBESENT.
'* 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
arrangements.
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
disbanded.
CHAPTER XIV.
MODBRN ORGANISATION OF MILITABT BALLOONING IN FRANCE,
QBRMANT, BNOLAND, AND RU8SU.
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.
162
AIBSHIPS PAST AND PRESENT.
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
contusions.
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
ORGANISATION OF MILITARY BALLOONING. 158
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.
154
AIRSHIPS PAST AND PRESENT.
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
ORGANISATION OP MILITARY BALLOONING. 155
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
1
'f
Fig. 94.— French method ol
■uapending Ihe basket for
Ml obaerver.
156 ■ AIRSHIPS PAST AND -PRESENT.
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
ORGANISATION OF MILITARY BALLOONING. 157
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-
ply.
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
158 AIRSHIPS PAST AND PRESENT.
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
ORGANISATION OP MILITARY BALLOONING. 159
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.")
160 AIRSHIPS PAST AND PRESENT.
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
ORGANISATION OF MILITARY BALLOONING. 161
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
162 AIKSHIPS PAST AND PKESENT.
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.
England.
Experiments with captive balloons were made in England in
1862. A military school for ballooning was started at Chatham
ORGANISATION OF MILITARY BALLOONING. 168
in 1879 under Cnptain Templer, and in the following year the
24th company of the Royal Engineers waB instructed in the
H 2
164 AIRSHIPS PAST AND PRESENT.
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
ORGANISATION OP MILITARY BALLOONING. 165
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.
Austria.
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
166
AIRSHIPS PAST AND PRESENT.
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
ORGANISATION OP MILITARY BALLOONING. 167
arise in time of war, recourse would probably be had to the Aero
Club, of which Silberer is president.
Russia.
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
Finland.
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
168 AIRSHIPS PAST AND PRESENT.
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.
CHAPTER XV.
MILITARY BALLOONING IN OTHER COUNTRIES.
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
170 AIRSHIPS PAST AND PRESENT.
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
matter.
In 1885 a complete ballooning outfit was ordered by the
MILITARY BALLOONING IN OTHER COUNTRIES. 171
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
adopted.
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
172 AIRSHIPS PAST AND PRESENT.
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
army.
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
MILITAEY BALLOONING IN OTHER COUNTRIES. 173
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^
174 AIRSHIPS PAST AND PRESENT.
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.
CHAPTER XVI.
BALLOON CONSTRUCTION AND THE PREPARATION OF THE GAS.
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
176
AIRSHIPS PAST AND PRESENT.
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
BALLOON CONSTRUCTION, ETC.
177
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
Iptivpbftlind
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
178 AIRSHIPS PAST AND PRESENT.
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
BALLOON CONSTRUCTION, ETC. 179
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
180 AIRSHIPS PAST AND PRESENT.
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
BALLOON CONSTRUCTION, ETC.
181
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
Augsburg.
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
182
AIRSHIPS PAST AND PRESENT.
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
envelopes.
BALLOON CONSTRUCTION, ETC.
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
184 AIESHIPS PAST AND PEESENT.
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.
BALLOON CONSTRUCTION, ETC.
185
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. ")
186
AIRSHIPS PAST AND PRESENT.
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
balloon.
(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.
BALLOON CONSTRUCTION, ETC.
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
188 AIRSHIPS PAST AND PRESENT.
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.!.
BALLOON CONSTRUCTION, ETC.
189
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
190
AIRSHIPS PAST AND PRESENT.
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
BALLOON CONSTRUCTION, ETC. 191
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.
CHAPTER XVII.
Ih STRUM EHT5.
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-
meter.
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
INSTRUMENTS. 198
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
194
AIRSHIPS PAST AND PRESENT.
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
INSTRUMENTS.
195
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
196 AIRSHIPS PAST AND PRESENT.
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.
CHAPTER XVIII.
BALLOONING AS A SPORT.
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
discredit.
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
198 AIRSHIPS PAST AND PRESENT.
" 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
experiments.
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
chapter.
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.
BALLOONING AS A SPORT.
199
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,
200 AIESHIPS PAST AND PEESENT.
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
case.
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
BALLOONING AS A SPORT. 201
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
202 AIRSHIPS PAST AND PRESENT.
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
BALLOONING AS A SPORT. 208
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.
204 AIRSHIPS PAST AND PRESENT.
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
BALLOONING A3 A SPORT.
T
Ci 7
'S '' ,,
i
"I
noting the time which it takes to reach places on the map, bnt
an experienced balloonist can generally make a fairly accurate
206 AIRSHIPS PAST AND PRESENT.
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
BALLOONING AS A SPORT. 207
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.
208 AIRSHIPS PAST AND PRESENT.
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
V
BALLOONING AS A SPORT.
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
chattels.
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.")
210 AIRSHIPS PAST AND PRESENT.
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
\
BALLOONING AS A SPORT.
211
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
212 AIRSHIPS PAST AND PRESENT.
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
BALLOONING AS A SPORT.
213
" 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
214
AIRSHIPS PAST AND PRESENT.
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
V
BALLOONING AS A 8P0BT.
215
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
216
AIRSHIPS PAST AND PRESENT.
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
BALLOONING AS A SPORT.
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
gftIJi"
218 AIRSHIPS PAST AND PRESENT.
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
\
BALLOONING AS A SPORT. 219
\^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
220 AIRSHIPS PAST AND PRESENT.
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
late.
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
w
BALLOONING AS A. 8P0RT.
221
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.)
We
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
222 AIRSHIPS PAST AND PRESENT.
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.
BALLOONING AS A SPORT. 223
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
224 AIRSHIPS PAST AND PRESENT.
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.
^
BALLOONING AS A SPORT. 225
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
226 AIKSHIPS PAST AND PBESENT.
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
importance.
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,
4
BALLOONING AS A SPOKT. 227
if not three, passengers ; consequently this woald require a
balloon of 70,000 cabic feet capacity, wbicb muBt be filled with
hydrogen.
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
228 AIRSHIPS PAST AND PRESENT.
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
BALLOONING AS A SPORT. 229
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
230 AIBSHIPS PAST AND PEESENT.
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,
BALLOONING AS A SPOBT. 281
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
232 AIRSHIPS PAST AND PRESENT.
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
J
BALLOONING AS A SPORT. 288
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
234 AIESHIPS PAST AND PRESENT.
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
BALLOONING AK A SPORT. 235
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
236 AIRSHIPS PAST AND PRESENT.
evident that v/e were going at a breakneck speed to the
ground.
" 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
BALLOONING AS A SPOET. 237
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.
CHAPTER XIX.
SCIENTIFIC BALLOONING.
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
applied.
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.
SCIENTIFIC BALLOONING.
239
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
electricity.
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: —
Time.
Temperature
Fahrenheit.
Barometer
in inches.
Uydro-
meter.
Altitude in
feet above
sea level.
Rate of
ascent in feet
per second.
liate of change
of temperature
per 100 feet.
Remarks.
2.20
2.45
3.3
61
40
35
30-0
270
250
3
262
2,880
4,850
1-64
1-83
-0-42
-0-254
cloudy
cloudy
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
240
AIRSHIPS PAST AND PEESENT.
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
SCIENTIFIC BALLOONING.
241
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.
242 AIRSHIPS PAST AND PRESENT.
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
SCIENTIFIC BALLOONING. 243
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
244 AIRSHIPS PAST AND PEESENT.
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
SCIENTIFIC BALLOONING.
245
of India. At these heights the readings of the psychrometer to
be carefully compared with thoee of Daniell's and Begnault's
hygrometers.
(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
atmosphere.
(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
^l^ff
>. 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
246 AIRSHIPS PAST AND PRESENT.
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.
SCIENTIFIC BALLOONING. 247
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
248
AIRSHIPS PAST AND PRESENT.
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.
SCIENTIFIC BALLOONING 249
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
260 AIRSHIPS PAST AND PEE SENT.
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
SCIENTIFIC BALLOONING. 251
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
^ ^
Jl_^^
— 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.
252
AIESHIPS PAST AND PEESENT.
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
radiation.
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
Sigsfeld.
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
SCIENTIFIC BALLOONING. 253
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.
254 AIRSHIPS PAST AND PRESENT.
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
SCIENTIFIC BALLOONING.
considerable differences of temperature. This layer-formation
is one o( the most important subjects at present under
investigation.
" 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.
256
AIRSHIPS PAST AND PRESENT.
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
experience.
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
SCIENTIFIC BALLOONING.
257
" 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
258
AIBSHIPS PAST AND PRESENT.
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
SCIENTIFIC BALLOONING. 259
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
L4J
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
260 AIESHIPS PAST AND PRESENT.
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
Ik
SCIENTIFIC BALLOONING. 261
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
meteorologists.
262 AIRSHIPS PAST AND PRESENT.
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
\
SCIENTIFIC BALLOONING. 268
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,
2G4 AIRSHIPS PAST AND PRESENT.
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
supposed.
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
. SCIENTIFIC BALLOONING. 265
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
2(i6
AlESHIPS PAST AND PRESENT.
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
SCIENTIFIC BALLOONING. 267
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."
268 AIRSHIPS PAST AND PRESENT.
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,
SCIENTIFIC BALLOONING. 269
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.
270
AIHSHIPS PAST AND PRESENT.
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
SCIENTIFIC BALLOONING.
271
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
Strassburg.
272
AIRSHIPS PAST. AND PRESENT.
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
SCIENTIFIC BALLOONING.
273
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
274
AIRSHIPS PAST AND PRESENT.
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.
SCIENTIFIC BALLOONING. 275
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
276
AIRSHIPS PAST AND PRESENT.
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
SCIENTIFIC BALLOONING.
277
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,
278 AIRSHIPS PAST AND PRESENT.
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
SCIENTIFIC BALLOONING.
279
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,
280
•AIRSHIPS PAST AND PRESENT.
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
SCIENTIFIC BALLOONING.
281
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.
282 AIRSHIPS PAST AND PRESENT.
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
SCIENTIFIC BALLOONING. 283
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.
CHAPTER XX.
BALLOON PHOTOGRAPHY.
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
BALLOON PHOTOGRAPHY. 285
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
286 AIRSHIPS PAST AND PRESENT.
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
isai^Hi»
BALLOON PHOTOGRAPHY. 287
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
288 AIRSHIPS PAST AND PBESENT.
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
favourable.
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
acquitted.
Balloon photography has received much assistance from the
BALLOON PHOTOGRAPHY. 289
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
AIRSHIPS PAST AND PRESENT.
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
BALLOON PHOTOGRAPHY. 291
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
292
AIRSHIPS PAST AND PRESENT.
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.
100
500
1,000
Speed of the object in feet per second.
3
6
15
SO
001
0-05
0-1
0-02
t)-0.>
001
001
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
BALLOON PHOTOGRAPHY. 293
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
294 AIRSHIPS PAST AND PRESENT.
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
BALLOON PHOTOGRAPHY. 296
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
296 AIRSHIPS PAST AND PBESENT.
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
BALLOON PHOTOGRAPHY.
297
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
Zenith
65^ W.
1
2
6
3
Condition of the Sky.
bloe
glijfhtly cloudy -
half covered -
overcaet
heavy clouds -
_ 1 I
1
1-5
2
3
()
Aperture.
16
298 AIRSHIPS PAST AND PRESENT.
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.
BALLOON PHOTOGRAPHY. 299
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
800 AIKSHIPS PAST AND PKESENT.
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
BALLOON PHOTOGRAPHY. 801
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.
CHAPTER XXL
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
\
PHOTOGRAPHIC OUTFIT FOR BALLOON WORK. 303
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
304
AIRSHIPS PAST AND PRESENT.
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
apparatus.
(From Plulgliellla " Hsndbooli for
constantly shifting load. This plan has therefore been
abandoned.
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
PHOTOGRAPHIC OUTFIT FOR BALLOON WORK. 305
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
impracticable.
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
306 AIRSHIPS PAST AND PRESENT.
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.
PHOTOGRAPHIC OUTFIT FOR BALLOON WORK. 307
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
308 AIRSHIPS PAST AND PRESENT.
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.
V
packed in ilg
PHOTOGRAPHIC OUTFIT FOR BALLOON WORK. 309
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.
Plate-holders.
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
310
AIRSHIPS PAST AND PRESENT.
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
Jtfl
ifflB
fiG. 191.— Aiguille Verte, taktn with the
Vantier-Dufour appanitiu by the Vega
Company, of Gene»ft.
s
PHOTOGRAPHIC OUTFIT FOB BALLOON WORK. 311
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-
cluded.
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.
Plates.
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
Geaeva.
812 AIESHIPS PAST AND PEESENT.
But in balloon work, certain plates muBt be used iF good reeults
are to be obtained, though doubtleee there is a certain latitude
allowable.
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
PHOTOGRAPHIC OUTFIT FOR BALLOON WORK. 813
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.
314 AIRSHIPS PAST AND PRESENT.
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
\
PHOTOGRAPHIC OUTFIT FOR BALLOON WORK. 815
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
816 AIRSHIPS PAST AND PRESENT.
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 . ' -
57?^-
-
A »- ^ ' ^
■
^^^■B?^''~nh«teW
"•"--"-1
1
■
■
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.
PHOTOGRAPHIC OUTFIT FOR BALLOON WORK. 317
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.
318
AIESHIPS PAST AND PRESENT.
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,
PHOTOGRAPHIC OUTFIT FOR BALLOON WORK. 319
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.
320 AIBSHIPS PAST AND PRESENT.
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-
weight.
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
PHOTOGRAPHIC OUTFIT FOR BALLOON WORK. 821
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
requires.
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
322 AIRSHIPS PAST AND PRESENT.
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.
CHAPTER XXII.
THE INTERPRETATION OF PHOTOGRAPHS.
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
-Village
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
324 AIRSHIPS PAST AND PEESENT.
is pointed directly downwards. It is therefore well to say a
few words about the means that exist for interpreting balloon
photographs.
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 IJJTERPRETATION OF PHOTOGRAPHS. 825
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
AIRSHIPS PAST AND PRESENT.
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
THE INTERPRETATION OF PHOTOGRAPHS. 327
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
AIESHIPS PAST AND PBESENT.
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
THE INTERPRETATION OF PHOTOGRAPHS. 329
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.
830 AIESHIPS PAST AND PEE SENT.
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
THE INTERPRETATION OF PHOTOGRAPHS. 331
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
832
AIESHIPS PAST AND PRESENT.
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
THE INTEEPRETATION OF PHOTOGRAPHS. S33
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.
334 AIRSHIPS PAST AND PRESENT.
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
THE INTEEPEETATION OF PHOTOGEAPHS. 835
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
886
AIESHIPS PAST AND PEESENT.
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.
CHAPTER XXIII.
PHOTOGRAPHY BY MEANS OF KITES AND ROCKETS.
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
338 AIESHIPS PAST AND PRESENT.
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
apparatus.
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
PHOTOGEAPHY BY MEANS OF KITES & EOCKETS. 889
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
CHAPTER XXIV.
PROBLEMS IN PBR8PECTIVB.
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
842 AIESHIPS PAST AND PEESENT.
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.
CHAPTEE XXV.
CARRIEB PIGEONS FOR BALLOONS.
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
344 AIRSHIPS PAST AND PEESENT.
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
CARRIER PIGEONS FOB BALLOONS. 345
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
346 AIRSHIPS PAST AND PRESENT.
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
CABRIER PIGEONS FOR BALLOONS. 847
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
home.
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
348 AIESHIPS PAST AND PRESENT.
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
CARRIER PIGEONS FOR BALLOONS. 349
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
350
AIRSHIPS PAST AND PRESENT.
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
CAEEIEE PIGEONS FOE BALLOONS. 351
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
352
AIRSHIPS PAST AND PRESENT.
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
cots.
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
CAERIER PIGEONS FOR BALLOONS. 358
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
364 AIBSHIPS PAST AND PRESENT.
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
refraction.
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
CARBIEB PIGEONS FOR BALLOONS.
S55
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
856 AIESHIPS PAST AND PRESENT.
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
drink.
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
CARRIER PIGEONS FOR BALLOONS. 857
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.'*
CHAPTER XXVI.
BALLOON LAW.
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
Internationale.
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
BALLOON LAW. 859
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
single-handed.
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
860 AIRSHIPS PAST AND PRESENT.
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.
BALLOON LAW.
361
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.
INDEX.
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,
281
Blanchard, 7, 24, 239
Brissy, Testu, 184, 239
Busley, 198, 228
I
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
864
INDEX.
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,
248
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
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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William Francis. With Preface and Notes by the Editor, Thomas
D. Lockwood, M.I.E.E.
D. VAN N08TRAND COMPANY'S
No. Z03. THE MICROSCOPICAL EXAMINATIOH OF POTABLE
Water. With Diagrams. By Geo. W. Rafter. Second edition.
No. Z04. VAN NOSTRAND'S TABLE-BOOK FOR CIVIL AND M£-
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No. Z05. DETERMINANTS. An Introduction to the Study of, with
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No. Z06. COMPRESSED AIR. Experiments upon the Transmission of
Power by Compressed Air m Paris. (Popp'a System.) By
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of Power trom Central Stations by Compressed Air. By liof.
W. C. Unwin. Edited by F. E. IdeU. Third edition.
No. 107. A GRAPHICAL METHOD FOR SWING BRIDGES. A
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La Rue.
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Niunerous Illustrations.
No. zzo. TRANSITION CURVES. A Field-book for Engineers, Con-
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No. III. GAS-LIGHTING AND GAS-FITTING. Specifications and
Rules for Gas-piping. Notes on the Advantages of Gas for
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No. Z12. A PRIMER ON THE CALCULUS, By E. Sherman Gould,
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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
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No. ZZ7. PRACTICAL HYDROSTATICS, AND HYDROSTATIC FOR-
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No. Z2Z. ELEMENTS OF GAS ENGINE DESIGN. Reprint of a Set
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University in 1902. By Sanford A. Moss. Illustrated.
No. Z22. SHAFT GOVERNORS. By W. Trinks and C. Hoosum. Il-
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