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because its experiments were carried out spasmodically while
dependence was reposed somewhat too much upon foreign effort。
The British airships are small and of low speed comparatively
speaking。 Here again it was the advance of the aeroplane which
was responsible for the manifestation of a somewhat indifferent
if not lethargic feeling towards the airship。 Undoubtedly the
experiments carried out in Great Britain were somewhat
disappointing。 The one and only attempt to out…Zeppelin the
Zeppelin resulted in disaster to the craft before she took to the
air； while the smaller craft carried out upon far less ambitious
lines were not inspiritingly successful。 Latterly the non…rigid
system has been embraced exclusively； the craft being virtually
mechanically driven balloons。 They have proved efficient and
reliable so far as they go； but it is the personal element in
this instance also which has contributed so materially to any
successes achieved with them。
But although Great Britain and France apparently lagged behind
the Germans； appreciable enterprise was manifested in another
direction。 The airship was not absolutely abandoned： vigilance
was maintained for a superior type of craft。 It was an instance
of weighing the advantages against the disadvantages of the
existing types and then evolving for a design which should
possess the former without any of the latter。 This end appears
to be achieved with the Astra type of dirigible； the story of the
development of which offers an interesting chapter in the annals
of aeronautics。
In all lighter…than…air machines the resistance to the air
offered by the suspension ropes is considerable； and the
reduction of this resistance has proved one of the most
perplexing problems in the evolution of the dirigible。 The air
is broken up in such a manner by the ropes that it is converted
into a brake or drag with the inevitable result that the speed
undergoes a severe diminution。 A full…rigged airship such as the
Parseval； for instance； may present a picturesque appearance； but
it is severely unscientific； inasmuch as if it were possible to
eliminateor to reduce the air…resistance offered by the ropes；
the speed efficiency might be raised by some sixty per cent and
that without any augmentation of the propelling effort。 As a
matter of fact Zeppelin solved this vexatious problem
unconsciously。 In his monster craft the resistance to the air is
reduced to a remarkable degree； which explains why these vessels；
despite all their other defects are able to show such a turn of
speed。
It was this feature of the Zeppelin which induced Great Britain
to build the May…fly and which likewise induced the French
Government to stimulate dirigible design and construction among
native manufacturers； at the same time； however； insisting that
such craft should be equal at least in speed to the Zeppelins。
The response to this invitation was the Spiess； which with its
speed of 45 miles per hour ranked； until 1914； as one of the
fastest dirigibles in the French service。
In the meantime a Spanish engineer； Senor Torres； had been
quietly working out a new idea。 He realised the shortcomings of
the prevailing types of airships some eleven years ago； and
unostentatiously and painstakingly set out to eliminate them by
the perfection of a new type of craft。 He perfected his idea；
which was certainly novel； and then sought the assistance of the
Spanish Government。 But his fatherland was not adapted to the
prosecution of the project。 He strove to induce the authorities
to permit even a small vessel to be built； but in vain。 He then
approached the French Astra Company。 His ambition was to build a
vessel as large as the current Zeppelin； merely to emphasise the
value of his improvement upon a sufficiently large scale； and to
enable comparative data concerning the two designs to be
obtained。 But the bogey of expense at first proved insuperable。
However； the French company； decided to give the invention a
trial； and to this end a small 〃vedette〃 of about 53；000 cubic
feet displacement was built。
Although an unpretentious little vessel； it certainly served to
emphasise the importance of the Torres idea。 It was pitted
against the 〃Colonel Renard；〃 the finest ship at that time in the
French aerial service； which had proved the fastest airship in
commission； and which also was a product of the Astra Company。
But this fine craft was completely outclassed by the puny
Astra…Torres。
The builders and the inventor were now additionally anxious
to illustrate more emphatically the features of this design and
to build a far larger vessel。 The opportunity was offered by the
British Government； which had been following the experiments with
the small Astra…Torres in France。 An order was given for a
vessel of 282；500 cubic feet displacement； in this instance it
was ranged against another formidable rivalthe Parseval。 But
the latter also failed to hold its own against the Spanish
invention； inasmuch as the Astra…Torres built for the British
authorities exceeded a speed of 50 miles per hour in the official
tests。 This vessel is still doing valuable duty； being attached
to the British air…service in France。
The achievements of the British vessel were not lost upon the
French Government； which forthwith placed an order for a huge
vessel of 812；200 cubic feet capacity； equipped with motors
developing 1；000 horse…power； which it was confidently expected
would enable a speed of 60 miles per hour to be attained。 Thus
France would be able to meet the Germans upon fairly level terms；
inasmuch as the speed of the latest Zeppelins does not exceed 60
miles per hour。 So confident were the authorities that a second
order for an even larger vessel was placed before the first large
craft was completed。
This latter vessel is larger than any Zeppelin yet built； seeing
that it displaces 38 tons； and is fitted with motors developing
1；000 horse…power。 It has recently been completed； and although
the results of the trials； as well as the dimensions of the craft
have not been published； it is well known that the speed has
exceeded 60 miles per hour； so that France now possesses the
speediest dirigible in the world。
The Torres invention has been described as wonderful；
scientifically perfect and extremely simple。 The vessel belongs
to the non…rigid class； but the whole of the suspension system is
placed within the gas…bag； so that the air…resistance offered by
ropes is virtually eliminated in its entirety； for the simple
reason that practically no ropes are placed outside the envelope。
The general principle of design may be gathered from the
accompanying diagram。 It is as if three sausage…shaped balloons
were disposed pyramidallytwo lying side by side with one
super…imposed； with the bags connected at the points where the
circular sections come into contact。 Thus the external