ncement,
steady, 4 lbs. 1/2 oz., 57 revolutions to 1 oz. water, steam cut off
one-third from beginning.
'The diameter of cylinder of engine was 1 1/2 inch, length of stroke 3
inches.
'In the meantime an engine was also made for the smaller model, and a
wing action tried, but with poor results. The time was mostly devoted to
the larger model, and in 1847 a tent was erected on Bala Down, about two
miles from Chard, and the model taken up one night by the workmen. The
experiments were not so favourable as was expected. The machine could
not support itself for any distance, but, when launched off, gradually
descended, although the power and surface should have been ample;
indeed, according to latest calculations, the thrust should have carried
more than three times the weight, for there was a thrust of 5 lbs. from
the propellers, and a surface of over 70 square feet to sustain under 30
lbs., but necessary speed was lacking.'
Stringfellow himself explained the failure as follows:--
'There stood our aerial protegee in all her purity--too delicate, too
fragile, too beautiful for this rough world; at least those were
my ideas at the time, but little did I think how soon it was to be
realised. I soon found, before I had time to introduce the spark, a
drooping in the wings, a flagging in all the parts. In less than ten
minutes the machine was saturated with wet from a deposit of dew, so
that anything like a trial was impossible by night. I did not consider
we could get the silk tight and rigid enough. Indeed, the framework
altogether was too weak. The steam-engine was the best part. Our want of
success was not for want of power or sustaining surface, but for want of
proper adaptation of the means to the end of the various parts.'
Henson, who had spent a considerable amount of money in these
experimental constructions, consoled himself for failure by venturing
into matrimony; in 1849 he went to America, leaving Stringfellow to
continue experimenting alone. From 1846 to 1848 Stringfellow worked on
what is really an epoch-making item in the history of aeronautics--the
first engine-driven aeroplane which actually flew. The machine in
question had a 10 foot span, and was 2 ft. across in the widest part of
the wing; the length of tail was 3 ft. 6 ins., and the span of tail in
the widest part 22 ins., the total sustaining area being about 14
sq. ft. The motive power consisted of an engine with a cylinder of
three-quarter inch
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