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[The Blog of Phileas Fogg: 1883 onwards] September 29th 1884

From: Harry Hayfield <harryhayfield~at~googlemail.com>
Date: Sat, 11 Jul 2009 13:47:21 -0700 (PDT)
To: jvf~at~gilead.org.il

It's been almost 40 years since I was last at school, but that's
precisely where myself, Passepartout and Mr. Barbicane went this
afternoon in order to get a basic understanding of what we hope to do
on October 4th and our teacher was none other than the science adviser
brought in by the President who announced himself as Professor Smith of
the University of New York

"Good afternoon, Professor Smith!" we all chorused and then laughed.

Professor Smith was going to give us a run down of the basics of
getting something into the air and asked Mr. Barbicane what he knew
about explosives.

"I'm the king of them!" he replied and gave us a resume of the research
up to this moment in time. It is generally asserted that gunpowder was
invented in the fourteenth century by the monk Schwartz, who paid for
his grand discovery with his life. It is, however, pretty well proved
that this story ought to be ranked among the legends of the middle
ages. Gunpowder was not invented by any one; it was the
lineal successor of the Greek fire, which, like itself, was composed of
sulphur and saltpeter. A litre of gunpowder weighs about two pounds;
during combustion it produces 400 litres of gas. This gas, on being
liberated and acted upon by temperature raised to 2,400 degrees,
occupies a space of 4,000 litres: consequently the volume of powder is
to the volume of gas produced by its combustion as 1 to 4,000. One may
judge, therefore, of the tremendous pressure on this gas when
compressed within a space 4,000 times too confined.

"I understand that" I said, "but fail to see how it helps us!"

"It's the amount of force" explained Professor Smith, "that will
determine how fast the Columbiad goes and it is the speed that will
determine the success of this mission!"

Seeing as both myself and Passepartout has blank faces, the Professor
took a stick of chalk and started to draw on the blackboard.

"Let us assume that you have a cannon on top of a hill and you fire a
cannonball. The cannonball will be moved forwards by the force of the
gunpowder, however at the same time it will fall towards the ground.
With me so far?" asked the Professor and we both nodded.

"Now, point that cannon straight up and you find that the cannonball
would instead of travelling forwards go straight up until as such time
the force of gravity would equal the force of the gunpowder at which
point it would start to fall down, now, if you are able to increase the
upwards force so that it is able to escape the pull of gravity it is
possible to launch something into space!"

"Ah" I said, "that's the calculation that the observatory at Cambridge
came up with" and referred to my previous entry on the subject. "Here
we are I said, 1,200 yards per second"

At this the Professor stared at me and started to laugh his head off.

"I'm sorry, have I said something hilarious?" I asked

"2,467 miles per hour?" the Professor said, trying hard to keep a
straight face. "You seriously expect to launch that thing into space at
a mere 2,500 mph??? Dear me, I knew that Victorian Earth was dim but
this is ridiculous!!!"

I looked at the Professor and then at Mr. Barbicane and Passepartout
who both shrugged their shoulders. After a while the Professor calmed
down and looked at the three of us.

"Try nearer 17,000 mph!" he said

"How fast?" we all exclaimed

"It's like this" the Professor explained, "At that speed, the Columbiad
will still fall towards the Earth but miss everytime and go into what
is known as orbit. If the long term aim is to reach the moon you then
have to increase the speed again to a little over 25,000 mph in order
to reach a higher orbit and then hope that you get attracted by the
moon. At that point you can either slow down a bit and go into orbit
around the moon or wait until you fly past the Earth again and then
slow down in order to land again. Got that?"

I could see that Barbicane was staggering to understand all this and
being American I half expected his next comment.

"Are you trying to tell me that Cambridge Observatory have been feeding
me bad figures?" he exploded

"Not bad" replied the Professor, "just ill informed". He opened a bag
that he had brought in with him and handed Barbicane a sheet with a
list on it. "There you go" he said, "the complete list of ingredients
needed to create a big enough bang in order to send your Columbiad into
space and round the moon all calculated for the weight of the three of
you combined all down to the nearest ounce!"

No sooner had Barbicane been handed the list than he dashed out of the
school room and was seen heading for the telegraph office at full pelt.
I raised my hand and the Professor asked if something was the matter.

"Is the class dismissed?" I asked

"Correctamundo!" replied the Professor "A word I have uttered only once
and vowed never to do so again" he said as he bowed and left the room
leaving me and Passepartout slightly suprised

--
Posted By Harry Hayfield to The Blog of Phileas Fogg: 1883 onwards on
7/11/2009 09:46:00 PM

Received on Sat 11 Jul 2009 - 23:47:32 IDT

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