- Appleton, Victor.
Tom Swift and His Airship.
Bedford, MA: Applewood Books, [1910] 1992. ISBN 1-55709-177-3.
-
Following his adventures on
land and
lake,
in this third volume of the Tom Swift series, our hero takes to the air in his
hybrid dirigible/airplane, the Red Cloud. (When this book was written,
within a decade of the Wright Brothers' first flight, “airship”
referred to any flying craft, lighter or heavier than air.) Along the
way he survives a forest fire, thunderstorm, flying bullets, false accusation of
a crime, and an irritable schoolmarm not amused by having an airship crash into
her girls' school, and solves the crime, bags the perpetrators, and clears his
good name. Bless my seltzer bottle—never get on the wrong side of Mr. Wakefield
Damon!
Apart from the arm-waving about new inventions which is the
prerogative of the science fiction writer, Victor Appleton is
generally quite careful about the technical details—All
American Boys in the early 20th century knew their machinery and
would be all over a scribbler who didn't understand how a
carburetor worked! Here, however, he misunderstands lighter
than air flight. He describes the Red Cloud as
supported by a rigid aluminium gas container filled with
“a secret gas, made partly of hydrogen, being very light and powerful”.
But since the only thing that matters in generating lift is the
weight of the air displaced compared to the weight of the gas
displacing it, and since hydrogen is the lightest of elements
(can't have fewer than one proton, mate!), then any mixture of
hydrogen with anything else would have less lift than
hydrogen alone. (You might mix hydrogen with helium to obtain a
nonflammable gas lighter than pure helium—something suggested by
Arthur C. Clarke a few years ago—but here Tom's secret gas is
claimed to have more lift than hydrogen, and the question
of flammability is never raised. Also, the gas is produced on
demand by a “gas generator”. That rules out helium as a component,
as it is far too noble to form compounds.) Later, Tom increases the
lift on the ship by raising the pressure in the gas cells: “when an
increased pressure of the vapor was used the ship was almost as
buoyant as before” (chapter 21). But increasing the pressure of
any gas in a fixed volume cell reduces the lift, as
it increases the weight of the gas within without displacing any
additional air. One could make this work by assuming a gas cell
with a flexible bladder which permitted the volume occupied by
the lift gas to expand and contract as desired, the rest being filled with
ambient air, but even then the pressure of the lift gas would not
increase, but simply stay the same as atmospheric pressure as more
air was displaced. Feel free to berate me for belabouring such a
minor technical quibble in a 95 year old story, but I figure that
Tom Swift fans probably, like myself, enjoy working out this kind of
stuff. The fact that this is only such item I noticed is
a testament to the extent Appleton sweated the details.
I read the electronic edition of this novel published
in the
Tom Swift and His Pocket
Library
collection at this site on my PalmOS PDA in random moments of
downtime over a month or so. I've posted an updated electronic
edition which corrects typographical errors I spotted while reading
the yarn.
June 2005 