Authors: Erik Larson
Men
understood
the
hazards
of
hurricanes,
but
the
fundamental
engines
that
drove
such
weather
continued
to
elude
them.
Where
did
wind
come
from?
And
what
gave
it
such
power?
By
the
early
eighteenth
century
important
pieces
of
the
puzzle
were
in
place.
Air
pressure
could
be
measured,
even
at
sea.
Temperature
scales
at
last
allowed
precise
comparisons
of
hot
and
cold.
The
most
important
piece,
however,
lay
unrecognized,
even
though
the
underlying
principle
had
been
proven
long
before.
IN
1627,
A
very
brave
if
melodramatic
German
mathematician,
Joseph
Furtenbach,
aimed
a
loaded
cannon
into
the
sky
in
preparation
for
an
experiment
he
hoped
would
provide
the
first
real-world
test
of
another
of
Galileo's
theories:
that
the
earth
rotated
on
a
fixed
axis.
This
was
high-wire
science.
If
Galileo
was
right
—
and
Furtenbach
fervently
hoped
he
was
—
a
cannon
ball
fired
straight
into
the
sky
would
fall
back
to
earth
somewhere
to
the
west
of
the
cannon,
while
the
earth's
rotation
carried
Furtenbach
safely
east.
If
Galileo
was
wrong,
the
ball
would
fall
to
earth
exactly
at
the
point
where
it
rose
from
the
cannon,
and
Furtenbach
would
be
dead.
He
fired
the
cannon.
As
the
ball
soared
into
the
sky,
he
hurried
to
the
muzzle
and
sat
on
it.
Skeptics
in
the
audience
no
doubt
stepped
back
a
respectful
distance,
wary
not
only
of
the
descending
ball
but
also
of
the
likely
splash
of
viscera.
How
the
seconds
must
have
dragged
as
that
ball
whined
into
its
descent,
the
smile
on
Furtenbach's
face
growing
fixed,
the
more
squeamish
members
of
the
audience
raising
their
hands
to
cover
their
eyes
but
peeking
of
course
through
the
latticework
of
fingers...
Thwump.
Silence.
Furtenbach
slid
from
the
muzzle,
his
head
and
smile
intact.
To
the
west
—
a
small
crater.
Proof
at
last.
The
earth
did
spin.
It
was
Edmund
Halley,
of
comet
fame,
who
recognized
that
this
rotation
might
have
a
powerful
effect
on
the
earth's
weather.
Seeking
to
explain
the
trade
winds,
Halley
argued
that
the
sun's
rays
fell
most
consistently
upon
the
equator.
As
the
sun
moved
over
the
earth,
it
caused
successive
parcels
of
air
to
rise.
Other,
cooler
air
rushed
in
to
fill
the
space
and
followed
the
sun
around
the
globe
in
a
steady
rush
of
wind.
A
compelling
theory,
but
it
had
a
significant
hole:
It
could
not
explain
why
the
prevailing
easterlies
of
the
trade
belt
suddenly
gave
way
north
of
the
Horse
Latitudes
to
winds
blowing
in
exactly
the
opposite
direction.
What
Halley
failed
to
take
into
account
was
the
shape
of
the
earth:
the
fact
that
the
world
moves
more
slowly
in
New
York
City
—
although
no
New
Yorker
would
ever
concede
it
—
than
in
Key
West.
In
1735,
George
Hadley,
often
confused
with
Halley,
crafted
an
explanation
of
the
trades
that
was
so
compellingly
simple
it
remained
the
accepted
theory
even
through
Isaac
Cline's
Saturday.
HADLEY
RECOGNIZED
THAT
an
object
anchored
near
the
north
pole
and
another
near
the
equator
traveled
through
space
at
different
speeds:
Both
objects,
being
attached
to
the
same
planet,
had
to
complete
one
rotation
within
the
same
period
of
time,
but
the
object
at
the
equator
had
to
cover
a
much
greater
distance
and
therefore
had
to
move
a
lot
faster.
The
air
at
each
location,
Hadley
saw,
also
moved
at
these
differing
velocities.
He
agreed
with
Halley
that
as
the
sun
heated
the
equator,
it
caused
air
to
rise,
and
cooler
air
flowed
in
to
take
its
place.
But
Hadley
proposed
that
the
cool
replacement
air
would
retain
its
polar
velocity.
The
farther
south
it
went,
the
slower
it
would
seem
to
travel
relative
to
the
ground
below.
Anyone
encountering
this
slow-moving
mass
of
air
would
experience
it
as
a
wind
that
veered
to
the
right
of
its
direction,
or
toward
the
west.
These
were
the
trade
winds.
Conversely,
Hadley
saw,
air
migrating
north
would
seem
to
accelerate
relative
to
the
ground.
As
it
cooled,
it
would
descend
but
retain
its
faster
equatorial
speed.
Observers
on
the
ground
would
perceive
this
as
a
wind
blowing
toward
the
east,
or
veering
to
the
right
of
its
northward
course.
This
wind,
Hadley
argued,
produced
the
steady
breeze
north
of
the
Horse
Latitudes
that
blew
the
explorers
back
home.
A
century
later,
a
French
mathematician,
Gaspard
Coriolis,
worked
out
the
mathematics
of
all
this,
to
prove
that
any
object
moving
over
the
northern
hemisphere
would
seem
to
veer
to
the
right,
while
any
object
moving
over
the
southern
hemisphere
would
appear
to
veer
left.
Isaac,
in
his
1891
talk
to
the
Galveston
YMCA,
gave
a
cruelly
detailed
explanation
of
the
Coriolis
effect.
The
crowd
listened
with
iron
concentration.
".
.
.
At
latitude
30
degrees
the
velocity
of
the
earth
eastward
is
897
miles
per
hour,
and
at
45
degrees
it
is
732
miles
per
hour,
or
165
miles
less.
Now,
if
a
mass
of
air
in
a
quiescent
state
were
transferred
instantly
from
the
thirtieth
parallel
to
the
forty-fifth
parallel
it
would
be
found
to
have
a
relative
motion
eastward
of
165
miles
per
hour
greater
than
that
of
the
parallel
arrived
at,
and
if
it
had
been
transferred
from
45
degrees
to
30
degrees,
with
the
motion
which
it
had
at
45,
it
would
be
165
miles
slower
than
the
earth
at
the
thirtieth
parallel,
and
this
would
give
a
relative
velocity
westward
of
165
miles
per
hour."
A
twentieth-century
audience
would
have
shot
Isaac
dead.
HADLEY'S
THEORY
DID
little
to
advance
man's
immediate
understanding
of
storms
in
general
and
hurricanes
in
particular.
Meanwhile,
the
danger
grew.
Ship
traffic
increased.
Nations
deployed
battle
squadrons
to
protect
their
interests.
No
single
period
highlighted
the
threat
to
national
defense
more
than
the
wild
hurricane
season
of
1780,
during
which
three
intense
hurricanes
scoured
the
Caribbean
in
a
period
of
two
weeks
and
impartially
ravaged
the
forces
of
France,
Spain,
and
Britain,
even
as
these
nations
harried
one
another
in
the
war-convulsed
seas
of
the
Americas.
The
first
hurricane
arrived
October
3
and
leveled
the
Jamaican
town
of
Savanna-la-Mar,
and
in
the
process
overtook
scores
of
British
warships.
Hundreds
of
seamen
simply
vanished.
"Who
can
attempt
to
describe
the
appearance
of
things
upon
deck?"
wrote
Lt.
Benjamin
Archer,
who
survived
the
foundering
of
the
forty-four-gun
Phoenix.
"If
I
was
to
write
forever,
I
could
not
give
you
an
idea
of
it
—
a
total
darkness
all
above;
the
sea
on
fire,
running
as
it
were
in
Alps,
or
Peaks
of
Tener-iffe;
(mountains
are
too
common
an
idea;)
the
wind
roaring
louder
than
thunder
(absolutely
no
flight
of
imagination,)
the
whole
made
more
terrible,
if
possible,
by
a
very
uncommon
kind
of
blue
lightning."
The
second
hurricane,
called
simply
the
Great
Hurricane,
struck
Barbados
on
October
10
and
11,
killing
4,326
people
on
that
island
alone.
The
toll
throughout
the
Indies
reached
22,000.
Britain's
Sir
George
Rodney,
deeply
shaken
by
the
disaster,
described
what
remained
of
Barbados:
"The
most
beautiful
island
in
the
world
has
the
appearance
of
a
country
laid
waste
by
fire,
and
sword,
and
appears
to
the
imagination
more
dreadful
than
it
is
possible
for
me
to
find
words
to
express."
The
storm
lurched
into
French
territory
next
and
sank
at
least
forty
ships
in
a
French
convoy
off
Martinique,
with
a
loss
of
five
thousand
soldiers.
The
third
hurricane
struck
just
as
Spain's
Admiral
Don
Jose
Solano
was
leading
a
force
of
six
dozen
ships
and
four
thousand
soldiers
for
a
surprise
attack
against
the
British
at
Pensacola.
The
storm
so
damaged
and
dispersed
the
fleet,
the
admiral
called
off
the
attack.
In
keeping
with
the
early
custom
of
naming
storms
after
prominent
victims,
the
hurricane
became
known
as
Solano's
Storm.
Together
the
three
hurricanes
did
so
much
damage
to
Britain's
Caribbean
forces
that
the
Admiralty
canceled
a
secret
plan
to
seize
Puerto
Rico
from
the
Spanish.
No
navy
could
have
made
such
short
work
of
the
military
might
of
the
world's
greatest
powers.
Clearly
hurricanes
posed
a
greater
menace
than
any
single
nation's
forces.
But
what
could
one
do?
Captains
could
not
even
measure
the
velocity
of
the
winds
they
encountered,
for
no
effective
means
existed
of
measuring
wind
from
a
rolling,
heaving
ship.
Sir
Francis
Beaufort
tried
to
solve
that
problem
by
devising
a
wind
scale
that
allowed
mariners
to
gauge
the
intensity
of
wind
by
the
look
of
seas
and
sails.
Force
0
meant
winds
so
light
a
ship
could
not
move.
Force
12
was
a
hurricane,
when
no
sail
could
be
exposed.
Beaufort's
intent
was
to
bring
uniformity,
and
with
it
comparability,
to
weather
observations
made
at
sea.
His
scale
included
no
actual
wind
velocities
—
these
were
added
much
later.
The
first
captain
to
use
the
scale
in
an
official
log
did
so
on
December
22,1831,
the
first
day
of
a
voyage
of
exploration.
The
captain
was
Robert
Fitzroy;
his
ship's
company
included
a
naturalist
named
Darwin.
Hurricanes,
once
such
a
surprise
to
Columbus,
became
lodged
firmly
in
the
public
psyche
as
just
another
hazard
of
venturing
upon
the
sea
—
acts
of
God,
still,
and
against
which
one
could
do
nothing.
With
tragic
regularity,
captains
sailed
their
ships
right
into
the
worst
storms
that
ever
danced
upon
the
earth.
Seamen
resigned
themselves
to
the
inevitability
of
hurricanes
and
prayed
they
would
never
have
to
experience
their
full
fury.
But
others
were
not
so
willing
to
surrender.
They
began
an
earnest
search
for
the
elusive
"Law
of
Storms,"
the
physical
code
that
scientists
hoped
would
help
mariners
predict
and
avoid
—
perhaps
even
profit
from
—
the
hurricanes
and
typhoons
that
so
threatened
the
welfare
of
nations.