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  • 6/11/2025
The 10-year attempt to keep the Leaning Tower of Pisa, which began falling 800 years ago, from finally collapsing.

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00:01During the following program, look for NOVA's webmarkers which lead you to more information at our website.
00:07In the 12th century, in a Europe ravaged by war, famine and disease, the rich Italian city of Pisa rose above the horror by erecting the most magnificent tower the world had ever seen.
00:37800 years later, this bold architectural dream has produced a nightmare.
00:51Inch by inch, year by year, the tower is slowly tipping over.
00:57What was once an amusing tourist attraction is now a threat.
01:02The top hangs 17 feet south of the base and the leaning tower of Pisa is on the brink of disaster.
01:10A collapse might be triggered by a storm or an earthquake.
01:16I'm astonished at still standing.
01:22Pisa is shaken by several tremors each year.
01:26If an earthquake rocks the ground or a storm sweeps in from the nearby coast, one of the wonders of the world will be lost forever.
01:44Can modern ingenuity prevent this nightmare and save Pisa?
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02:08Major funding for NOVA is provided by The Park Foundation, dedicated to educational and educational,
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02:14Pisa.
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02:16for NOVA is provided by the Park Foundation, dedicated to education and quality television.
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02:35CNET.com, the source for computers and technology.
02:41This program is funded in part by Northwestern Mutual Life.
02:46Which has been protecting families and businesses for generations.
02:50Have you heard from the Quiet Company?
02:52Northwestern Mutual Life.
02:55And by the Corporation for Public Broadcasting and viewers like you.
02:59Over the last decade, teams of engineers and scientists have been at work in the Italian city of Pisa.
03:21A $20 million struggle to save the Leaning Tower is approaching a crucial stage.
03:30Built 800 years ago to house the bells of the vast cathedral of the Piazza dei Miracoli, or Place of Miracles,
03:37the Leaning Tower of Pisa is one of the wonders of the world.
03:41And one of Europe's top tourist attractions, with over 6 million visitors each year.
03:56But the risk of collapse is now so high, tourists are banned from entering the tower.
04:02People still travel thousands of miles to steal a glimpse.
04:14A hundred and eighty feet high, with columns, carvings and brickwork all of matching marble.
04:19Even if it were straight, this would be a breathtaking building.
04:27There are almost 200 columns supporting the six stories of external arcades.
04:32These walkways in the air must have been a thrilling experience for the medieval Pisans.
04:49Even today, the view is spectacular.
04:58The infamous lean is not intentional.
05:01The gravity-defying five-and-a-half-degree tilt is a tragic flaw that could eventually destroy the tower.
05:21Towers do collapse.
05:23In 1989, in Pavia, a few hundred miles north of Pisa,
05:27a 14th-century bell tower collapsed, killing four bystanders.
05:34Pavia's tower wasn't even leaning.
05:43The Italian government reacted.
05:45And here, in the shadow of Pisa's tower, a committee of experts has been assembled.
05:50Nobody has refused this invitation.
05:57Saving Pisa is the greatest prize in civil engineering.
06:02Among the brilliant minds rising to this challenge are Giorgio Macchi of Pavia
06:10and John Berlund, and John Berlund, of Imperial College London.
06:17When you come in through the West Gate and see this glistening white structure looming over the cathedral
06:24with its lovely symmetry, it is beautiful.
06:28But it's breathtaking.
06:29The fact that it hasn't fallen over, that it's just shimmering on the edge.
06:38Berlund, a soil engineer, digs into problems below ground,
06:43while Giorgio Macchi, a structural engineer, attacks weaknesses in the tower itself.
06:50My work is on a structural problem, so I saw immediately the structural risk.
06:58In my opinion, the tower is in real danger.
07:07Before the committee intervenes, they must first investigate.
07:12So many analytical devices are fixed to the tower,
07:15it becomes the most monitored building in the world.
07:20A circular sensor, which can register a vibration from a footstep,
07:25runs around the inner walls.
07:29Metal clamps detect any shift in 25 of the tower's largest cracks.
07:35Three plumb lines hang from the top level.
07:42Taut cross wires measure deformations in the walls.
07:50Some startling secrets are exposed.
07:55The tower reacts to changes in the elements.
07:58Every day, the entire building sways in a minute circle,
08:09not more than a hundredth of an inch across.
08:12This infrared camera shows why.
08:15The lens is sensitive to heat, which is displayed as white.
08:19The sun heats the south side more than the north.
08:26The marble there expands, creating an imbalance and increasing the lean.
08:31At night, it will shrink back.
08:37Larger movements are recorded during rainstorms.
08:40We get these extraordinarily heavy storms in Pisa and the water table rises very quickly indeed.
08:49And it rises on one side more than on the other.
08:52And it lifts that side, it happens to be the north side.
08:56It lifts the north side a bit so the tower goes to the south when the water table comes up.
09:01When the rain stops, the tower will move back.
09:07Committee member Carlo Vigiani has studied the tower for 35 years.
09:13In this moment, the tower feels very sad and increases its leaning.
09:19But when the sun will come back, I say she, probably I say it, will come back again.
09:26The sensitivity to the water table suggests there is a problem in the ground below the tower.
09:37This will be an important part of the investigation.
09:40But first, the committee faces a more immediate danger.
09:45Structural engineer Giorgio Maki must deal with a series of massive flaws in the tower's structure.
09:56The tower is a hollow cylinder, 45 feet across.
10:02In most places, the walls are 9 feet thick.
10:07But corkscrewing through the walls is a staircase wide enough for two peasants to climb side by side.
10:14This reduces the thickness of the walls to barely a yard in some places.
10:18This would be just adequate if these walls were solid marble, as they appear to be.
10:26But probes reveal otherwise.
10:30This marble facing is only 25 centimeters thick.
10:36And behind it, there is a conglomerate of stones and lime,
10:42which is a very, very low resistance.
10:45Medieval masons, often filled in walls with stones and lime,
10:53but it severely weakens the structure.
10:57What's more, there are several holes in the conglomerate,
10:59created by the original builder's wooden scaffold.
11:04The holes are some 40 centimeters high holes,
11:09so they reduce the resistance area of the wall in a considerable way.
11:16Turns out that this elegant marble facing is the tower's main support.
11:23The stress created by the lean falls mainly on this thin facade.
11:29That's why many of the bricks are cracked.
11:35One may be the start of a collapse.
11:38To pinpoint this potential catastrophe,
11:45Maki must locate the tower's zone of maximum stress.
11:52Detailed measurements and data from the monitors
11:55are fed into a computer,
11:57which calculates structural stress and highlights it in blue.
12:01The largest stresses are on the south side,
12:07below the lean, on the second story,
12:10where a doorway meets the staircase.
12:12This is where the collapse will begin.
12:15By calculation, we found that this is the really critical point.
12:24If the marble here gives way,
12:27the 14,000-ton tower won't merely crumble.
12:31The tensions accumulated over centuries
12:34will be unleashed with immense and sudden force.
12:37Thankfully, this ticking time bomb
12:53has always been well-maintained.
12:55Even today, minor repairs are carried out by Pisan stonemasons
13:04who replace some of the damaged marble
13:06with newly chiseled blocks.
13:13There were very many substitutions of stones in this area.
13:18You can see here is the original stone.
13:22These are completely substituted stones here and there
13:28and completely substituted in this area.
13:35But traditional maintenance will no longer contain
13:38the growing stress of the lean.
13:41In 1992, a dozen plastic-coated metal tendons
13:45are wrapped tight around the critical second story.
13:48The cracks are held shut and the collapse prevented,
13:53or at least delayed.
14:03This is one of the great monuments of medieval Europe,
14:07so the unsightly tendons cannot remain in place here indefinitely.
14:11Now that the structure has been strengthened,
14:16the committee begins to search for a permanent solution.
14:20The quest carries the engineers into strange territory,
14:24deep into the ancient mysteries of the tower.
14:29Medieval Italy was tower-mad.
14:33Skylines like this one at San Gimignano,
14:35just south of Pisa, were commonplace.
14:37For the princes and merchants,
14:41the bigger your tower,
14:42the more wealth and power you projected.
14:47Today, Pisa is a quiet university town.
14:51But medieval Pisa was an aggressive trading power
14:55and one of the richest cities in the world.
14:59Piero Pierotti is a historian at Pisa University.
15:09Although not on the committee,
15:10he is an expert on the tower.
15:15It's said that the most important families in Pisa
15:17ate off gold plates.
15:19There's no doubt that some had grown very rich
15:21from seagoing trade.
15:23And this wealth must have inspired the attempt
15:25to do something outstanding for the city.
15:29In 1064, just inside the north wall of the city,
15:35work began on a massive cathedral.
15:39The wedding cake tiers of marble columns
15:41were an early expression of the style
15:44that would later embellish the tower.
15:49Inside are more colonnades.
15:51Horizontal layers of black and white marble
16:00seem to draw worshippers
16:02towards the artistic climax,
16:04the apse,
16:05with its haunting mosaic,
16:07Christ in Majesty.
16:10The Pisa borrowed ideas from other cultures.
16:13There are Byzantine mosaics
16:15and an Islamic dome.
16:21And they recycled the marble
16:23of classical buildings,
16:25inviting comparisons
16:26to the glory of ancient Rome.
16:33They built what is still
16:35one of the largest baptistries in Italy.
16:37Here, the richest citizens
16:42were christened in style.
16:45This bizarre architectural mix
16:48has gothic pinnacles
16:49sprouting from the trademark
16:51Romanesque colonnades.
17:00Still, the medieval peasants
17:02weren't satisfied.
17:03They decided to give their new cathedral
17:07the most extravagant bell tower
17:09the world had ever seen.
17:16But their ambition
17:18exceeded good building practice.
17:20While all the other monuments
17:27of the piazza
17:27have been signed
17:28by their architects,
17:30the architect of the tower
17:32is a mystery.
17:34Nobody put their name
17:35on the tower.
17:37The builders must have felt
17:38that the plan for the tower
17:39was overambitious
17:41because they knew
17:43that the ground in Pisa
17:44tended to give way easily.
17:50This painting reveals
17:53that Pisan masons
17:54had plenty of experience
17:55building towers.
17:58What were the soil conditions
18:00that worried them
18:01800 years ago?
18:04Between Pisa and the nearby coast
18:07is an alluvial marsh.
18:09Perhaps this is what the ground
18:11around the tower was like
18:12before construction began.
18:14Soil engineer John Berlin
18:18travels to the shoreline
18:20to assess what effect
18:21this ground might have had
18:22upon the tower.
18:26Well, about 10,000 years ago
18:28the location of the tower
18:30was actually a river estuary
18:32and the tide would come in and out
18:35and the floods would come down
18:37each year
18:37and they'd deposit
18:39sand and silt
18:42and the soil beneath the tower
18:44was actually
18:45very much like
18:46this beach
18:47that's soft.
18:50You sink into it
18:51and that's what they actually
18:52built the tower on.
19:01A team of scientists
19:03performs an ingenious experiment
19:05to reconstruct Pisa's
19:07geological history.
19:14A three-foot-high
19:16aluminum model
19:17of the tower
19:18is placed upright
19:19on sand
19:20which has been carefully arranged
19:21to mimic the silt
19:23below the tower.
19:35Sandy silt
19:39and metal tower
19:40are then lowered
19:41into a centrifuge
19:42which will simulate
19:44the effect
19:44of hundreds of years
19:45of gravity.
19:55Centuries are compressed
19:57into a few weeks.
20:05When taken out
20:12of the centrifuge
20:13this tower
20:14leans just like
20:15the real thing.
20:18Not only did the model sink
20:19but it sank unevenly
20:21just like the real tower
20:23which was built on ground
20:25no more solid
20:26or consistent
20:26than a beach.
20:27And the reason
20:35why it's leaning
20:36is because
20:37the soil
20:38on the south side
20:39is just a little bit
20:40more compressible
20:41than on the north side.
20:43So the tower
20:47settled more deeply
20:48into the softer silt
20:49on the south side.
20:52The scientists
20:53have explained
20:54the leaning tower
20:55of Pisa.
20:56Now they must
20:57save the tower
20:58by finding a way
20:59to halt
21:00even reverse
21:02the lean.
21:07Proposals arrive
21:08in Pisa
21:09from all over the world.
21:11Some devised
21:12by qualified engineers
21:14others by school children.
21:22But most rely
21:23on some version
21:25of a huge prop.
21:27Aesthetically
21:27this would be
21:29unacceptable
21:29and would probably
21:31destroy the tower.
21:33A lot of people say
21:34why can't we just prop it
21:35or why can't we
21:36just push it back
21:37and this experiment
21:38shows why that's
21:39about the most dangerous
21:40thing you could do
21:41in fact.
21:42Mason is represented
21:43by this acrylic cylinder
21:45and this weight here
21:47applies weight
21:49to the top
21:50of the tower.
21:51We'll increase
21:52the inclination
21:52of the tower
21:53and prop it
21:55or push it.
21:57And you can see
21:58what happens.
21:59It just literally
22:00collapses.
22:01The search for a solution
22:08takes the engineers
22:10back into history.
22:14The tower
22:15has always been cared
22:17for by an organization
22:18called the opera
22:19whose presidents
22:21represent an unbroken
22:22line of craftsmen
22:23right back
22:24to the 11th century.
22:25The opera archives
22:39contain a priceless
22:40horde of information.
22:43A report from 1550
22:46showed the top
22:47was already
22:4712 feet south
22:48of the base.
22:49The first scientific measurement
22:58was made by two
23:00British architects
23:01Edward Cressy
23:02and George Taylor.
23:02But this was
23:08a static observation.
23:15Regular surveys
23:16have been made
23:17since 1911.
23:18and these reveal
23:22the tower
23:23has stopped
23:24settling into the silt.
23:28The ground
23:29has hardened.
23:30The tower
23:31is no longer sinking.
23:33It's capsizing.
23:35And as soon
23:36as we discovered
23:37that
23:37we thought
23:39ah
23:39if this side
23:40is coming up
23:41then it's rather
23:42like sitting
23:43on a sailing boat.
23:44If you can just
23:45lean out
23:46you can pull it
23:48back a little bit.
23:50Surely
23:51it would be safe
23:51to put
23:52temporarily
23:53some load here
23:54to reduce
23:55the tendency
23:56for the tower
23:57to fall over.
24:00In July
24:011993
24:02the engineers
24:04begin to act.
24:08They load
24:09600 tons
24:10of lead ingots
24:11on the rising
24:12north side.
24:18as the lead
24:20is piled up
24:21there's always
24:22the danger
24:23that the ground
24:23might give way
24:24again.
24:26So the tower's
24:27reaction is
24:28scrutinized
24:29by the electronic
24:30monitors.
24:34They can tell us
24:35to one hundredth
24:36of a millimeter
24:37how much the tower
24:39is moving at the top.
24:40So we did this
24:41very gradually
24:42over a four or five
24:43month period
24:44putting the lead
24:45weight on
24:45leaving it
24:46for a day
24:47making measurements
24:48putting another
24:49one on
24:50and so on.
24:55The lean
24:56is brought
24:56under control
24:57for the first
24:58time in 800
24:59years
24:59but the beautiful
25:01tower
25:01has become
25:02an eyesore.
25:06So a permanent
25:07solution
25:08is devised
25:08with no lead
25:09weights.
25:12It is based
25:13on removing
25:13soil from
25:14beneath the
25:15tower.
25:16This model
25:17demonstrates
25:18the soil
25:18extraction
25:19technique.
25:20We drill in
25:21under the
25:22tower
25:22with a
25:23specially
25:23designed
25:24drill
25:24which
25:24causes
25:25no
25:25disturbance
25:26to the
25:26ground
25:27and when
25:28it's
25:28at the
25:29location
25:29we want
25:30it
25:30we can
25:30then
25:31gently
25:32pull
25:32the
25:32drill
25:32out
25:33so if
25:33we look
25:33at this
25:34the
25:34soil
25:35will
25:35then
25:36close
25:36in
25:36the
25:36cavity
25:37and
25:38we'll
25:38see
25:38the
25:38tower
25:39rotating
25:39back
25:40towards
25:41the
25:42north
25:42side
25:43as
25:44we
25:44under
25:44excavate
25:45a
25:4710%
25:47reduction
25:48in
25:48inclination
25:49will
25:49reduce
25:50the
25:50stresses
25:51by
25:5110%
25:52in
25:52the
25:52masonry
25:53and
25:54that's
25:54a
25:54very
25:55reasonable
25:55amount
25:56Reducing
25:58the
25:58lean
25:58by
25:5810%
25:59will
26:00shift
26:00the
26:00tower
26:00north
26:01by
26:01half
26:02a
26:02degree
26:02In
26:06the
26:06piazza
26:06an
26:07experiment
26:07is done
26:08on a
26:09concrete
26:09test
26:09tower
26:10which is
26:10taller
26:11and heavier
26:11on the
26:12south
26:12side
26:12and so
26:13simulates
26:14the forces
26:15under the
26:15lopsided
26:16leaning
26:16tower
26:17and we
26:20were extracting
26:21soil
26:22over a
26:23length
26:23of this
26:23sort
26:24and you
26:25can see
26:25here how
26:26the ground
26:26has
26:27subsided
26:28and that
26:29brought
26:29the whole
26:30trial footing
26:31northwards
26:33by about
26:34half a
26:34degree
26:34but
26:36some
26:36have
26:37doubts
26:37about
26:38soil
26:38extraction
26:39such
26:40intervention
26:40has been
26:41tested
26:41on
26:42specimen
26:42and
26:44this
26:44works
26:44very
26:45well
26:45but
26:46to
26:47extend
26:48this
26:48intervention
26:49under
26:50the
26:50tower
26:50in
26:51this
26:51special
26:52situation
26:52which
26:52has
26:53been
26:53formed
26:54in
26:54700
26:55years
26:55there
26:56is
26:56still
26:57a
26:57residual
26:57risk
26:58and
26:58the
26:59committee
26:59is
26:59thinking
27:00about
27:00that
27:01at
27:06tense
27:06committee
27:07meetings
27:07carlo
27:08vigiani
27:09becomes
27:10the
27:10first
27:10apostle
27:10of
27:11soil
27:11extraction
27:12if
27:14we
27:14go
27:14back
27:14by
27:15half
27:15a
27:15degree
27:15then
27:16even
27:16if
27:16the
27:17worst
27:17happens
27:17which
27:18is
27:18that
27:18the
27:18tower
27:19starts
27:19to
27:19move
27:19again
27:20as
27:20soon
27:20as
27:20we
27:20leave
27:21it
27:21it
27:21will
27:21take
27:22300
27:22years
27:23to
27:23get
27:23back
27:24to
27:24the
27:24position
27:24it's
27:25in
27:25now
27:25but
27:27some
27:29have
27:29no
27:30faith
27:30in
27:30this
27:30time
27:31machine
27:31i'm
27:34a bit
27:34puzzled
27:35by what
27:35carlo
27:35is
27:36saying
27:36are
27:37you
27:37suggesting
27:37we
27:38can
27:38go
27:38back
27:38in
27:39time
27:39300
27:40years
27:41there
27:44is
27:44so
27:44much
27:44at
27:44stake
27:45it's
27:45hard
27:46to
27:46reach
27:46an
27:46agreement
27:46especially
27:48with
27:48so
27:49many
27:49experts
27:50what
27:51is
27:51very
27:52peculiar
27:52of
27:52this
27:53committee
27:53is
27:53that
27:54it
27:54is
27:55a
27:55multidisciplinary
27:56committee
27:57there
27:57are
27:57people
27:58from
27:59this
27:59side
27:59of
27:59history
28:00of
28:00art
28:00of
28:00restoration
28:01and
28:01engineers
28:03geotechnical
28:04engineers
28:05structural
28:05engineers
28:06and
28:06it
28:07is
28:07not
28:08easy
28:08to
28:08work
28:08together
28:09for
28:09such
28:10differently
28:10minded
28:11people
28:11before
28:15approving
28:15soil
28:16extraction
28:16the
28:17fractious
28:17committee
28:18demands
28:18conclusive
28:19evidence
28:20that this
28:20intervention
28:21will not
28:22damage
28:22the
28:23tower
28:23the
28:24soil
28:25engineers
28:25must
28:26establish
28:26precisely
28:27how this
28:28fragile
28:28structure
28:29reacts
28:29to
28:30changes
28:30in the
28:31ground
28:31below
28:31it
28:32yet
28:35again
28:36the
28:37answer
28:37lies
28:38in the
28:38past
28:38jane morley
28:42jane morley
28:42is an
28:43architectural
28:44historian
28:44who has
28:45studied
28:45the tower
28:46extensively
28:46i don't think
28:48anyone
28:49short of god
28:50will understand
28:51what
28:52it
28:53took
28:53to
28:54build
28:54this
28:54tower
28:54and
28:55why
28:56it's
28:57doing
28:57what
28:57it's
28:57doing
28:57now
28:58the
28:59people
28:59that
28:59built
29:00this
29:00were
29:00not
29:00scientists
29:01or
29:01engineers
29:02they
29:03probably
29:03had
29:03very
29:03little
29:04formal
29:04education
29:05they
29:05were
29:05builders
29:05and
29:06they
29:06had
29:07a
29:07lot
29:07of
29:07knowledge
29:08knowledge
29:08that
29:08isn't
29:09quantified
29:10or codified
29:11it's
29:12what
29:12you
29:12learn
29:13by
29:13doing
29:13it's
29:13what
29:13you
29:14learn
29:14by
29:14being
29:15a
29:15builder
29:15perhaps
29:21something
29:22the
29:22medieval
29:22builders
29:23did
29:23will
29:24give
29:24modern
29:24engineers
29:25useful
29:25insights
29:26into
29:26the
29:26mysterious
29:27interaction
29:28between
29:29this
29:29structure
29:29and
29:30the
29:30soil
29:31the
29:34first
29:34clue
29:34is
29:34in
29:35the
29:35impressive
29:35craftsmanship
29:36of
29:37the
29:37exterior
29:37marble
29:38which
29:40stone
29:41layer
29:42is
29:42precise
29:44within
29:45less
29:46than
29:46a
29:46millimeter
29:46and
29:47this
29:47is
29:47the
29:48reason
29:48why
29:48we
29:48can
29:49get
29:50so
29:50many
29:50information
29:51by
29:51just
29:51by
29:52measuring
29:52these
29:52stones
29:53you
29:54can
29:54see
29:54that
29:55in
29:55most
29:55of
29:55the
29:56stone
29:56there
29:56is
29:56no
29:57most
29:57at
29:57all
29:57at
29:58the
29:58contact
29:58between
29:59the
29:59two
30:00stones
30:00it
30:01depends
30:01on
30:01the
30:02high
30:02quality
30:02of
30:02workmanship
30:03these
30:06stones
30:07reveal
30:08an
30:08extraordinary
30:09history
30:09construction
30:15of the
30:15tower
30:15began
30:16in
30:161172
30:17after
30:20about
30:21six
30:21years
30:21the
30:21masons
30:22had
30:22reached
30:22the
30:22fourth
30:23level
30:23but
30:24then
30:24they
30:24stopped
30:25the
30:30tower
30:31was
30:31abandoned
30:31for
30:32almost
30:32a
30:32century
30:33probably
30:34this
30:35was
30:35due
30:35to
30:35political
30:36and
30:36economic
30:36strife
30:37but
30:39perhaps
30:39the
30:40delay
30:40was
30:41really
30:41a
30:41brilliant
30:42strategy
30:42if
30:44they
30:44built
30:44the
30:45tower
30:45in
30:45one
30:46go
30:46it
30:47literally
30:47would
30:48have
30:48fallen
30:48over
30:49as
30:49this
30:49one
30:49is
30:50you
30:50can
30:50just
30:50see
30:50it
30:51settling
30:51down
30:51it
30:53just
30:54collapsed
30:54and
30:55that's
30:55what
30:55would
30:55have
30:56happened
30:56if
30:56they
30:56built
30:56it
30:57all
30:57in
30:57one
30:57shot
30:58so
31:00what
31:00they
31:00actually
31:00did
31:01was
31:01they
31:01built
31:02the
31:02tower
31:02up
31:03to
31:03a
31:03little
31:03above
31:04the
31:04third
31:04story
31:05and
31:05then
31:05they
31:06stopped
31:06and
31:07the
31:07weight
31:07of
31:07that
31:08tower
31:08in
31:08that
31:08state
31:09squeezed
31:10the
31:10underlying
31:11ground
31:11and
31:12over
31:13the
31:13years
31:13the
31:13ground
31:13became
31:14stronger
31:14so
31:14when
31:15they
31:15came
31:15back
31:15a
31:16hundred
31:16years
31:17later
31:17it
31:18could
31:18take
31:18the
31:18full
31:19weight
31:19of
31:19the
31:19tower
31:19when
31:22construction
31:23did
31:23resume
31:23the
31:24masons
31:25must
31:25have
31:25noticed
31:26a
31:26slight
31:26lean
31:27to
31:27the
31:27north
31:27so
31:29they
31:29tried
31:30to
31:30straighten
31:30the
31:31tower
31:31what
31:32they
31:32did
31:33is
31:33to
31:33have
31:33slightly
31:35higher
31:36stones
31:36on
31:37the
31:37side
31:38where
31:38the
31:38tower
31:39was
31:39leaning
31:39the
31:42corrections
31:42are
31:42so
31:43small
31:43they
31:43cannot
31:44be
31:44seen
31:44with
31:44the
31:45naked
31:45eye
31:45and
31:45were
31:46only
31:46discovered
31:46recently
31:47by
31:47detailed
31:48surveys
31:48but
31:52as
31:53the
31:53masons
31:53straightened
31:54the
31:54tower
31:54it
31:55lurched
31:56in
31:56the
31:56opposite
31:56direction
31:57when
32:00it
32:00reached
32:00the
32:00seventh
32:01story
32:01work
32:02stopped
32:02again
32:03over
32:07the
32:07next
32:08ninety
32:08years
32:09the
32:09southward
32:09lean
32:10grew
32:10to
32:10over
32:10one
32:11and
32:11a
32:11half
32:11degrees
32:12a
32:14severe
32:14inclination
32:15that
32:16did
32:16not
32:16deter
32:17the
32:17masons
32:17from
32:17adding
32:18a
32:18heavy
32:18bell
32:18chamber
32:19when
32:23they
32:23started
32:23again
32:24to
32:24construct
32:25the
32:25bell
32:25tower
32:26they
32:26had
32:27to
32:27make
32:28a
32:28substantial
32:29correction
32:30and
32:30they
32:30did
32:31it
32:31by
32:31changing
32:32the
32:32number
32:32of
32:32steps
32:33according
32:34to
32:34the
32:34direction
32:35in
32:35this
32:36side
32:36we
32:36are
32:36on
32:37the
32:37north
32:37side
32:38we
32:38have
32:39only
32:39four
32:39steps
32:40we
32:40will
32:40see
32:41that
32:41on
32:41the
32:41opposite
32:41side
32:42we
32:42have
32:42six
32:43steps
32:43now
32:46we
32:46are
32:46on
32:46the
32:47south
32:47side
32:47where
32:48the
32:48steps
32:48are
32:49six
32:49just
32:50to
32:51correct
32:51for
32:52the
32:52inclination
32:52and
32:53I
32:53I
32:53feel
32:54this
32:54tower
32:54personally
32:55is a
32:55challenge
32:56I
32:57cannot
32:57conceive
32:59the
32:59man
32:59constructing
33:00it
33:01knowing
33:01that
33:02it
33:02was
33:02previously
33:03leaning
33:04and
33:05going
33:05on
33:05and
33:06finishing
33:06it
33:07as a
33:12result
33:12of
33:12the
33:12delays
33:13and
33:13corrections
33:13over
33:14generations
33:14the
33:15tower
33:15appears
33:16banana
33:17shaped
33:17this
33:22deformity
33:22provides
33:23the
33:24vital
33:24clue
33:24to
33:24the
33:25relationship
33:25between
33:25the
33:26soil
33:26and
33:26the
33:26structure
33:27and
33:28is
33:28the
33:28basis
33:29of
33:29Berlin's
33:30computer
33:30model
33:30we've
33:32been
33:33through
33:33a
33:34period
33:34of
33:34about
33:34three
33:35years
33:35of
33:36a
33:37very
33:37very
33:38intense
33:38study
33:38using
33:39our
33:39computer
33:39models
33:40studying
33:41soil
33:41extraction
33:42all
33:43the
33:43results
33:43have
33:43been
33:44positive
33:44we've
33:44learnt
33:45what
33:45we
33:46can
33:46do
33:46and
33:46what
33:46we
33:46can't
33:47do
33:47but
33:49some
33:49believe
33:50a
33:50computer
33:50model
33:51oversimplifies
33:52the
33:52construction
33:53of
33:53the
33:53tower
33:54you
33:58had
33:58different
33:59people
33:59working
33:59on it
33:59at
34:00different
34:00times
34:00with
34:01different
34:01states
34:02of
34:02knowledge
34:02about
34:03what
34:03structures
34:04like
34:04this
34:04can
34:04do
34:05what
34:05they
34:05can't
34:05do
34:05what
34:06happens
34:06to
34:06them
34:06over
34:06time
34:07and
34:07you've
34:07got
34:08different
34:08sections
34:08of
34:09the
34:09tower
34:09that
34:09are
34:09different
34:09geometries
34:10so
34:11to
34:12write
34:12it
34:12any
34:12degree
34:13you may
34:14not
34:14get
34:14the
34:14predicted
34:15structural
34:15action
34:16that
34:16you
34:16would
34:16want
34:16the
34:20proof
34:21the
34:21committee
34:21demands
34:22remains
34:23elusive
34:24in the
34:26meantime
34:26its
34:26deliberations
34:27are
34:27complicated
34:28by yet
34:29another
34:29proposal
34:30a plan
34:34to replace
34:34the
34:35unsightly
34:36tendons
34:36in his
34:42lab
34:43structural
34:43engineer
34:44Giorgio
34:44Macchi
34:45experiments
34:46on a
34:46three-quarter
34:47inch
34:47thick
34:48steel
34:48bolt
34:49that fits
34:49inside
34:50the marble
34:51blocks
34:51stiffening
34:52them
34:53from within
34:53but there
34:56is a
34:57risk
34:57the
34:57bolt
34:57might
34:58actually
34:58weaken
34:58the
34:59marble
34:59on a
35:02test
35:02rig
35:02a
35:03marble
35:03block
35:03is
35:04forced
35:04upwards
35:04while
35:05the
35:05bolt
35:06is
35:06held
35:06in
35:06a
35:06vise
35:07eventually
35:09one
35:10will
35:10break
35:11but
35:11Macchi
35:12has
35:12calculated
35:13it
35:13will
35:13not
35:14be
35:14the
35:14marble
35:14the
35:24force
35:24builds
35:25up to
35:2512
35:26tons
35:26then
35:29the
35:31bolt
35:31snaps
35:32leaving
35:33the
35:33marble
35:33unharmed
35:34suggesting
35:35a way
35:35to
35:36strengthen
35:36the
35:36tower
35:36without
35:37defacing
35:38it
35:38we
35:39should
35:40do
35:40something
35:41very
35:41quickly
35:42we
35:44know
35:44which
35:44are
35:45the
35:45problems
35:45of
35:46the
35:46tower
35:46and
35:48I
35:48think
35:48that
35:48further
35:49research
35:50could
35:50not
35:50improve
35:51very
35:51much
35:52our
35:52knowledge
35:53now
35:54so
35:59there
35:59are
35:59two
35:59long
36:00term
36:00solutions
36:01for
36:01the
36:01tower
36:01one
36:03would
36:03stabilize
36:03the
36:04structure
36:04with
36:05internal
36:05bolts
36:05the
36:06other
36:06would
36:06reverse
36:07the
36:07lean
36:07through
36:08soil
36:08extraction
36:09faced
36:11with
36:11this
36:11choice
36:12the
36:12committee
36:13hesitates
36:15their
36:16indecision
36:16fueled
36:17by a
36:17frightening
36:18history
36:18there
36:19have
36:20been
36:20many
36:20previous
36:21interventions
36:21all
36:22have
36:23failed
36:23the
36:31disastrous
36:31medley
36:32began
36:33with
36:33the
36:33digging
36:33of
36:33this
36:34trench
36:34around
36:34the
36:34base
36:35of
36:35the
36:35tower
36:35this
36:37is
36:37called
36:37the
36:37catino
36:38it's
36:39a
36:39walkway
36:39and
36:40it
36:41was
36:41excavated
36:42by
36:42an
36:42architect
36:42called
36:43Gerardesca
36:43in
36:441838
36:46now
36:47it's
36:47important
36:48to
36:48remember
36:48that
36:48the
36:49tower
36:50has
36:50settled
36:50about
36:51three
36:51meters
36:52since
36:53it
36:53was
36:53built
36:53as a
36:57result
36:58the
36:59elegant
36:59carvings
37:00at the
37:00base
37:00of the
37:00columns
37:01on the
37:01ground
37:01floor
37:02had
37:02sunk
37:03below
37:03ground
37:04and
37:07Gerardesca
37:08argued
37:09that it
37:09would be
37:09lovely
37:10to reveal
37:11them
37:11so that
37:12people
37:12walking
37:13around
37:13the
37:13piazza
37:14could
37:14view
37:15the
37:15base
37:15of
37:15the
37:16columns
37:16as
37:17the
37:18original
37:18architect
37:18had
37:19intended
37:19them
37:19to
37:20be
37:20so
37:20he
37:21just
37:21came
37:21in
37:21and dug
37:22this
37:22out
37:22and
37:23he
37:23dug
37:23down
37:24about
37:25one and a
37:25half
37:26two meters
37:27down
37:27and this
37:28is the wall
37:29of the
37:29cotino
37:30what he
37:31didn't
37:31realize
37:32was that
37:33the water
37:33table
37:34is about
37:34here
37:35so there's
37:37a lot
37:37of water
37:37behind
37:38this wall
37:39and under
37:39the foundations
37:40and as he
37:41dug this
37:42cotino
37:42out
37:43the water
37:44came spouting
37:45out of the
37:46ground
37:46and
37:47the tower
37:49moved
37:49the top
37:50of the tower
37:50moved
37:51about half
37:51a meter
37:52it lurched
37:53literally
37:53this way
37:54it's amazing
37:56that it
37:57didn't fall
37:57over
37:58there was
38:11more agony
38:12in the
38:121930s
38:14Benito
38:19Mussolini
38:19leader of the
38:20fascists
38:21had become
38:22dictator
38:22in Italy
38:23his regime
38:25rejected
38:26the drooping
38:26tower
38:27as an
38:28inappropriate
38:28symbol
38:29engineers
38:33were ordered
38:34to sort out
38:35the troublesome
38:35lean
38:36a plumb line
38:39was installed
38:40to measure it
38:41in thousands
38:42of a degree
38:42but below
38:45ground
38:46the engineers
38:47wreaked
38:48havoc
38:48they drilled
38:51holes
38:51through the
38:52floor
38:52of the
38:53tower
38:53and almost
38:56200 tons
38:57of concrete
38:58were poured
38:58into the
38:59foundations
38:59the new
39:03plumb line
39:03recorded a
39:04southward
39:04lurch
39:05of nearly
39:06a tenth
39:06of a degree
39:07the work
39:10had destabilized
39:11the delicate
39:12tower
39:12in the
39:191950s
39:20the seven
39:21swaying
39:22medieval
39:22bells
39:23were locked
39:24tight
39:24their
39:29vibrations
39:30had been
39:31shaking
39:31the tower
39:31apart
39:32so precarious
39:37was the
39:38condition
39:38of the
39:38tower
39:39that even
39:40its bells
39:41could tip
39:41the balance
39:42an object
39:45lesson
39:45that even
39:45today
39:46must be
39:46taken
39:47to heart
39:47when
39:50anybody
39:51has tried
39:51to do
39:52anything
39:52on the
39:52south
39:53side
39:53the tower
39:54has always
39:55said
39:55don't touch
39:56me
39:56I'm
39:57very
39:57very
39:57delicate
39:58and
39:59it's
39:59moved
39:59so the
40:00tower
40:01has actually
40:01spoken
40:01to us
40:02through
40:02the
40:03way
40:03that
40:03it's
40:03moved
40:04caution
40:09is
40:09wise
40:10but
40:11visitors
40:11grow
40:12impatient
40:12peace's
40:17tourist
40:17industry
40:18appears to
40:18be
40:18struggling
40:19eventually
40:24the
40:25continuing
40:25threat
40:26of an
40:26earthquake
40:26and the
40:27hideous
40:28lead
40:28ingots
40:28trigger
40:29a major
40:30political
40:31shift
40:31and the
40:32green light
40:33is given
40:33to a
40:33high-risk
40:34proposal
40:35the
40:35committee
40:36would like
40:37first
40:37to remove
40:38the lead
40:39waste
40:39and to
40:40substitute
40:41them
40:41with
40:42invisible
40:43cables
40:44in the
40:44soil
40:45giving
40:46the same
40:46effect
40:47in
40:49this
40:50plan
40:50anchors
40:51will be
40:51attached
40:52to a
40:52concrete
40:52ring
40:53wrapped
40:53around
40:53the
40:54base
40:54of
40:54the
40:54tower
40:54the
40:56engineers
40:57will
40:57drill
40:57through
40:58the
40:58soft
40:58soil
40:59and
40:59secure
41:00the
41:00anchors
41:00in
41:01the
41:01solid
41:01bedrock
41:02130
41:03feet
41:03down
41:04the
41:05pull
41:05from
41:05the
41:06anchors
41:06will
41:07replace
41:07the
41:07push
41:08of
41:08the
41:08unattractive
41:09lead
41:09weights
41:10this
41:12operation
41:13will
41:13not
41:13reverse
41:14the
41:14lean
41:14but
41:15should
41:16halt
41:16and
41:16stabilize
41:16it
41:17the
41:19contractors
41:19first
41:20attempt
41:20to
41:21install
41:21the
41:21ring
41:22through
41:22which
41:23the
41:23anchors
41:23will
41:23be
41:24connected
41:24to
41:24the
41:24tower
41:25made
41:26of
41:26reinforced
41:27concrete
41:28the
41:28ring
41:28is
41:29positioned
41:29under
41:29the
41:30floor
41:30of
41:30the
41:30catino
41:31well
41:31beneath
41:32the
41:32water
41:32table
41:33this
41:37is
41:37a
41:37major
41:38gamble
41:38now
41:41we
41:41are
41:41very
41:42nervous
41:42yes
41:43we
41:43have
41:44always
41:44been
41:44very
41:44nervous
41:45when
41:45we
41:45did
41:46any
41:46intervention
41:47on
41:47this
41:48tower
41:49because
41:50the
41:50tower
41:50is
41:51reacting
41:53in
41:54a
41:55way
41:55which
41:55is
41:56not
41:56always
41:57the
41:58way
41:58we
41:58expect
41:59as
42:01the
42:02contractors
42:02burrow
42:03down
42:03they
42:05inject
42:06liquid
42:06nitrogen
42:06at a
42:07temperature
42:08of about
42:08200
42:09degrees
42:09below
42:09zero
42:10into
42:10the
42:11ground
42:11this
42:17freezes
42:18the
42:18surrounding
42:18groundwater
42:19so that
42:20it
42:20cannot
42:21flood
42:21the
42:21excavation
42:22during
42:26during the
42:26freezing
42:26opera
42:27president
42:28ranieri
42:28favili
42:29all too
42:30familiar
42:31with the
42:31consequences
42:32of past
42:32interventions
42:33gets
42:34carried away
42:35by an
42:35overactive
42:36imagination
42:37there
42:39was a
42:43period
42:43in which
42:44to tell
42:44the truth
42:45i
42:45imagined
42:46i heard
42:46some
42:46noises
42:47that were
42:47a little
42:48strange
42:48during
42:49the night
42:49i can't
42:50say
42:50i didn't
42:51worry
42:51about
42:51this
42:52unfortunately
42:53it's
42:54inevitable
42:54because
42:55first of
42:55all
42:55i'm
42:56a
42:56peace
42:56secondly
42:57i would
42:58frankly
42:58be
42:58very
42:59unhappy
42:59to go
43:00down
43:00in
43:00history
43:00as
43:01the
43:01opera
43:01president
43:01under
43:02whom
43:02the
43:03tower
43:03fell
43:03as
43:12the
43:13freezing
43:13moves
43:14to the
43:14sensitive
43:14south
43:15side
43:15the
43:16monitors
43:17watch
43:17the
43:17tower
43:17closely
43:18at
43:213 30
43:22a.m
43:22on
43:22the
43:236th
43:23of
43:23september
43:241995
43:24the
43:26tower
43:26reacts
43:27the
43:30top
43:30lurches
43:31a
43:3116th
43:32of
43:32an
43:32inch
43:32south
43:33in
43:34one
43:34night
43:35it
43:35moved
43:35what
43:36it
43:36normally
43:36moved
43:36in
43:37a
43:37year
43:37and
43:38that
43:38worried
43:39us
43:39because
43:39if
43:39that
43:39had
43:39continued
43:40that
43:41would
43:41have
43:41been
43:41very
43:42large
43:42and
43:43the
43:43tower
43:43stability
43:44may
43:44have
43:45been
43:45in
43:45jeopardy
43:46we
43:46knew
43:46that
43:47the
43:47tower
43:47was
43:48moving
43:48was
43:48responding
43:49in
43:50a
43:51special
43:51way
43:51and
43:52we
43:54decided
43:55to
43:55stop
43:55the
43:55work
43:56contractors
43:59scramble
43:59to
44:00restabilize
44:00the
44:01tower
44:01by
44:01loading
44:02on
44:02more
44:02leading
44:03the
44:04lurch
44:04is
44:04halted
44:05but
44:05the
44:06committee's
44:06attempt
44:06to
44:07remove
44:07the
44:07ugly
44:08lead
44:08has
44:09resulted
44:09in
44:09an
44:09even
44:10larger
44:10pile
44:11around
44:11the
44:11tower's
44:11base
44:12this
44:16committee
44:16what
44:17has
44:17it
44:17done
44:17intervened
44:19basically
44:19in that
44:20same
44:20highly
44:20delicate
44:21zone
44:21where
44:21Gerardesca
44:22had
44:22intervened
44:23and
44:23all
44:23they
44:24did
44:24is
44:24bring
44:24the
44:24tower
44:25closer
44:25to
44:25collapse
44:26so
44:27there
44:27you
44:27are
44:28they've
44:28been
44:29working
44:29for
44:29several
44:29years
44:30which
44:30is
44:30too
44:31long
44:31and
44:32now
44:32they've
44:32left
44:32the
44:32tower
44:33in a
44:33worse
44:33condition
44:34than
44:34they
44:34found
44:34one
44:43would
44:43believe
44:43if
44:43one
44:44were
44:44of
44:44a
44:44late
44:4520th
44:45century
44:46technocratic
44:46mentality
44:47or
44:48just
44:48simply
44:48have
44:48a
44:48faith
44:49in
44:49science
44:49well
44:50we
44:50know
44:50so
44:51much
44:51why
44:51can't
44:52we
44:52come
44:52up
44:52with
44:52a
44:52solution
44:53to
44:53the
44:53problem
44:53but
44:54there
44:54may
44:54be
44:55in
44:55fact
44:55no
44:55solution
44:56the
44:57building
44:58site
44:58around
44:58the
44:59tower
44:59lies
45:00quiet
45:00for
45:01a
45:01year
45:02after
45:02what
45:02becomes
45:03known
45:03as
45:03Black
45:04September
45:04then
45:06in
45:06late
45:061996
45:07because
45:08of
45:09a
45:09dispute
45:09within
45:09the
45:10Italian
45:10government
45:10the
45:12committee
45:12is
45:13disbanded
45:14Berlin's
45:17extensive
45:17research
45:18now
45:19looks like
45:19it has
45:20been
45:20a
45:20wasted
45:20effort
45:21it's
45:22been
45:22very
45:22frustrating
45:23a
45:24lot
45:24of
45:25my
45:25friends
45:25say
45:26to
45:26me
45:26how
45:26can
45:26you
45:26possibly
45:27stand
45:28the
45:30way
45:30this
45:30has
45:30gone
45:30on
45:31and
45:31on
45:31on
45:31why
45:32don't
45:32you
45:32just
45:33resign
45:33it
45:33would
45:33be
45:34so
45:34much
45:34easier
45:34but
45:35it's
45:35so
45:36important
45:36to
45:37the
45:37life
45:38of
45:38the
45:38tower
45:38that
45:39we
45:39do
45:39something
45:39soon
45:40the
45:41committee
45:42remains
45:42out of
45:42action
45:43until the fall
45:44of 97
45:45just
46:00just north
46:01of
46:01Pisa
46:01the area
46:02around
46:03Assisi
46:03birthplace
46:04of
46:04St.
46:04Francis
46:05is hit
46:06by an
46:06earthquake
46:07measuring
46:08almost
46:08six
46:09on the
46:09Richter
46:09scale
46:10thousands
46:11are left
46:12homeless
46:12unique
46:15unique
46:15historic
46:16buildings
46:16are
46:16damaged
46:17beyond
46:17repair
46:18it
46:21soon
46:21emerges
46:22that
46:22although
46:22this
46:23earthquake
46:23was no
46:23surprise
46:24little
46:25was done
46:25to prepare
46:26for it
46:27the
46:29resulting
46:30scandal
46:30inspires
46:31a new
46:31dynamic
46:32attitude
46:32in
46:33Italian
46:33restoration
46:34and
46:34conservation
46:35in
46:38Pisa
46:38the
46:39committee
46:40reconvenes
46:41and
46:42approves
46:42soil
46:43extraction
46:44now
46:46we're
46:46faced
46:46with
46:46the
46:46reality
46:47of
46:48doing
46:48something
46:48on
46:49the
46:49tower
46:50for
46:50the
46:50first
46:51time
46:51something
46:52very
46:52delicate
46:52and
46:53something
46:54that
46:54we
46:54hope
46:54will
46:55provide
46:56the
46:56final
46:56solution
46:57but
47:02there
47:02is
47:02no
47:02margin
47:03for
47:03error
47:03so
47:05the
47:05engineers
47:05on
47:06the
47:06committee
47:06devise
47:07one
47:07of
47:07the
47:07strangest
47:08contraptions
47:08in this
47:09bizarre
47:09story
47:10a hundred
47:13yards
47:13north
47:14of the
47:14tower
47:14just
47:15behind
47:15the
47:15opera
47:15contractors
47:17begin
47:17work
47:18this
47:24this
47:24is
47:24one
47:24of
47:24two
47:25tripods
47:25designed
47:26to
47:26hold
47:27steel
47:27cables
47:27that
47:28will
47:28run
47:28right
47:29across
47:29the
47:29piazza
47:30to
47:32brackets
47:33on
47:33the
47:33tower
47:33second
47:34story
47:34cables
47:39will
47:40form
47:40a
47:40massive
47:40harness
47:41to
47:42support
47:42the
47:42tower
47:43the
47:46harness
47:47is
47:48a
47:48temporary
47:49safeguard
47:50structure
47:51it's
47:52there
47:53to
47:53make
47:53quite
47:54certain
47:54that
47:54if
47:55something
47:55goes
47:56wrong
47:56we
47:57can
47:57control
47:57it
47:58it's
47:59only
47:59temporary
48:00it'll
48:00only
48:00be
48:00there
48:01when
48:01we're
48:01operating
48:02on
48:02the
48:02tower
48:03during
48:05an
48:05unsettling
48:06deluge
48:07the
48:07first
48:08cable
48:08of
48:08the
48:08harness
48:09is
48:09craned
48:09into
48:10position
48:10although
48:14only
48:14temporary
48:15this
48:16is
48:16a
48:16huge
48:16project
48:17just
48:21ten
48:21yards
48:21of
48:22this
48:22cable
48:22weighs
48:23half
48:23a
48:23ton
48:23if
48:27it
48:27lashes
48:27out
48:28from
48:28the
48:28crane
48:28it
48:29could
48:29kill
48:29the
48:30workman
48:30and
48:30damage
48:31the
48:31fragile
48:31tower
48:32at a
48:45critical
48:45moment
48:45the
48:46cable
48:47slips
48:47and
48:48jams
48:48into
48:48a
48:48marble
48:49arch
48:49locals
48:59come
49:00out
49:00to
49:00watch
49:00and
49:01hope
49:02that
49:02the
49:02tower
49:02will
49:02not
49:03overreact
49:03hours
49:07later
49:07the
49:08struggle
49:08to
49:08free
49:09the
49:09cable
49:09is
49:09successful
49:10that
49:17night
49:18the
49:18first
49:19component
49:19of the
49:19harness
49:20is
49:20secured
49:21the
49:34completed
49:34harness
49:34is
49:35carefully
49:35balanced
49:36and
49:36adjusted
49:37it
49:38looks
49:38like
49:38heavy
49:38engineering
49:39there's
49:41only
49:41enough
49:41force
49:42exerted
49:42on
49:42the
49:43tower
49:43to
49:44resist
49:44a
49:44minor
49:45mishap
49:45the
49:46harness
49:47is
49:47not
49:47intended
49:47to
49:48stop
49:49a
49:49catastrophic
49:51failure
49:51it's
49:52not
49:52for that
49:52at
49:52all
49:53it's
49:53simply
49:53to
49:54hold
49:54the
49:54tower
49:54gently
49:55if
49:56the
49:57movements
49:57of the
49:57tower
49:58are
49:58unexpected
49:59the
50:07scene
50:07is
50:07set
50:08and
50:09the
50:09soil
50:09extraction
50:10is
50:10put
50:10to
50:10the
50:10test
50:11we have
50:28just
50:28started
50:29soil
50:30extraction
50:30the
50:33drill
50:34is
50:34about
50:34five
50:35metres
50:35below
50:36ground
50:36level
50:36and
50:38then
50:38the
50:38soil
50:39extraction
50:39takes
50:40place
50:40beneath
50:41the
50:42floor
50:42of
50:42the
50:42cotino
50:43and
50:44the
50:45effect
50:45extends
50:46out
50:47as we
50:48take
50:48the
50:48soil
50:48out
50:49the
50:49effect
50:49of
50:50it
50:50extends
50:50under
50:51the
50:51tower
50:51the
50:54success
50:54of
50:55soil
50:55extraction
50:55hinges
50:56on
50:56the
50:56assumption
50:57that
50:57the
50:58ground
50:58below
50:58the
50:58tower
50:59is
50:59mainly
51:00silt
51:00on
51:03day
51:04one
51:04soil
51:05begins
51:05to
51:05spew
51:05out
51:06of
51:06the
51:06extractor
51:07casing
51:09but
51:09it
51:09looks
51:09like
51:10clay
51:10not
51:11silt
51:11berlin
51:14is
51:14eager
51:14to
51:15make
51:15an
51:15on
51:15the
51:15spot
51:15analysis
51:16an
51:17experienced
51:18soils
51:19engineer
51:19can
51:20tell
51:20exactly
51:20what
51:21soil
51:21material
51:22is
51:22if
51:24you
51:24just
51:25put
51:25a
51:25grain
51:25or
51:26two
51:26against
51:26your
51:26teeth
51:27you
51:29can
51:29tell
51:29straight
51:30away
51:30that
51:30this
51:31is
51:31actually
51:31a
51:32sandy
51:32silt
51:33it
51:34feels
51:34like
51:34clay
51:35but
51:35it
51:35is
51:35actually
51:35a
51:35sandy
51:36silt
51:36so
51:38it
51:38is
51:38total
51:39confirmation
51:39of
51:40what
51:40we
51:40were
51:40expecting
51:41the
51:45tower
51:45has
51:45been
51:45creeping
51:46south
51:46for
51:46centuries
51:47so
51:48the
51:48lean
51:49will
51:49not
51:49be
51:49reversed
51:50in
51:50a
51:50few
51:50hours
51:51right
51:53now
51:53the
51:53main
51:54fear
51:54is
51:54that
51:54the
51:55drilling
51:55will
51:55trigger
51:56a
51:56catastrophic
51:56lurch
51:57further
51:58south
51:58but
51:59the
52:00tower
52:00is
52:00quiet
52:00and
52:01the
52:02operation
52:02continues
52:03we
52:18have
52:18started
52:19what
52:20could
52:20well
52:20turn
52:21out
52:21to
52:21be
52:21the
52:21final
52:22stabilization
52:22measures
52:23the
52:24result
52:24will
52:25be
52:25that
52:25the
52:25tower
52:25will
52:26be
52:26leaning
52:27at
52:2810%
52:29less
52:29than
52:29it
52:29is
52:29now
52:30and
52:31we
52:31will
52:31have
52:31added
52:32300
52:32years
52:33to
52:33its
52:33life
52:34at
52:34least
52:34and
52:35we
52:35will
52:35have
52:36reduced
52:36the
52:36stresses
52:37in
52:37the
52:37masonry
52:37and
52:39these
52:39have
52:39been
52:39our
52:39prime
52:40objectives
52:40right
52:41from
52:41the
52:41start
52:42of
52:42the
52:42whole
52:42project
52:42after
52:46one
52:46month
52:46of
52:46soil
52:47extraction
52:47the
52:47top
52:49has
52:49moved
52:49a
52:49fifth
52:50of
52:50an
52:50inch
52:50north
52:51but
52:55the
52:55stable
52:56position
52:56of
52:57300
52:57years
52:57ago
52:58lies
52:58another
52:59foot
52:59away
53:00even
53:02if
53:03the
53:03operation
53:03goes
53:04well
53:04it
53:05will
53:05take
53:05about
53:05two
53:06years
53:06to
53:07coax
53:07the
53:07tower
53:08that
53:08far
53:08north
53:09until
53:11then
53:12the
53:13leaning
53:13tower
53:14of
53:14Pisa
53:15will
53:15remain
53:16wired
53:16in
53:16and
53:17strapped
53:17up
53:18like
53:18a
53:18patient
53:18on
53:19the
53:19operating
53:19table
53:20its
53:25progress
53:26will
53:26be
53:26anxiously
53:27watched
53:28lest
53:29this
53:29enigmatic
53:30structure
53:31confronts
53:32us
53:32with
53:32an
53:32unwelcome
53:33surprise
53:34the
53:41leaning
53:41tower
53:42the
53:43statue
53:43of
53:43liberty
53:44windsor
53:45castle
53:46and
53:46the
53:47parthenon
53:47on
53:48nova's
53:49website
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53:50what it
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54:01thrill ride
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54:04than just
54:04fantasy
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54:14other
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54:211-800-255-9424
54:38Nova
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55:58Oh, oh, oh, oh, oh, oh, oh, oh