Design
of casa baraccata bracing,
from
Vivenzio's Istoria de' Tremuoti (1783)

The
Earthquake of 1783 and the Rebuilding of Calabria
An early example of
earthquake-resistant construction and
modern urban
planning
The massive earthquake in Lisbon in 1755 produced a
striking piece of anonymous verse:
With her last earthquake this round world
shall rise,
The sun shall lose his
fires in endless night,
And the moon turned to
blood, glare horrid light,
When comets dire shall
sweep athwart the sky,
And stars like leaves
before the tempest fly.
That horrible event brought comments from Voltaire,
Rousseau, and even Kant, who opined that people should
stop blaming such things on a wrathful god and worry more
about putting up houses that can withstand earthquakes. (A
wise man, old Manny.) And so, after all was said and done,
the Lisbon quake, indeed, produced a new kind of
construction, gaiola
pombalina (Pombaline cage, named for the Marquês
de Pombal, instrumental in rebuilding Lisbon) —that is,
masonry reinforced with an internal wooden cage.
Lisbon was a major
historic capital and one of the most beautiful cities in
Europe; thus, news of the earthquake spread fast (for
those days!) and was the focus of attention throughout the
Continent. On the other hand, the calamitous earthquakes
that struck Calabria in the southern region of the Kingdom
of Naples in 1783 were in an area so remote that news of
the disaster took nine days to reach the royal palace in
the capital city, Naples, a few hundred miles to the
north.
The first of five major quakes struck on February
5, 1783, but later research revealed that the entire
region had been hit by a series of quakes lasting through
1787. All in all, 949 major and minor quakes hit Calabria.
Around 200 cities and towns were destroyed. The estimated
number of deaths ranges from 32,000 to 50,000. The very
landscape of Calabria was changed as new valleys and lakes
were created. Pietro Colleta, a prominent Neapolitan
historian from the time, wrote in his Storia del Reame di Napoli
[History of the Kingdom of Naples],
“Nothing remained of the old forms; lands, cities,
roads, signs vanished…Many works of nature and man,
built over the centuries…were gone in a moment."
Much of the history of the Kingdom of Naples in the
1700s tends to be overwhelmed by later political events
leading up to the unification of Italy (1860). Certainly
there does not seem to be an awareness even in Calabria
today of the major natural catastrophes in the 1780s (in
the way, for example, that Portuguese still remember the
1755 event). The Calabrian calamity, as far as I know,
produced no dramatic poetry. (The good news is that it
certainly produced no
Neapolitan counterpart of the earlier Lisbon episodes of
people being burned at the stake to appease the Lord! (*note)
The Calabrian disaster did, however, produce some things
that are noteworthy in the history of science, engineering
and urban planning. The Bourbon government sent out a
research team from the Neapolitan Academy of Science and
Letters and quickly published a remarkable work, Istoria de' fenomeni del
tremoto avvenuto nelle Calabrie e nel Valdemone
nell'anno 1783 [Account of the Effects of the
Earthquake in Calabria in 1783] (see this link). The catastrophes thus led to
innovation in architecture and construction. Tobriner
(sources, below) writes:
Much
of the original work was written up by the royal
physician, Giovanni
Vivenzio, in Istoria
de' Tremuoti (1783).
The work contains a diagram of the anti-seismic casa baraccata
system of construction (top photo), detailing how it is
different from the gaiola
system used in Portugal 30 years earlier. (From Tobriner
2, sources, below):
The system works upon the basic principle that
the masonry structure is tied together by an internal
wooden framework. But whereas the lateral resistance of
the gaiola is in the internal walls, the lateral
resistance in the casa baraccata is in the
external walls...The Bourbon government...introduced a
system of construction to minimize future damage and to
save lives. The building system, called la casa
baraccate, was based on the sophisticated notion
that structures must respond to seismic disturbances as
units. The system was based on an internal framework of
wood members embedded in the rubble construction which
was common in Calabria. Height limitations, foundations,
and special "x" bracing to counter lateral forces were
also part of the system that was invented in Calabria
and promulgated as the construction code of 1785. It
represents one of the earliest concerted responses to
earthquake danger and one which was lauded by early
20th-century engineers as a practical means of providing
safe construction in earthquake country.
The casa baraccata
and the new building code of 1785 that came out of the
work of Vivenzio and others represent the first
anti-seismic system in Europe prescribed by code for an
entire region. Numerous new towns were built to the new
1785 building code, including the town of Filadelfia (to
replace the ruined town of Castelmonardo). Filadelfia, in particular,
was an attempt to create an ideal community (perhaps
somewhat like the earlier social experiment by Charles III
to create a perfect rural community at San Leucio in 1750).
Filadelfia and other towns were built or rebuilt with the
Cassa Sacra,
funds appropriated from the Catholic church (note 2). The
Bourbon state limited the number of churches that a new
town could have (and even forbade church steeples!); the
streets were laid out symmetrically and the buildings were
uniform.
Seminara,
rebuilt according to the
new
building code of 1785.
The
modern Italian region of Calabria has five provinces
as indicated (map, above). Filadelfia is in the smallest
province, Vito Valentia. Of the many towns rebuilt or
built new after the 1783 earthquakes, a few stand out as
having been done to the regulations of the new building
code, which specified (according to population) how wide
main and secondary streets should be, how tall the
buildings could be, etc. etc. Also, some effort was made
to save historic structures that had not been totally
destroyed by the quakes. These towns are Bianco (RC),
Seminara (RC), Mileto (VV), Gallina (RC), Cortale (Cat),
Bagnara (RC), and, as noted, Filadelfia (VV). They and
others all have things in common: they are all relatively
small in population (Calabria was a great exporter of
human beings during the Neapolitan diaspora
of the late 1800s and early 1900s), and even today there
is something modern about these towns from the late 18th
century in that there is no medieval clutter, there is a
main square, and there are straight streets. All of that
is the result of having been part of the first massive
effort in European history to build not just single
buildings, but entire towns that could withstand the
seismic forces of nature and then to re-incorporate an
entire region back into a modern nation state.
[Also see this link on Pompeo
Schiantarelli, whose engravings documented much of
the damage from the earthquakes.]
notes:
1. In Candide
(1759), Voltaire wrote, “After the earthquake, which had
destroyed three-fourths of the city of Lisbon, the sages
of that country could think of no means more effectual to
preserve the kingdom from utter ruin than to entertain the
people with an
auto-da-fé, it having been decided by the
University of Coimbra, that the burning of a few people
alive by a slow fire, and with great ceremony, is an
infallible preventive of earthquakes.” In fairness,
Voltaire's buddy, Rousseau, accused him of being unduly
cynical and snide. Cynical? Snide? Who, Voltaire!?(^back)
2. The town of Filadelfia apparently comes
to its interesting name from the fact that the bishop of
nearby Potenza at the time was Giovanni Andrea Serrao. He
was born in Castelmnonardo and was a great promoter of
building a new town to replace his birthplace, now
destroyed. He also thought it would be a good idea if
citizens remembered their Greek origins and lived in a
place the name of which would remind them to love each
other and all humanity ("phila-delphia"= a compound of philos (φίλος)
"loving", and adelphos
(ἀδελφός) "brother"). AND—very
important—Serrao had been corresponding with a
resident of the other City of Brotherly Love, Benjamin
Franklin! (^back)
sources:
-Tobriner,
Stephen. "La Casa Baraccata: Earthquake-Resistant
Construction in 18th-Century Calabria," in Journal of the Society of
Architectural Historians, Vol. 42, No. 2.
Pub. by U. of California Press (May,
1983).
-Tobriner, Stephen. "Safety and Reconstruction
After the Sicilian earthquake of 1693--the
Eighteenth-Century Context" in Dreadful
Visitations: Confronting Natural catastrophe in the Age of
Enlightenment by Alessa Johns, Routledge,
1999.
-Principe, Ilario. Città
nuove in Calabria nel tardo Settecento [New
Cities in Calabria in the Late 1700s]. Chiaravalle
Centrale (CZ), 1976.
-unsigned .pdf file online here: Le Città della Calabrie
Ricostruite dopo il Terremoto del 1783. Retr.
Sept. 4, 2011.
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