...we have seized lightning from the skies, but what lies just below us, the earth upon which we tread, where we live and die, is still largely a mystery to us. God forgive my presumption, but I yearn to raise this dark veil, though more vigorous hands than mine have perished and been forced to recognise their impotence.
[From a speech given by the first
director of the observatory, Macedonio Melloni, at the opening
ceremonies in 1845.]
The observatory —now, officially, the Vesuvius Observatory, Naples Section of the National Institute of Geophysics and Volcanology— is visible on the western slopes of Vesuvius. It rests on Colle del Salvatore, a knoll (image, left), putting it out of the range of ejecta and in a position where lava from an eruption is channeled around the observatory and not through and over it. It is the oldest such institution in Italy and is still an active institution for important research in geophysics and volcanology. The old observatory is primarily a museum. The newer observatory monitors the volcano it and also keeps tabs on other geological happenings in the area, such as those at the nearby Flegrean Fields and the island of Ischia.
We note the importance of Luigi Palmieri (1807–1896),an Italian physicist and meteorologist. He was famous for his scientific studies of the eruptions of Mount Vesuvius, for his researches on earthquakes and meteorological phenomena and for improving the seismograph of the time. Palmieri was born near Benevento, Italy and died in Naples at the age of 89. Palmieri received a degree in physics from the University of Naples. In 1845, he was made Professor of Physics at the Royal Naval School in Naples and in 1847 was appointed Chair of Physics at the university. In 1848, he began working at the Vesuvius Observatory and in 1854 was appointed as Director of the Observatory. Using an electromagnetic seismometer for the detection and measurement of ground tremors, Palmieri was able to detect very slight movements in trying to predict volcanic eruptions. Furthermore, he was the first to detect the presence of Helium on Earth on the lava of Mount Vesuvius. The impact crater, Palmieri, on the Moon is named for him. Off-site the Scientific American has a fine article on him here:
(My thanks to Jeff Miller for pointing that article out to me.)
(this section, below, was revised, August 2023)
In 1970 the original building became a museum, exhibit hall, and library. A new building, the white structure below it met the needs of modern science. One directors was the best-known Italian geologist, Giuseppe Mercali (director from 1911-14). He devised the scale to classify quakes by effect on the environment.
There are two ways to describe a quake: a magnitude scale or an intensity scale. The first tells you how much energy was released in 'magnitude" - say, 'Magnitude 4.8'. It is of interest to scientists, who know the numbers. The other scale is the one devised by Mercali for Italy, an intensity scale. It is useful for the average person.
There is now (2023) a European macroseismic scale (EMS) to evaluate seismic intensity in European countries and is also used in a number of countries outside Europe. Issued in 1998 the scale is called EMS-98. It runs as follows:
- I. Not felt Not felt by anyone.
- II. Scarcely felt. Felt only by people at rest in houses, especially on upper floors of buildings.
- III. Weak The vibration is weak and is felt indoors by a few people. People at rest feel swaying or light trembling. Noticeable shaking of many objects.
- IV. Largely observed The earthquake is felt indoors by many people, outdoors by a few. A few people are awakened. The level of vibration is possibly frightening. Windows, doors and dishes rattle. Hanging objects swing. No damage to buildings.
- V. Strong The earthquake is felt indoors by most, outdoors by many. Many sleeping people awake. A few run outdoors. Entire sections of all buildings tremble. Most objects swing considerably. China and glasses clatter together. The vibration is strong. Top-heavy objects topple over. Doors and windows swing open or shut.
- VI. Slightly damaging Felt by everyone indoors and by many to most outdoors. Many people in buildings are frightened and run outdoors. Objects on walls fall. Slight damage to buildings; i.e, fine cracks in plaster and small pieces of plaster fall.
- VII. Damaging Most people are frightened and run outdoors. Furniture is shifted and many objects fall from shelves. Many buildings suffer slight to moderate damage. Cracks in walls; partial collapse of chimneys.
- VIII. Heavily damaging Furniture may be overturned. Many to most buildings suffer damage; chimneys fall; large cracks appear in walls and a few buildings may partially collapse. Can be noticed by people driving cars.
- IX. Destructive Monuments and columns fall or are twisted. Many ordinary buildings partially collapse and a few collapse completely. Windows shatter.
- X. Very destructive Many buildings collapse. Cracks and landslides can be seen.
- XI. Devastating Most buildings collapse.
(this section was revised, August 2023)
- XII. Completely devastating.
published by the observatory tells us that
...there is a shift system to ensure that two staff members are always on duty at the Vesuvius Observatory. These operators checking seismic developments of the Campania volcanic areas...and for communicate to the authorities any significant phenomena observed by the seismic monitoring system, under permanent observation.
This is good to know since hundreds of thousands of people live in the immediate area described as the "Red Zone", the area that will have to be evacuated when (not if) the time comes. A recent report from 32nd World Geological Conference in Florence essentially said that an explosive eruption (not a slow, effusive, what-a-lovely-lava-flow! eruption, but a true explosion) was just a matter of time. The report described Vesuvius as the world's most dangerous volcano and warned that by 2100, Mount Vesuvius will certainly repeat its most dramatic performance, the infamous eruption of 79 A.D., which buried Pompeii.
moments in the history of the Vesuvius observatory
have included an episode in 1872 in which director,
Luigi Palmieri, stayed at his
post during a large eruption in order to make accurate
observations. That eruption killed a group of students
taken by surprise by a sudden burst from
a cone on the northwest slope. Palmieri stayed
while the lava flowed dangerously close. He survived
and continued to edit his Vesuvius Observatory Annals, a
prestigious journal that he founded and edited until
his death in 1896. There was a powerful eruption in
April, 1906 and one in 1944 (photo, above), accurately
predicted, by the way, by the director at that time,
Giuseppe Imbò, who added the newest scientific tools
at the observatory. The institution continues to keep
abreast of the latest monitoring techniques in order
to prepare for whatever dramatic events lie ahead.
[Also see this New York
Times article from 1906,
praising the role of Raffaele Matteucci, the director of
the observatory during the powerful eruption of that
[Also see "Recent Eruptions of
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