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Benvenuti in queste pagine dedicate a scienza, storia ed arte. Amelia Carolina Sparavigna, Torino

Monday, January 24, 2011

Archimedes's steam cannon

A steam cannon is a cannon where projectiles are launched by steam. The first steam cannon was designed by Archimedes during the Siege of Syracuse. Leonardo da Vinci was also known to have designed one. The device is metal tube, which would be placed in a furnace: one end of the tube is closed and the other loaded with a projectile. Once the tube reached a high enough temperature, a small amount of water in injected in behind the projectile. Leonardo da Vinci guessed that the water would rapidly expand into vapour, blasting the projectile out the front of the barrel.
See how the  ArchiMITes cannon is working: http://web.mit.edu/2.009/www//experiments/steamCannon/ArchimedesSteamCannon.html

Thermal water pump

A water pump that uses thermal energy from the sun is to undergo field testing before potentially being used by farmers in the developing world for irrigating fields. The device uses a non-inertive-feedback thermofluidic engine (NIFTE) that converts relatively small temperature differences between its heat source and heat sink into mechanical force.
Thermal water pump could aid farmers in developing nations | News | The Engineer
NIFTE is the core product of an univerisyt spin-off, http://www.thermofluidics.com/ . It would be interesting to have more details.

Thermodynamic solars: a new italian technology

"Encouraging news in the renewable energy come from solar thermal industry that, in 2009, has experienced considerable growth and that seems destined to play an even more important in coming years. The U.S., in fact, intend to achieve by 2020 the technology for new power plants with a total capacity of 10.3 GW of power.
Also Italy is taking decisive steps in this field, as evidenced by the recent birth of a company called Archimedes Solar Energy, which produces the key component of solar thermal power plants, pipes receptors, according to a new technology patented by ENEA." World of Solar Thermal - Solar Thermal Energy Daily News, Events, Companies, Products, Jobs and more - Thermodynamic solars: a new italian technology

Why the name "Archimedes"? Let us remember what the 2nd century AD author Lucian wrote about.
"During the Siege of Syracuse (c.214–212 BC), Archimedes destroyed enemy ships with fire. Centuries later, Anthemius of Tralles mentions burning-glasses as Archimedes' weapon. The device, sometimes called the "Archimedes heat ray", was used to focus sunlight onto approaching ships, causing them to catch fire. This purported weapon has been the subject of ongoing debate about its credibility since the Renaissance. René Descartes rejected it as false, while modern researchers have attempted to recreate the effect using only the means that would have been available to Archimedes. It has been suggested that a large array of highly polished bronze or copper shields acting as mirrors could have been employed to focus sunlight onto a ship. This would have used the principle of the parabolic reflector in a manner similar to a solar furnace." More  wiki

Wind turbines need more studies

Wind turbines need to be farther apart, suggests study | News | The Engineer
"Currently, turbines on large wind farms are spaced about seven rotor diameters apart. The new spacing model developed by Meneveau and Johan Meyers, an assistant professor at Katholieke Universiteit Leuven in Belgium, suggests that placing the wind turbines 15 rotor diameters apart - more than twice as far apart as in the current layouts – results in more cost-efficient power generation. Large wind farms - consisting of hundreds or even thousands of turbines - are planned or already operating in the western United States, Europe and China."

Friday, January 21, 2011

Museo in 3D


Dettaglio di una scultura indiana, da vedere in 3D con gli occhialini rosso/ciano.
Museo Arte Orientale

Profiles - Chief Joseph

Chief Joseph (1840 – 1904) was the chief of the Wallowa band of Nez Perce during General Oliver O. Howard's attempt to forcibly remove his band and the other "non-treaty" Nez Perce to a reservation in Idaho. For his principled resistance to the removal, he became renowned as a humanitarian and peacemaker.
From Wiki
Joseph the Younger succeeded his father as chief in 1871. Before his death, the latter counseled his son:
"My son, my body is returning to my mother earth, and my spirit is going very soon to see the Great Spirit Chief. When I am gone, think of your country. You are the chief of these people. They look to you to guide them. Always remember that your father never sold his country. You must stop your ears whenever you are asked to sign a treaty selling your home. A few years more and white men will be all around you. They have their eyes on this land. My son, never forget my dying words. This country holds your father's body. Never sell the bones of your father and your mother." Chief Joseph commented "I clasped my father's hand and promised to do as he asked. A man who would not defend his father's grave is worse than a wild beast."
...
Chief Joseph formally surrendered to General Nelson Appleton Miles on October 5, 1877 in the Bear Paw Mountains of the Montana Territory, less than 40 miles south of Canada in a place close to the present-day Chinook in Blaine County. The battle is remembered in popular history by the words attributed to Chief Joseph at the formal surrender:
"Tell General Howard I know his heart. What he told me before, I have it in my heart. I am tired of fighting. Our chiefs are killed; Looking Glass is dead, Too-hul-hul-sote is dead. The old men are all dead. It is the young men who say yes or no. He who led on the young men is dead. It is cold, and we have no blankets; the little children are freezing to death. My people, some of them, have run away to the hills, and have no blankets, no food. No one knows where they are—perhaps freezing to death. I want to have time to look for my children, and see how many of them I can find. Maybe I shall find them among the dead. Hear me, my chiefs! I am tired; my heart is sick and sad. From where the sun now stands, I will fight no more forever."


The image shows Alice Cunningham Fletcher and Chief Joseph at the Nez Percé Lapwai Reservation in Idaho, where Fletcher arrived in 1889. The image is adapted from the original photograph by Jane Gay. This image is in the public domain due to its age.

Alice Cunningham Fletcher (1838 - 1923) was an American ethnologist who studied and documented American Indian culture. More  Wiki and also http://www.nmnh.si.edu/naa/fletcher/ (this web page has an image archive with original stereoscopic pictures).

Thursday, January 20, 2011

Caligula's Tomb

"Hallan la tumba de Calígula", Tras dos milenios de su muerte, hallaron la tumba del emperador Gaius Julius Caesar Augustus Germanicus, más conocido como Calígula, de quien se decía que era promiscuo, depravado, cruel y demente, en el sur de Roma. El lugar fue detectado cuando la policía descubrió a un hombre que trataba de contrabandear una estatua del emperador robada del sitio, de dos metros y medio de alto. Calígula murió a los 28 años, cuando sus propios guardaespaldas acabaron con su vida en el año 41 A.C. Una de las locuras más célebres de Calígula fue nombrar consejero y sacerdote a su caballo favorito, Incitatus. http://connuestroperu.com/index.php?option=com_content&task=view&id=14915&Itemid=1

"Caligula's tomb found after police arrest man trying to smuggle statue"
Police arrest tomb raider loading part of 2.5 metre statue into lorry near Lake Nemi, south of Rome, where Caligula had a villa. The Guardian, http://www.guardian.co.uk/world/2011/jan/17/caligula-tomb-found-police-statue   The lost tomb of Caligula has been found, according to Italian police, after the arrest of a man trying to smuggle abroad a statue of the notorious Roman emperor recovered from the site. ...  The emperor had a villa there, as well as a floating temple and a floating palace on the Lake Nemi.

La tomba perduta di Caligola è stata trovata, secondo la polizia italiana, dopo l'arresto di un uomo che cercava di contrabbandare all'estero una statua dell'imperatore romano famigerato recuperata dal sito.


Emperor Caligula, Ny Carlsberg Glyptotek. (courtesy, Louis le Grand)

Caligula's Floating Palaces


"Caligula was a man of many passions, and he indulged nearly all of them, including his passions for chariot racing, theatrical performances, gladiatorial games, and ships. During his brief rule from A.D. 37 to 41, he had two enormous ships--a sailing ship and an oared galley--built and anchored on Lake Nemi as pleasure craft. Pillaged and deliberately sunk later in the first century, they were recovered in a feat of engineering sponsored by Benito Mussolini in the 1930s, but destroyed during a German retreat in 1944."  http://www.archaeology.org/0205/abstracts/caligula.html

Here an interesting description, written by Colonel Maceroni, in 1838.

A very singular piece of antiquity exists in the lake of Nemi, of which I have never seen any mention made by travellers. On the north-east side of the lake, in about forty feet water, lie the ruins of a large floating palace constructed by the Emperor Claudius or by Nero (in fact, Caligula). The lakes of Albano and Nemi are the craters of extinct volcanos, from which, at the time when they were covered by the sea, has proceeded all that vast quantity of tuffo and puzzolana which covers the Campagna di Roma. The high, steep banks of these circular lakes, covered with most beautiful trees and villas, cause one side of the water below to be constantly sheltered from the wind. Hence a floating habitation will give the choice of shade and shelter, or sunshine as the season may require. The way in which I became acquainted with this sunken palace was quite accidental. Being one evening in my punt about to lay some eel lines, the fisherman whom I employed told me, that the best place in that vicinity was "about the old palace". I stared and looked about. "What palace?" said I. I see plenty of houses and cottages, and ruins, on the hills around, but they are not even quite at the water's edge. My man rejoined : "I mean about the wooden palace under water in which the Emperor Claudius used to live." Delighted and excited by this announcement more than I should have been by the capture of a thousand eels as big as the mast of a ship, I hastened to the spot, but the declining sun had sunk below the high crater wood-clothed margin of the lake, and looking down into the limpid waters, all seemed dark and blue, and nothing could be seen but the hills and trees, and my own anxious physiognomy reflected in the watery mirror. However, I laid my lines, the hooks being baited with the thighs of frogs, and next morning I found fourteen eels, all about a pound a piece, and some of three pounds weight. Moreover, a brilliant sunshine enabled me to see the sunken palace, which appeared to be about one hundred feet square and fifteen to twenty feet high. How did I then regret not having the command of a diving-bell! What most curious and precious objects of antiquity might not be found in the interior of this construction? But this discovery I must leave to some future traveller, who may have the means of causing a diving-bell to be constructed at Rome, and know how to use it. As for myself, I mentioned the discovery to General Miolis, the imperial locum tenens, or Governor of Rome, and also to the learned antiquary, Mr. Norviuse de Monbreton, but nothing was done.

From the MEMOIRS OF THE LIFE OF COLONEL MACERONI. LATE AlDE-DE'-CAMP to JOACHIM MURAT, King of NAPLES etc.
LONDON, JOHN MACRONE, ST. JAMES' SQUARE, MDCCCXXXVIII

Star and Stripes - Geoglyphs Titicaca


A geoglyph of Titicaca - As seen by Google Maps
Coordinates -15.544474,-70.03443
Note that this structure is superimposed to an older one. Is it an incongruent restoration?


The star viewed from the ground (Courtesy, Gary Mariscal Herrera, Director Instituto Nacional de Cultura, Peru)

Wednesday, January 19, 2011

Manidhara-Nagaraja

Un grande frammento, forse parte dell’alone luminoso di una statua, è esposto al Museo d'Arte Orientale ed è una tipica produzione degli artigiani Newar operanti in Tibet alla metà del secolo XV.  Un vegetale rampicante disegna le volute al cui interno si collocano le figure di un Nagaraja (re dei serpenti e protettore dei tesori contenuti nelle profondità delle acque) e di Manidhara (il Portatore del Gioiello). Manidhara e Nagaraja insieme rimandano al mito di Nagarjuna (Acharya Nāgārjuna,  150-250 AD, filosofo indiano, fondatore di una scuola buddista) che portò agli iuomini il gioiello della Prajñaparamita (La perfezione della saggezza trascedente) ricevuto dal re dei Naga.


Arte tibetana, Museo Arte Orientale, Torino