Architonnerre
Encyclopedia
The Architonnerre was a steam-powered cannon
, a description of which is found in the papers of Leonardo da Vinci
dating to the late 15th century, although he attributes its invention to Archimedes
in the 3rd century BC.
Leonardo's description was hidden amongst his papers until it was rediscovered by Étienne-Jean Delécluze
of the French Institute in 1838 and published in the magazine L'Artiste
in 1841, well after the modern high pressure steam engine
had been independently invented.
A conventional muzzle loading cannon
had a strong metal tube connecting the vented end, where the fuse would normally be placed, to a copper boiler
, terminating below the water level inside but describing an inverted U above it in the manner of a syphon. A fire of charcoal heated the vented end of the cannon and the boiler so that the metal of the cannon's end became red hot and the boiler was boiling vigorously. Steam was allowed to escape from the boiler through an opening with a screwed thread so there was no build up of pressure. To fire the cannon a cap was screwed tightly into the boiler opening, triggering an immediate build up of steam pressure in the boiler. This forced the boiling water along the syphon tube into the cannon's base. Here it met the red hot cannon walls and flashed into steam , the pressure of the sudden release of steam forced the cannon ball out of the muzzle.
The weight of the cannon ball is described as one talent. A Roman talent was 32.3 kilograms, although the amount varied across the ancient world by a few kilos.
Steam cannon
A steam cannon is a cannon that launches a projectile using only heat and water. The first steam cannon was designed by Archimedes during the Siege of Syracuse. Leonardo da Vinci was also known to have designed one ....
, a description of which is found in the papers of Leonardo da Vinci
Leonardo da Vinci
Leonardo di ser Piero da Vinci was an Italian Renaissance polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist and writer whose genius, perhaps more than that of any other figure, epitomized the Renaissance...
dating to the late 15th century, although he attributes its invention to Archimedes
Archimedes
Archimedes of Syracuse was a Greek mathematician, physicist, engineer, inventor, and astronomer. Although few details of his life are known, he is regarded as one of the leading scientists in classical antiquity. Among his advances in physics are the foundations of hydrostatics, statics and an...
in the 3rd century BC.
Leonardo's description was hidden amongst his papers until it was rediscovered by Étienne-Jean Delécluze
Étienne-Jean Delécluze
Etienne-Jean Delécluze was a French painter and critic.From 1797 on, he was a pupil of Jacques-Louis David, as he describes in his biography of David...
of the French Institute in 1838 and published in the magazine L'Artiste
L'Artiste
L’Artiste was a weekly illustrated review published in Paris from 1831 to 1904, supplying "the richest single source of contemporary commentary on artists, exhibitions and trends from the Romantic era to the end of the nineteenth century."...
in 1841, well after the modern high pressure steam engine
Steam engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be...
had been independently invented.
Description of operation
The following is the most likely means of operation from the description given.A conventional muzzle loading cannon
Cannon
A cannon is any piece of artillery that uses gunpowder or other usually explosive-based propellents to launch a projectile. Cannon vary in caliber, range, mobility, rate of fire, angle of fire, and firepower; different forms of cannon combine and balance these attributes in varying degrees,...
had a strong metal tube connecting the vented end, where the fuse would normally be placed, to a copper boiler
Boiler
A boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluid exits the boiler for use in various processes or heating applications.-Materials:...
, terminating below the water level inside but describing an inverted U above it in the manner of a syphon. A fire of charcoal heated the vented end of the cannon and the boiler so that the metal of the cannon's end became red hot and the boiler was boiling vigorously. Steam was allowed to escape from the boiler through an opening with a screwed thread so there was no build up of pressure. To fire the cannon a cap was screwed tightly into the boiler opening, triggering an immediate build up of steam pressure in the boiler. This forced the boiling water along the syphon tube into the cannon's base. Here it met the red hot cannon walls and flashed into steam , the pressure of the sudden release of steam forced the cannon ball out of the muzzle.
Leonardo's own description
Account from the Nelson Examiner and New Zealand Chronicle, 1842:The Steam-Engine. — M. Delecluze has lately made a discovery among the manuscripts of Leonardo da Vinci, carrying back a knowledge of the steam-engine to at least as far back as the 15th century. He has published in the Artiste a notice on the life of Leonardo da Vinci, to which he adds a fac-simile of a page from one of his manuscripts, and on which are five sketches with the pen, representing the details of the apparatus of a steam-gun, with an explanatory note upon what he designates under the name of the " Architonnerre," and of which note the following is a translation : — " Invention of Archimedes. — The Architonnerre is a machine of fine copper, which throws balls with a loud report and great force. It is used in the following manner : — One third of this instrument contains a large quantity of charcoal fire. When the water is well heated, a screw at the top of the vessel which contains the water must be made quite tight. On closing the screw above, all the water will escape below, will descend into the heated portion of the instrument, and be immediately converted into a vapour so abundant and powerful, that it is wonderful to see its fury and hear the noise it produces. This machine will carry a ball of a talent in, weight." It is worthy of remark that Leonardo da Vinci- far from claiming the merit of this invention for himself or the men of his time- attributes it to Archimedes.
The weight of the cannon ball is described as one talent. A Roman talent was 32.3 kilograms, although the amount varied across the ancient world by a few kilos.