A fire piston, sometimes called a fire syringe or a slam rod fire starter, is a device of ancient origin which is used to kindle fire. It uses the principle of the heating of a gas (in this case air) by rapid and adiabatic compression to ignite a piece of tinder, which is then used to set light to kindling.
Description and use
A fire piston consists of a hollow cylinder sealed at one end and open at the other. Sizes range in length from 3 to 6 inches (7.5 to 15 cm) with a bore about 0.25 inch (6–7 mm) in diameter, to 10 to 14 inches (25 to 35 cm) with a bore about 0.5 inch (14 mm) in diameter. A piston with an airtight circular seal is fitted into the cylinder. String packing, rubber gaskets, or grease are used to create an air-tight but slippery seal. At the end of the piston is a small cavity, where tinder can be attached without it being crushed during subsequent operations. The piston can be completely withdrawn from the cylinder for installation or removal of the tinder.
The piston (or cylinder) has a handle on the end to allow a firm grip to be applied to it, or a large enough surface area to strike it sharply without causing pain, while the cylinder (or piston) is braced or slammed against a hard surface. The compression of the air when the piston is quickly forced into the cylinder causes the interior temperature to rise sharply to over 400 °F (260 °C), the autoignition temperature of tinder. This is hot enough for the tinder on or in the piston face to ignite with a visible flash that can be seen, if the cylinder is made of translucent or transparent material. The piston is then quickly withdrawn, before the now-burning tinder depletes the available oxygen inside the cylinder. The smouldering tinder can then be removed from the face of the piston and transferred to a larger nest of tinder material. The ember is then fanned or blown upon vigorously to create a flame, at which time various stages of larger kindling can be added until built into a full-scale fire.
Ancient and modern versions of fire pistons have been made from wood, animal horns, antlers, bamboo, or metal. Today, fire pistons are commonly constructed from wood, metal, or plastic. Do-it-yourself designs have become available using wood dowels, PVC and copper pipe, and rubber O-rings, to build versions costing less than US$2 each.
Principle of operation
Rapid compression of a gas increases its pressure and its temperature at the same time. If this compression is done too slowly the heat will dissipate to the surroundings as the gas returns to thermal equilibrium with them. If the compression is done quickly enough, then there is no time for thermal equilibrium to be achieved. The absolute temperature of the gas can suddenly become several times that of its surroundings, increasing from the original room temperature of the gas to a temperature hot enough to set tinder alight. The air in the cylinder acts both as a source of heat and as an oxidizer for the tinder fuel.
The same principle is used in the diesel engine to ignite the fuel in the cylinder, eliminating the need for a spark plug as used in the gasoline engine. The principle of operation is closer to the hot bulb engine, an early antecedent to the diesel, since the fuel (tinder) is compressed with the gas, while in a diesel the fuel is injected when the gas is already compressed and at a high temperature.
Fire pistons have a compression ratio of about 25 to 1. This compares with about 20:1 for a modern diesel engine, and between 7:1 and 11.5:1 for a gasoline engine. The fire piston is made deliberately narrow so that unaided human strength can exert enough force to compress the air in the cylinder to its fullest extent. To achieve a high compression ratio, the final compressed volume of the tinder and air must be small relative to that of the length of the piston tube. These two factors together mean that only a tiny amount of tinder can be lit by a fire piston, but this can be sufficient to light other tinder, and in turn to light a larger fire.
The tinders that ignite at a very low temperature work best. Easily-combustible materials such as char cloth or amadou work well as tinder, and can also hold an ember. By contrast, cotton fibers ignite at 455 °F (235 °C) and will flash brightly but do not hold an ember. The bright flash of light is sometimes sufficient for demonstration purposes, but will not start a persistent fire.
The construction of a hand-operated pump, such as an ordinary bicycle pump, is very similar except that the pump also has valves and a hose to deliver compressed air as an output. In the case of the pump, the heating of the compressed air is an undesired side effect. In both fire piston and pumps, the mechanism and lubricants must be chosen to resist high peak temperatures and pressures.
The fire piston may have been in use in Southeast Asia since the 17th century, but documentation of this is unclear or disputed. The first known documented fire piston in the West was made in 1745 by the Abbot Agostino Ruffo of Verona, Italy, who was making a pair of air guns for the king of Portugal, John V. While Ruffo was testing a gun's air pump for leaks by plugging its outlet with a scrap of wood, he noticed that, after he had pressurized the pump, the wood had been scorched. Subsequently, he found that tinder was ignited by the pump. Ruffo made an apparatus to study the phenomenon further, but his invention was not popularized.
It is recorded that the first fire piston made its wider debut in front of scientists in 1802, and was patented in 1807 simultaneously in both England and France. Fire pistons, or "fire syringes" as they were called then, enjoyed a brief period of popularity in parts of Europe during the early nineteenth century, until being displaced by the friction match invented in 1826.
Fire pistons have been used in Southeast Asia as a means of kindling fire since at least the mid-nineteenth century and perhaps for much longer. Their use has been documented from Burma, Thailand, Laos, the Malay Peninsula, the Philippines, Borneo, Sumatra, Java, some of the islands east of Java including Flores, and possibly Madagascar. Unlike in the West, where fire pistons were made of metal, fire pistons in Southeast Asia were variously constructed of metal, bamboo, wood, ivory, bone, and horn.
The antiquity of the fire piston in Southeast Asia is a matter of debate, including whether it was introduced from Europe or invented independently in Southeast Asia. Balfour summarizes the arguments on both sides, which amount to the following: On the one hand there appear to be no reports of the fire piston in Southeast Asia prior to around 1865. On the other hand, assuming the fire piston came from Europe as an item of trade, it must have been introduced in the window of roughly 1815 to 1830, leaving an improbably short time for it to be adapted to local materials and to spread to peoples as remote as the Kachin of northern Burma and the Igorot of highland Luzon. It is clear that the precursor to the fire piston in Europe was the air gun, and that the heating of rapidly compressed air—to the point where it could ignite tinder—was a chance discovery. What the precursor to the fire piston in Southeast Asia might have been however is unknown. Suggestions range from the piston bellows to the blowgun, the pop gun, and even the mortar and pestle for betel nut, but none is completely satisfactory.
- Manansala, Paul K. (2006-03-24). "Metallurgy, Southeast Asian (Glossary) Piston bellows". Retrieved 2007-05-28.
- "Nuova Osserv(azioni) sopra l'Aria condensata dentro d'una Siringa" [New observation on air condensed inside a syringe] (1745) Giornale de' Letterati, 1 : 307–308. (in Italian)
- Govi, Gilberto (1876) "Sull'invenzione dell'Accendi-fuoco Pneumatico" [On the invention of pneumatic fire lighters], Atti della Accademia Nazionale dei Lincei, 2nd series, 3 (2) : 41–44. (in Italian)
- Govi, Gilberto (1876) "Sur l'invention du briquet pneumatique" (On the invention of the pneumatic lighter), Comptes rendus, 83 : 541–543. (in French)
- (Editorial staff) (September 21, 1876) "Societies and Academies: Paris: Academy of Sciences, Sept. 4," Nature, 14 : 468.
- In 1802, a worker in St. Etienne, France, who had long been making improvements to air rifles, noticed that (1) when the gun was fired in the dark, it emitted a bright light, and (2) if there was lint present in the gun when the gun was pressurized, the lint would become scorched or even ignite. Word of these observations reached Messrs. Eynard, Haèz, and Gensoul, who confirmed them and publicized them. Joseph Mollet (1756–1829), a professor of physics in Lyon, learned of these facts and investigated them. In 1804, he presented his findings to the Academy of Lyon. See:
- Mollet, J., Mémoire sur deux faits nouveaux, l'inflammation des matières combustibles et l'apparition d'une vive lumière obtainue par la seule compression de l'air; lu dans la séance publique de l'Académie de Lyon le 27 mars 1804 [Memoir on two new facts, the ignition of combustible materials and the appearance of a bright light obtained only by the compression of air; read in the public session of the Academy of Lyon on the 27th of March 1804] (Lyon, France: Ballancre père et fils, 1811). In 1804, Mollet suggested that his findings could be used to make a fire piston. From p. 13: "Ce procédé nouveau assure tellement la réussite de l'expérience, que l'appareil qu'on vient de décrire pourrait être considéré comme une espece de briquet." (This new procedure so assures the success of the experiment that the apparatus that was just described could be considered as a type of lighter.) Mollet appended (pp. 30–31) the names of several inventors who had made fire pistons: Mr. Dumotiez (or Dumotier) of Paris; Mr. Dubois, a foundry worker from Lyon; and Mr. Thibaudier, another resident of Lyon.
- Dhombres (1811) "Rapport sur un mémoire de M. Mollet, relatif à la production de la lumière et de chaleur par l'effet de compression" [Report on a memoir by Mr. Mollet, regarding the production of light and heat by the effect of compression], Notice des Travaux de l'Académie du Gard pendant l'année 1811, part 1, pp. 175–182.
- (Pictet) (1803) (Letter from Prof. Pictet to Mr. Tilloch), Philosophical Magazine, 14 : 363–364.
- (Editorial staff) (1803) "Flash from an air-gun," Journal of Natural Philosophy, Chemistry and the Arts, 4 : 280.
- Hart, John (1823) "On light produced by the discharge of an air-gun," The Quarterly Journal of Science, Literature and Art, 15 : 64–66.
- Thénard, Louis Jacques (1830) "Observations sur la lumière qui jaillit de l'air et de l'oxigène par compression" (Observations of the light that springs from air and oxygen as a result of compression), Annales de chimie et de physique, 2nd series, 44 : 181–188.
- In 1806, a "Colonel Grobert", who probably was Jacques François Louis Grobert (1757-181?), a colonel in the French artillery, conceived a fire piston (briquet pneumatique, pneumatic lighter), but he had it fabricated by a professional maker of scientific instruments in Paris, "Dumotier" (variously spelled Dumoutier, Du Moutier, and Dumotiez). See:
- Grobert (April 1806) "Moyen de produire des inflammations par l'air comprimé" (Means of producing ignitions by compressed air), L'Esprit des journaux, françois et étranger, 4 : 139–145.
- Morelot, Simon, Histoire naturelle appliquée à la Chimie [Natural history applied to chemistry] (Paris, France: F. Schoell and H. Nicolle, 1809), vol. 1, p. 94. From page 94, footnote 1: " (1) Inventé par le colonel Grobert, exécuté par M. Dumotier. " ((1) Invented by Colonel Grobert, executed by Mr. Dumotier.)
- Krehl, Peter O. K., History of Shock Waves, Explosions, and Impacts (Berlin, Germany: Springer Verlag, 2009), p. 273.
- (Staff) (1807) "Specification of the Patent granted to Richard Lorentz, … for certain inventions (communicated to him by Foreigners residing abroad) of different Machines or Instruments, one of which will produce instantaneous Light, and the other instantaneous Fire. Dated February 5, 1807." The Repertory of Arts, Manufactures, and Agriculture, 2nd series, 11 : 250–253.
- Fox, Robert. 1969. The fire piston and its origins in Europe. Technology and Culture 10:355–370.
- Diesel Story (Film). Prelinger Archives: Shell Oil. 1952. Retrieved 2007-02-16.
- Gurstelle, William (2009). "Rudolf Diesel and the Fire Piston". Make. Sebastopol, California: O'Reilly Media. 19: 166–168. ISSN 1556-2336.
- Smiley, Edwin (February 1915) "Primitive methods of making fire," Boys' Life, 4 (12) : 9.
- Post, Augustus (September 1929) "The Landing Field: The Diesel engine," Boys' Life, 19 (9) : 44.
- Spencer, Billie (March 1974) "Man and fire," Boys' Life, 64 (3) : 6.
- Hough, Walter. 1928. Fire-making apparatus in the United States National Museum. Proceedings of the United States National Museum 73(2735):1–72.
- Balfour, Henry. 1908. The fire piston. Annual report of the Board of Regents of the Smithsonian Institution, showing the operations, expenditures and condition of the institution for the year ending June 30, 1907, 565–593. Washington, DC: Government Printing Office.
- OGATA, Masanori; Yorikazu SHIMOTSUMA (October 20–21, 2002). "Origin of Diesel Engine is in Fire Piston of Mountainous People Lived in Southeast Asia". First International Conference on Business and technology Transfer. Japan Society of Mechanical Engineers. Retrieved 2007-05-28.
- "The Pneumatic Tinder-box" (PDF). New York Times. 9 October 1876. Retrieved 19 August 2009.
- Arbor Scientific, Tools That Teach, Fire Syringe P1-2020; http://www.arborsci.com/Data_Sheets/P1-2020_DS.pdf
- Balfour, Henry (1907) "The fire piston," Annual Report of the Board of Regents of the Smithsonian Institution, pp. 565–598.
- Fox, Robert (July 1969) "The Fire Piston and Its Origins in Europe", Technology and Culture, 10 (3) : 355–370.
- Jamison, The Remarkable Firepiston Woodsmoke (1994) Menasha Ridge Press, Birmingham AL ISBN 0-89732-151-0
- Jamison, Richard with Mel Deweese, "The remarkable fire piston" in: Richard and Linda Jamison, Primitive Skills and Crafts: An outdoorsman's guide to shelters, tools, weapons, tracking, survival, and more (New York, New York: Skyhorse Publishing, 2007), pp. 163–176.
- Rowlands, John J. The Cache Lake Country (1947) ; W. W. Norton and Company, Inc., New York, NY
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