From the middle of the 19th century to the beginning of the 20th century, large pneumatic post systems, some hundreds of kilometers long, were built in some large cities on different continents. There were also smaller systems that automatically transported smaller objects within a building or between several neighboring buildings by means of pneumatic tubes. In contrast to telescopic post systems, these systems are still in use.
From a postal perspective, the first pneumatic tube was set up in London in 1853 . It served in the telegraph office as a pneumatic tube mail. The pneumatic tube in Vienna went into operation on March 19, 1875, the pneumatic tube in Berlin on December 1, 1876.
Basics of pneumatic tube technology
The practical basics of pneumatic post have been known since the blowpipe was invented in various cultures . The theoretical and experimental basis of the pneumatic tube system was developed in the Pneumatika of Heron of Alexandria (1st century BC). Here, in Chapters 56 and 57, the principles of creating negative and positive atmospheric pressure in a cylinder into which a piston is inserted have been described. However, Heron was not yet concerned with the transport of objects that should have been transported in a tube due to the pressure difference.
Pioneer of modern pneumatic post
Around 1810, the English engineer George Medhurst (1759–1827) made serious efforts for the first time to use atmospheric air for industrial and transport purposes. In corresponding publications he suggested pumping the air out of an iron tube in order to achieve a corresponding driving force through the pressure difference achieved; Medhurst is therefore considered to be the inventor of the pneumatic tube post.
The English engineer Vallance took up this idea in 1818 with the idea of transporting people and goods from London to Brighton in a tunnel-like, cast-iron and correspondingly large tube. These efforts were unsuccessful, but attempts to transport mail by means of air pressure in small-caliber tubes brought initial success. The inventor of the ship's propeller , Josef Ressel , also dealt with the pneumatic tube. He developed it further in 1827 and brought it to maturity in 1847.
In 1852, the French Abbé Moigno set up a test route to transport mail using compressed air, which ultimately led to the French Galy Cazalar and the English Josiah Latimer Clark independently filing corresponding national patents in 1854. They described a technical device with which small parcels and letters enclosed in tin cans could be transported through pipes to a not very distant place with high air dilution or compression.
With the help of an electrically driven compressor , the necessary suction or pressure (or combined at entry and exit points at the same time) is generated in order to convey the cylindrical containers (cans) in which the goods are to be shipped through laid pipes. The diameter of the bushings is only slightly smaller than the inner diameter of the unitary tubes. These rifles are inserted at entry and exit points and, in the case of multi-point systems, the destination is determined with an input in the control. In order to reach every starting point, electronically controlled switches are built in, which allow up to four distributions. In the case of medium-sized and large systems, it is controlled by a computer. In order to protect the sensitive transport goods, the bushes are braked pneumatically in front of each station. The smallest pneumatic tube system is the 2-point system. It only works back and forth. A larger version is e.g. B. the cash disposal . The money is sent from the cash register of a supermarket or bank counter directly to the safe or a security area. Such a single-line system can have up to 99 input and output points with individual assignment of each individual station. The largest pneumatic tube system is the multi-line system. Such a system has up to 512 stations and up to 64 lines. The sleeves can, depending on the design and application, z. B. long straight individual routes, with up to 11 meters per second (around 40 km / h) through the tube system. Normal speeds are in the range of six to eight meters per second, with sensitive broadcasts only two to three meters per second. Depending on the system, several cans can be transported at the same time (train).
The differential pressure acting on the bushing multiplied by its cross-sectional area must be sufficient to sufficiently exceed its weight during upward transport plus friction forces. Bushings typically have 2 sealing rings protruding sufficiently on the outside at a distance of 3 to 5 pipe diameters in order to achieve smooth curves with a radius of 5 to 10 pipe diameters. Front and rear dome-like closures of the transparent sleeve made of lightweight plastic, which are often closed with a bayonet catch, serve to bump into the buffered end stations.
Bushes must be waisted in the middle in order to overcome curves. They should always rest on the wall with the sealing strips typically made of textile fleece.
Earlier telescopic post systems were mainly used for the fast delivery of letters and telegrams between important post offices within a city (such as the pneumatic tube in Hamburg , the pneumatic tube in Berlin or the pneumatic tube in Munich, but also the pneumatic tube networks in America and many in other countries, see below). Smaller 2-point systems can often be found in smaller medical practices with a laboratory. The cost of such a system is around 3200 euros (as of January 2010) .
Urban pneumatic tube networks
The first pneumatic tube was built in London in 1853 by Josiah Latimer Clark . It was a 220 yard link between the London Stock Exchange and the Central Telegraph Office. Similar connections between a telegraph office and the stock exchange were established in Berlin in 1865 and in Paris in 1866.
These first systems were only suitable for transporting small objects. B. the London facility is 1.5 inches (3.81 cm) in diameter . Clark later founded the Pneumatic Despatch Company together with TW Rammell , which built a 30 inch (76.2 cm) tube in 1861 in which loads of up to 3 tons could be transported. This Pneumatic Dispatch Railway was in operation until 1874. There were similar systems in New York: A 107- foot (32.6 m) long and 6-foot (1.83 m) diameter system by Alfred Ely Beach built in 1867 that could transport twelve people. An even larger facility, 312 feet (95 m) long and 9 feet (2.74 m) in diameter, was built in the rock below Broadway in 1869/1870 . In its first year, the Beach Pneumatic Transit carried over 400,000 passengers; it went out of service in 1873. These systems could not prevail in passenger transport against the underground , in which steam locomotives were first used with success and electric locomotives as early as 1890.
Pneumatic tube networks in Europe
The following pneumatic tube networks existed in Europe:
- England and Scotland: Birmingham, Glasgow, Liverpool, London, Manchester, Newcastle
- France: Paris (1866 (1879 public) - 1984) and Marseille (1910–1964)
- KuK monarchy and successor states: Prague (from 1887), Vienna and - only a few hundred meters long - in Karlovy Váry / Karlsbad. There was probably also a pneumatic post in Trieste at the time of the Austro-Hungarian monarchy. On the Italian-language telegram forms of the KuK postal administration for Trieste there is a preprinted reference to the transport of telegrams by posta pneumatica .
- Ireland: Dublin
- Italy: Florence (possibly), Genoa (since the 1850s approx. 12 km), Milan, Naples, Rome and probably also Trieste (see above)
- Rome / Vatican City: a pneumatic tube connection to the Roman pneumatic tube network (stamps with the inscription Città del Vaticano / posta pneumatica are occupied)
- Czech Republic: Prague , out of service since the 2002 floods
In Hamburg from 1962 to 1976 there was a globally unique large pneumatic post of the Deutsche Bundespost with an inner diameter of 45 cm for the two driving tubes. These ran between the main post office 3 (Hühnerposten, near the train station) and the post office 11 in the city center (Alter Wall) on two largely different routes, each around 1.8 km in length. 2000 normal letters fit into a “can” (transport container) . The test facility was dismantled, some pipes remained underground. Guided tours lead to relics.
In Austria there was a pneumatic tube network in Vienna from 1875 to 1956 . In Graz there was an underground pneumatic tube connection between the telegraph office (built in 1927/1931), where telegrams were formerly recorded as text on strips of paper and sent to the telegram delivery in the building of what was then the main post office 8010, Neutorgasse on the next block. When the post office moved to the building around 2000, the pneumatic post station was dismantled.
Photographs by C. August Schmidt & Söhne (Hamburg) suggest that they manufactured a pneumatic tube system for Amsterdam that was ready for dispatch in the 1930s. It is not known whether this was delivered and installed. According to a letter of recommendation from Mix & Genest , Rotterdam had a city tube post system with two stations and 1,400 m of transport pipe.
Non-European pneumatic tube networks
- see also pneumatic tube networks in America
Outside of Europe, the largest pneumatic tube system that could also transport parcels existed in New York City . There were also corresponding plants in Boston , Chicago , Philadelphia and St. Louis . There were also pneumatic tube systems in Buenos Aires (Argentina) as the expreso urbano (city express service ) of the telegraph office as well as in Rio de Janeiro and São Paulo (both Brazil). In Brazil, as in Argentina, the pneumatic postal stationery was published by the telegraph administration, which indicates the original purpose of the pneumatic tube network to speed up the transmission of telegrams in large cities.
Algiers (Algeria / Africa)
There was also a pneumatic tube system in Algiers (Algeria), which was still in operation until shortly after the end of French colonial rule (operating period from April 4, 1910 to July 5, 1962) and, as far as it has become known, partly as exprès urbain (city express traffic ) was also supplied with other transport options. In Algiers , pneumatic postal stationery from the French postal service was initially used. In 1938 a pneumatic postal stationery was published for Algiers, which was intended for use in the exprès urbain .
The survival of the pneumatic tube
Even after the pneumatic post for public postal traffic was discontinued, the network was still used internally, for example for the transport of incoming express mail to the delivery post office.
In the pneumatic tube districts of the pneumatic tube post in Berlin and the pneumatic tube post in the affiliated post offices, day or special stamps with hour and minute information, usually at 10-minute intervals, were used (see above).
The purpose of stamping the pneumatic tube is to document to the minute at what time the shipment was accepted and forwarded according to the schedule. This was awkward with the early dies that the moveable elements were plugged into. As soon as punches with rotatable elements were used, this process could be accelerated so that the time group could be changed first every 15 minutes, then every 10 minutes and finally every 5 minutes. The minute-by-minute documentation of the handling of the shipment became possible when the time clock was introduced. Here a clock mechanism drove the time group of the stamp, whereby a precise time setting of the stamp was guaranteed without further human intervention.
Stamps with a 5-minute setting are known from Paris, while only the usual day stamps were used in Marseille . Pneumatic post deliveries in Marseille can only be recognized by the corresponding postage, the usual note "pneumatique" and the arrival stamp of the delivery post office on the front or back, usually from the same day.
Postage stamps issued specifically for pneumatic post were only available in Italy. In the Italian catalogs, they are usually recorded after the express courier stamps under the special heading posta pneumatica . In France, a value stamp (an imprinted postage stamp) of the Chaplain type was used, which was used exclusively on postal items (envelopes, card letters or postcards with imprinted stamps) and also on telephone tickets for over a hundred years. It is noteworthy that this stamp bears the inscription TÉLÉGRAPHE in all denominations , which means that the Parisian pneumatic tube system was initially actually set up for the transport of telegrams and, before it was merged with the postal system, not the post office, but that for telegraphy responsible Ministry of the Treasury. (The value stamp of the Chaplain type with the inscription TÉLÉGRAPHE was initially also used for French telephone billets , until the inscription was replaced by the word TÉLÉPHONE .) Brazilian pneumatic postal stationery also have a value stamp specially created for them.
In contrast to the long-lasting value stamp of the Chaplain type in France, a value stamp was developed in Germany at the beginning of the inflationary period that was used exclusively for pneumatic mail whole and was only in use for two years. It is available in the denominations of 200 pfennigs and 80 marks for pneumatic post cards and 225 pfennigs and 100 marks for pneumatic tube envelopes.
In Argentina, Brazil, Germany, France, Austria and Czechoslovakia special postal stationery was published for the pneumatic tube, which as used items represent an excellent documentation of the postal pneumatic tube system.
The modern pneumatic tube
Nowadays, pneumatic tube systems are mainly used inside buildings, for example in trade for the transport of money or books, in hospitals for the internal dispatch of blood samples, medical files, findings and forms. In the Charité in Berlin , around 3500 patient samples, X-rays or analysis materials are transported gently and quickly between the wards and the laboratories every day. One of the most modern and youngest systems of this type was installed in the Heidelberg University Hospital . There, an approximately 25 km long tube system with more than 100 lines connects 152 stations via various branches. Using transponder technology , around 3800 samples find their way from the stations to the laboratory every day.
The Saarland University Hospital in Homburg has one of the most modern and largest systems in the world with over 70 lines and approx. 200 stations. The now 35-year-old pneumatic tube system at the Hannover Medical School is currently being completely modernized. It is over 60 km long and has over 600 stations. The special thing about this system is that all connections only work with negative pressure and not with positive pressure. Each station has a transmitting and a receiving tube, which means that a significantly larger transport volume is possible. In the medical school, over 3000 cans are currently dispatched in the course of a day. The merging of clinics makes pneumatic tube systems more interesting, as the connection of new extension buildings entails longer distances within the clinic.
The modernization also aims to transport not only samples, but also blood products. Weight, transport time, hemolysis and centrifugal and acceleration forces play a role here.
Tissue samples from ongoing operations are particularly time-critical; they can be given priority over less urgent consignments in the pneumatic tube system.
Pneumatic tube systems in department stores are used to connect the individual cash registers with the main cash register in order to deliver cash or change money. The increasing acceptance of cashless payment by debit card and credit card mean that the security against robberies gained by pneumatic tube systems is becoming less important.
Other users of modern pneumatic tube systems can be found in the chemical industry, in steelworks, in paper mills and in the automotive industry. In 1998 , for example, the French car manufacturer Peugeot had a pneumatic tube system installed in the Sochaux plant to supply the production lines with the right lock sets for door and trunk locks.
Modern systems for "communication and transport automation", as such systems are called by the manufacturers, are able to transport documents, goods or workpieces weighing up to 28 kg with a length of 50 cm and a diameter of up to 30 cm. Tube systems with over 100 lines and over 1000 stations can be implemented here.
In the Erfurt Clinic , which was completed in 2000 , a hospital pneumatic tube system with 35 sending and receiving stations was built and expanded to 69 stations by 2011. It has operational monitoring displayed on the screen, documents each individual dispatch (typically 1500 per day) and can be remotely controlled and maintained. Shipments can be rerouted, an incoming shipment can be reported by email. A study by the clinic evaluated that blood samples arrive unadulterated through sufficiently gentle transport - braking the sleeves on an air cushion. At the switches and end stations, locks and air ducts are used to ensure that the transport air does not move any germs through the hospital.
The Federal Chancellery in Berlin, which was completed in 2001 , also has a pneumatic tube system with which up to 2,400 transactions are sent per month (April 2019).
In June 2016 the Kaiser-Franz-Josef-Spital in Vienna received a modern pneumatic tube system that gently sends blood samples to the analysis laboratory. The waiting times for the diagnosis could thus be reduced to less than an hour.
Both the throwing in of standardized cans (typically rounded cylindrical, made of sheet metal) with the daily turnover of business people in the receiving equipment of the night safe of the house bank and - especially at gas stations - from the cash register in a room on the floor or in the neighboring room are used to secure cash from nighttime unauthorized access. In contrast to pneumatic post, the shipment only runs in one direction and - at least initially - purely gravity-driven.
There are only five major pneumatic tube system manufacturers in the world; The German company Aerocom from Schwäbisch Gmünd claims to be the world's largest provider (as of 2015).
In Austria there are two manufacturers of pneumatic tube systems; They deliver worldwide: Thalmayr GmbH. based in Lamprechtshausen and Sumetzberger GmbH from Vienna , which has been dealing with pneumatic post since 1964 and has equipped 170 hospitals in China and the Kaiser-Franz-Josef-Spital in Vienna with pneumatic post systems in 2016 .
The pneumatic tube in culture
Representation in the film
In the film Brazil , a pneumatic tube system is part of the gigantic bureaucracy of the Ministry of Information . The hero succeeds in sabotaging the system by overloading the line and thus leading the entire agency into chaos.
In the movie Shadow and the Curse of Khan , the hero uses a huge pneumatic tube network that stretches across New York to get information from his agents.
In François Truffaut's Stolen Kisses , a message from Antoine Doinel in the pneumatic tube system in Paris is followed with several settings of the underground system on her way to Fabienne Tabard.
In part twelve of the Olsen Gang films, the three crooks send a load of hot coffee through the pneumatic tube, which the recipient promptly tips over his trousers when the capsule is opened.
In the children's series Hallo Spencer , Spencer, the main character, has a pneumatic tube system.
In the animated series Futurama , the pneumatic tube is often used in the bureaucracy and as "local public transport" for people.
In the television series Lost , a pneumatic tube system is also used, but the shipments are conveyed to a meadow and do not reach their supposed destination.
In the computer animation film Everything is upside down , the memories are assigned to an emotion and, at the end of the day, conveyed to the long-term memory via a pneumatic tube.
In John Wick: Chapter 2 , pneumatic tube is used for internal communication in the Continental hotel.
Representation in literature and art
In Theodor Fontane's wife Jenny Treibel , messages of particular importance between the Schmidt and Treibel families use the Berlin pneumatic tube system . "Between nine and ten, two pneumatic tube letters had arrived at Schmidt's, a case that, in this duplication, had never been seen before."
Franz Kafka (1883-1924) often communicated by pneumatic tube - not only from his place of work to meet Max Brod, for example, but also with his girlfriend Milena Jesenská, to whom he sent love letters by pneumatic tube. In Kafka's work, especially the correspondence and the diaries, there are therefore many references to pneumatic tube communication.
Even in Kurt Tucholsky's short stories to descriptions of Berlin and Paris pneumatic tube culture find.
- Double pneumatic tube (mail that was sent via pneumatic tube at the point of origin and destination)
- post Office
- Pipeline transportation
- Edmund Heusinger von Waldegg: Handbook for special railway technology. Volume 1 (3): Railway construction. Leipzig 1877, pp. 938–951 and table LIX-LX. Reprint of the original edition from 1877: Archiv-Verlag, Braunschweig 2005.
- Heron of Alexandria: Pneumatica digital edition in English translation with numerous illustrations
- Heinze, Sven: Pneumatic Post Systems , Goslar 1956.
Handheld electrical telecommunications dictionary
- 1st edition:
- Volume 1 A – K: Telescopic post, internal pneumatic post
- Volume 2 L – Z: Pneumatic Post; Pneumatic tube blower; Pneumatic tube collection point; Pneumatic tube distribution point; Pp. 305-307; Zettelrohrpost (pneumatic tube in long-distance offices); P. 866 f.
- 2nd Edition
- Volume 3 Q – Z: Pneumatic direct systems; Pneumatic tube systems; Pneumatic tube switch systems; Pp. 1419-1422; Slip tube mail; Slip tube mail with automatic control; Pp. 1956-1959
- 1st edition:
Handheld dictionary of postal services
- 1st edition; Pp. 553-559
- 2nd, completely revised edition, Frankfurt am Main, 1953, Federal Ministry for the Post and Telecommunications (Ed.); Pp. 626-636
- NN: The development and the current state of urban pneumatic tube technology . Berlin 1929.
Pneumatic post Buenos Aires
- C. August Schmidt & Sons: 100 years of C. Aug. Schmidt & Sons , Hamburg 1941, p. 28.
Pneumatic tube London
- Beach, Alfred Ely: The pneumatic dispatch, with illustrations: a compilation of notices and information concerning the pneumatic system of transportation as new building and operating in England; together with accounts of its first trial in the United States, and of proposed applications of the system to passenger and postal service ... , New York 1868
- Pneumatic tube. With high pressure in the underground from Einestages , Spiegel Online
- The Museum of RetroTechnology: Pneumatic Networks. English-language site with many historical pictures of the pneumatic tube technology.
- Pneumatic mail & Pneumatic mail in the Dead Media Project (English)
- Berlin Underworlds History of the Berlin pneumatic tube
- Buispost.eu How does pneumatic tube work (with many (old) pictures of the pneumatic tube technology)
- Aerocom GmbH & Co, quick rifle from Schwäbisch Gmünd in the Stuttgart newspaper
- Tracking shot in a modern pneumatic tube system of the Norwegian Parliament on YouTube (Norwegian, trip starts at 1:00 am)
- A hike in the footsteps of the Hamburger Unterwelten e. V., 2015. Retrieved August 28, 2019.
- Sumetzberger Krankenhausrohrpost - German Ing.Sumetzberger GmbH, youtube.com, April 19, 2011, accessed April 23, 2020. Video (8:22)
- Eavesdropping and hacking impossible: Digital Minister swears by pneumatic tube system , n-tv , April 20, 2019, accessed on April 20, 2019.
- KFJ-Spital relies on historic pneumatic post , orf.at, August 5, 2016, accessed on August 5, 2016.
- "Send a bomb over there": The pneumatic tube has not had its day . In: FAZ.NET . ISSN 0174-4909 ( faz.net [accessed July 28, 2018]).
- Pascal Morche: Sssst and plopp. The pneumatic tube - an almost forgotten form of communication. In: spiegel.de , Der Spiegel , March 1, 1999.
- Steirische Landesausstellung, "Verkehr", Knittelfeld, 1999 In: Bisdato, accessed March 21, 2013
- Serge Spitzer, Round the Corner In: e-flux, March 7, 2006.