Letterpress printing is a technique of relief printing using a printing press, a process by which many copies are produced by repeated direct impression of an inked, raised surface against sheets or a continuous roll of paper. A worker composes and locks movable type into the "bed" or "chase" of a press, inks it, presses paper against it to transfer the ink from the type which creates an impression on the paper. In practice, letterpress includes other forms of relief printing with printing presses, such as wood engravings, photo-etched zinc "cuts", linoleum blocks, which can be used alongside metal type, or wood type, in a single operation, as well as stereotypes and electrotypes of type and blocks. With certain letterpress units it is possible to join movable type with slugs cast using hot metal typesetting. In theory, anything, "type high" or.918 inches can be printed using letterpress. Letterpress printing was the normal form of printing text from its invention by Johannes Gutenberg in the mid-15th century until the 19th century and remained in wide use for books and other uses until the second half of the 20th century.
Letterpress printing remained the primary means of printing and distributing information until the 20th century, when offset printing was developed, which supplanted its role in printing books and newspapers. All forms of data collection were affected by the invention of letterpress printing, as were many careers such as teachers, preachers and surgeons and artist-engineers. More letterpress printing has seen a revival in an artisanal form. Johannes Gutenberg is credited with the development in the western hemisphere, in about 1440, of modern movable type printing from individually cast, reusable letters set together in a form. Movable type was first invented in China using ceramic type in 1040 AD. Gutenberg invented a wooden printing press, based on the extant wine press, where the type surface was inked with leather-covered ink balls and paper laid on top by hand slid under a padded surface and pressure applied from above by a large threaded screw, it was Gutenberg's "screw press" or hand press, used to print 180 copies of the Bible.
At 1,282 pages, it took him and his staff of 20 3 years to complete. 48 copies remain intact today. This form of presswork replaced the hand-copied manuscripts of scribes and illuminators as the most prevalent form of printing. Printers' workshops unknown in Europe before the mid-15th century, were found in every important metropolis by 1500. Metal presses used a knuckle and lever arrangement instead of the screw, but the principle was the same. Ink rollers made of composition paved the way for further automation. With the advent of industrial mechanisation, inking was carried out by rollers that passed over the face of the type moved out of the way onto an ink plate to pick up a fresh film of ink for the next sheet. Meanwhile, a sheet of paper slid against a hinged platen, which rapidly pressed onto the type and swung back again as the sheet was removed and the next sheet inserted; as the fresh sheet of paper replaced the printed paper, the now freshly inked rollers ran over the type again. Automated 20th-century presses, such as the Kluge and "Original" Heidelberg Platen, incorporated pneumatic sheet feed and delivery.
Rotary presses were used for high-speed work. In the oscillating press, the form slid under a drum around which each sheet of paper got wrapped for the impression, sliding back under the inking rollers while the paper was removed and a new sheet inserted. In a newspaper press, a papier-mâché mixture called a flong used to make a mould of the entire form of type dried and bent, a curved metal stereotype plate cast against it; the plates were clipped to a rotating drum and could print against a continuous reel of paper at the enormously high speeds required for overnight newspaper production. This invention helped aid the high demand for knowledge during this time period. Letterpress printing was introduced in Canada in 1752 in Halifax, Nova Scotia by John Bushell in the newspaper format; this paper became Canada's first newspaper. Bushell apprenticed under Bartholomew Green in Boston. Green moved to Halifax in 1751 in hopes of starting a newspaper. Two weeks and a day after the press he was going to use for this new project arrived in Halifax, Green died.
Upon receiving word about what happened, Bushell moved to Halifax and continued what Green had started. The Halifax Gazette was first published on March 23, 1752, making Bushell the first letterpress printer in Halifax, Canada. There is only one known surviving copy, found in the Massachusetts Historical Society. One of the first forms of letterpress printing in the United States was Publick Occurrences Both Forreign and Domestick started by Benjamin Harris; this was the first form of a newspaper with multiple pages in the Americas. The first publication of Publick Occurrences Both Forreign and Domestick was September 25, 1690. Letterpress started to become out-of-date in the 1970s because of the rise of computers and new self-publishing print and publish methods. Many printing establishments went out of business from the 1980s to 1990s and sold their equipment after computers replaced letterpress's abilities more efficiently; these commercial print shops discarded presses, making them affordable and available to artisans throughout the country.
Popular presses are, in particular, Vandercook cylinder proof presses and Chandler & Price platen presses. In the UK there is particular affection for the Arab press, built by Josiah Wade in Halifax. Letterpress
Berliner, or "midi", is a newspaper format with pages measuring about 315 by 470 millimetres. The Berliner format is taller and marginally wider than the tabloid/compact format; the Berliner format is an alternative to the broadsheet format. The name refers to the city of Berlin, was contrasted with "North German" and "French" sizes in the early 20th century; the Berliner format is used by many European newspapers, including dailies such as Le Monde in France, Oslobođenje in Bosnia, Le Temps in Switzerland, La Repubblica and La Stampa in Italy, De Morgen, Le Soir and Het Laatste Nieuws in Belgium, Mladá fronta Dnes and Lidové noviny in the Czech Republic, others such as Expresso in Portugal and Jurnalul Național or Evenimentul Zilei in Romania. The French business newspaper Les Échos changed to this format in September 2003, the largest daily papers in Croatia and Montenegro, are in this format. A recent European newspaper to join this trend is Het Financieele Dagblad, the daily Dutch newspaper, focused on business and financial matters on 26 March 2013.
Student publication The University Observer became Ireland's first Berliner-sized paper in September 2009. The Independent in London could not afford to buy new presses. Although the daily Berliner Zeitung is called Berliner, it is not printed in Berliner format. In fact, only two German national dailies use Berliner format: Die Tageszeitung; the majority of the national quality dailies use the larger broadsheet format known as "nordisch", measuring 570 mm × 400 mm. The daily Journal & Courier in Lafayette, Indiana was the first newspaper in North America to be produced in this format, making its debut on 31 July 2006; the Bucks County Herald in Lahaska, followed in 2009, The Chronicle in Laurel, Mississippi, in April 2012, commencing publication at that time. Major papers such as the Chicago Tribune and The Cincinnati Enquirer have tested the format. Since a number of broadsheet newspapers throughout the United States and Canada have adopted a page format similar to Berliner, though some may use a taller page.
In some instances, only the width has changed from the typical broadsheet page, the height has remained the same or close to it. For example, The New York Times used a 22-inch tall by 13.5-inch wide page, but in 2007 downsized to 22 by 12 in. It still refers to itself as a broadsheet though its size is closer to Berliner; the Indian business daily Mint, a collaboration with the Indian media house Hindustan Times Media Limited and The Wall Street Journal, was among the first newspapers to use the Berliner format, starting from 1 February 2007. In Nepal, the Nepali Times became the first and the only newspaper using this format. In Pakistan, the English daily Pakistan Today is published in the Berliner format; the Israeli newspaper Haaretz has been published in this format since 18 February 2007. Though rarely used in Metro Manila, the Berliner is the most popular format in the Philippines. In the Ilocandia, some of the well-known names are the Zigzag Weekly, the Northern Dispatch—commonly called as Nordis—and the Northern Philippine Times.
In the Visayas, the Panay News uses this format. Though not published for commercial purposes, the official publication of the Caritas Manila uses a narrower Berliner format. In March 2009, South Korea's JoongAng Ilbo adopted the Berliner format, becoming the first Korean newspaper to do so. In the same month, Turkey's Gazete Habertürk and Zaman adopted a variation of this format as 350 by 500 mm and become two of the first Turkish newspaper to do so; the format is called Ciner format in Turkey. On 1 June 2012, the UAE's leading English language newspaper, Gulf News, adopted the Berliner format, the first in the Middle East; some South American papers have dubbed the "compact" size as "Berliner". The former size is closer to tabloid; the Buenos Aires Herald, a daily Argentine newspaper founded in 1876, uses the Berliner format, used by La Nueva, a newspaper of the Buenos Aires province. Córdoba newspaper La Voz switched to Berliner from broadsheet in 2016; the Los Tiempos newspaper from Cochabamba releases its editions in Berliner with full color in all pages starting October 2017.
The newspaper was published in broadsheet. Jornal do Brasil, a daily Brazilian newspaper founded in 1891, was published in Berliner from 16 April 2006 until 31 August 2010, when the newspaper ceased to publish its physical issue and transferred all activities to the internet. Only the newsstand edition was in that format, but its success made the format switch extend to the subscriber's edition, which until remained in broadsheet format. In 2008, Salvador-based Correio* switched to Berliner from broadsheet. After being sold by Organizações Globo to J. Hawilla's Grupo Traffic, Diário de S. Paulo, a broadsheet, switched to Berliner, bringing it in line with its sister publications under Rede Bom Dia. In 2003, national newspaper La Tercera switched from tabloid to Berliner. Local papers around Chile have adopte
Johannes Gensfleisch zur Laden zum Gutenberg was a German blacksmith, inventor and publisher who introduced printing to Europe with the printing press. His introduction of mechanical movable type printing to Europe started the Printing Revolution and is regarded as a milestone of the second millennium, ushering in the modern period of human history, it played a key role in the development of the Renaissance, the Age of Enlightenment, the scientific revolution and laid the material basis for the modern knowledge-based economy and the spread of learning to the masses. Gutenberg in 1439 was the first European to use movable type. Among his many contributions to printing are: the invention of a process for mass-producing movable type, his epochal invention was the combination of these elements into a practical system that allowed the mass production of printed books and was economically viable for printers and readers alike. Gutenberg's method for making type is traditionally considered to have included a type metal alloy and a hand mould for casting type.
The alloy was a mixture of lead and antimony that melted at a low temperature for faster and more economical casting, cast well, created a durable type. In Renaissance Europe, the arrival of mechanical movable type printing introduced the era of mass communication which permanently altered the structure of society; the unrestricted circulation of information—including revolutionary ideas—transcended borders, captured the masses in the Reformation and threatened the power of political and religious authorities. Across Europe, the increasing cultural self-awareness of its people led to the rise of proto-nationalism, accelerated by the flowering of the European vernacular languages to the detriment of Latin's status as lingua franca. In the 19th century, the replacement of the hand-operated Gutenberg-style press by steam-powered rotary presses allowed printing on an industrial scale, while Western-style printing was adopted all over the world, becoming the sole medium for modern bulk printing.
The use of movable type was a marked improvement on the handwritten manuscript, the existing method of book production in Europe, upon woodblock printing, revolutionized European book-making. Gutenberg's printing technology spread throughout Europe and the world, his major work, the Gutenberg Bible, was the first printed version of the Bible and has been acclaimed for its high aesthetic and technical quality. Gutenberg was born in the German city of Mainz, the youngest son of the patrician merchant Friele Gensfleisch zur Laden, his second wife, Else Wyrich, the daughter of a shopkeeper, it is assumed. According to some accounts, Friele was a goldsmith for the bishop at Mainz, but most he was involved in the cloth trade. Gutenberg's year of birth is not known, but it was sometime between the years of 1394 and 1404. In the 1890s the city of Mainz declared his official and symbolic date of birth to be June 24, 1400. John Lienhard, technology historian, says "Most of Gutenberg's early life is a mystery.
His father worked with the ecclesiastic mint. Gutenberg grew up knowing the trade of goldsmithing." This is supported by historian Heinrich Wallau, who adds, "In the 14th and 15th centuries his claimed a hereditary position as... retainers of the household of the master of the archiepiscopal mint. In this capacity they doubtless acquired considerable knowledge and technical skill in metal working, they supplied the mint with the metal to be coined, changed the various species of coins, had a seat at the assizes in forgery cases."Wallau adds, "His surname was derived from the house inhabited by his father and his paternal ancestors'zu Laden, zu Gutenberg'. The house of Gänsfleisch was one of the patrician families of the town, tracing its lineage back to the thirteenth century." Patricians in Mainz were named after houses they owned. Around 1427, the name zu Gutenberg, after the family house in Mainz, is documented to have been used for the first time. In 1411, there was an uprising in Mainz against the patricians, more than a hundred families were forced to leave.
As a result, the Gutenbergs are thought to have moved to Eltville am Rhein, where his mother had an inherited estate. According to historian Heinrich Wallau, "All, known of his youth is that he was not in Mainz in 1430, it is presumed that he migrated for political reasons to Strasbourg, where the family had connections." He is assumed to have studied at the University of Erfurt, where there is a record of the enrolment of a student called Johannes de Altavilla in 1418—Altavilla is the Latin form of Eltville am Rhein. Nothing is now known of Gutenberg's life for the next fifteen years, but in March 1434, a letter by him indicates that he was living in Strasbourg, where he had some relatives on his mother's side, he appears to have been a goldsmith member enrolled in the Strasbourg militia. In 1437, there is evidence that he was instructing a wealthy tradesman on polishing gems, but where he had acquired this knowledge is unknown. In 1436/37 his name comes up in court in connection with a broken promise of marriage to a woman from Strasbourg, Ennelin.
Whether the marriage took place is not reco
Rotary printing press
A rotary printing press is a printing press in which the images to be printed are curved around a cylinder. Printing can be done on a large number of substrates, including paper and plastic. Substrates can be sheet feed or unwound on a continuous roll through the press to be printed and further modified if required. Printing presses that use continuous rolls are sometimes referred to as "web presses". William Nicholson filed a 1790 patent for a rotary press; the rotary press itself is an evolution of the cylinder press patented by William Nicholson, invented by Beaucher of France in the 1780s and by Friedrich Koenig in the early 19th century. Rotary drum printing was invented by Richard March Hoe in 1843. An 1844 patent replaced the reciprocating platforms used in earlier designs with a fixed platform served by rotating drums, through a series of advances a complete rotary printing press was perfected in 1846, patented in 1847, it appeared in Edinburgh in 1851 and traveled to London where it was used by the Times newspaper in 1853, where it traveled to France in 1866 and Germany in 1873.
By the time it reached Spain in 1885 it had become common use. Some sources describe the Parisian Hippolyte Auguste Marinoni as the inventor of the Rotary printing press, but this was the subject of a patent dispute, decided in Hoe's favor. A. S. Abell of the Baltimore Sun was the first American user of the rotary press. Today, there are three main types of rotary presses. Although the three types use cylinders to print, they vary in their method. In Offset lithography, the image is chemically applied to a plate through exposure of photosensitive layers on the plate material. Lithography is based on the fact that water and oil do not mix, which enables the planographic process to work. In the context of a printing plate, a wettable surface may be termed hydrophilic and a non-wettable surface hydrophobic. Gravure is a process in which small cells or holes are etched into a copper cylinder, which are able to be filled with ink. All the colours are etched in different angles, thus while printing every colour is placed in proper position to give the appropriate image.
Flexography is a relief system in which a raised image is created on a polymer based plate. In stamp collecting, rotary-press-printed stamps are sometimes a different size than stamps printed with a flat plate; this happens because the stamp images are further apart on a rotary press, which makes the individual stamps larger. Wetting
MAN SE MAN AG, is a German mechanical engineering company and parent company of the MAN Group. It is a subsidiary of automaker Volkswagen AG. MAN SE is based in Munich, its primary output is for the automotive industry heavy trucks. Further activities include the production of diesel engines for various applications, like marine propulsion, turbomachinery. MAN supplies trucks, diesel engines and turbomachinery. In 2016, its 53,824 employees generated annual sales of around €13.6 billion. MAN SE is owned in majority by Volkswagen AG, it is a producer of Commercial Vehicles, through its MAN Truck & Bus and MAN Latin America divisions, participation in the manufacturer Sinotruk. MAN traces its origins back to 1758, when the "St. Antony" ironworks commenced operation in Oberhausen, as the first heavy-industry enterprise in the Ruhr region. In 1808, the three ironworks "St. Antony", "Gute Hoffnung", "Neue Essen" merged, to form the Hüttengewerkschaft und Handlung Jacobi, renamed Gute Hoffnungshütte. In 1840, the German engineer Ludwig Sander founded in Augsburg the first predecessing enterprise of MAN in Southern Germany: the "Sander'sche Maschinenfabrik."
It firstly became the "C. Reichenbach'sche Maschinenfabrik", named after the pioneer of printing machines Carl August Reichenbach, on the "Maschinenfabrik Augsburg"; the branch Süddeutsche Brückenbau A. G. was founded when the company in 1859 was awarded the contract for the construction of the railway bridge over the Rhine at Mainz. In 1898, the companies Maschinenbau-AG Nürnberg and Maschinenfabrik Augsburg AG merged to form Vereinigte Maschinenfabrik Augsburg und Maschinenbaugesellschaft Nürnberg A. G. Augsburg. In 1908, the company was renamed Maschinenfabrik Augsburg Nürnberg AG, or in short, M·A·N. While the focus remained on ore mining and iron production in the Ruhr region, mechanical engineering became the dominating branch of business in Augsburg and Nuremberg. Under the direction of Heinrich von Buz, Maschinenfabrik Augsburg grew from a medium-sized business of 400 employees into a major enterprise with a workforce of 12,000 by the year 1913. Locomotion and steel building were the big topics of this phase.
The early predecessors of MAN were responsible for numerous technological innovations. The success of the early MAN entrepreneurs and engineers like Heinrich Gottfried Gerber, was based on a great openness towards new technologies, they constructed the Wuppertal monorail and the first spectacular steel bridges like the Großhesseloher Brücke in Munich in 1857 and the Müngsten railway bridge between 1893 and 1897. The invention of the rotary printing press allowed the copious printing of books and newspapers and since 1893, Rudolf Diesel puzzled for four years with future MAN engineers in a laboratory in Augsburg until his first Diesel engine was completed and functional. During 1921, the majority of M. A. N. was taken over by Sterkrade. Through well-directed equities and acquisitions of processing industries, e.g. Deutsche Werft, Deggendorfer Werft und Eisenbau, MAN advanced to a nationwide operating enterprise, with a workforce of 52,000 by 1921. MAN produced tractors by the name MAN Ackerdiesel between.
The decision for tractors production was made due to increasing demand from eastern Germany. At the same time the GHH's economic situation worsened; the causes for this were, among others, the reparations after World War I, the occupation of the Ruhr region and the world economic crisis. In only two years the number of MAN employees sank from 14,000 in the year 1929/30 to 7,400 in 1931/32. While the civil business was collapsing, the military business increased with the armament under the National Socialist regime. GHH/MAN enterprises supplied diesel engines for submarines, cylinders for projectiles and artillery of every description. MAN produced gun parts, including Mauser Karabiner 98k rifle bolts, their Waffenamt code was WaA53, ordnance code was "coc". The MAN works in Augsburg, which produced diesel engines for U-boats, the MAN works in Nuremberg, which built 40 percent of Germany's Panther tanks, were the target of massive Allied bombing attacks during World War II. After the end of World War II the allies split up the GHH group.
A vertical integration in which mining and steel production are consolidated was not allowed any more. The "Gutehoffnungshütte", together with the MAN firms of Southern Germany, therefore concentrated on engineering, plant construction, commercial vehicles and printing machines; this process has been supported by strategic dispositions. In 1982/83 the "Gutehoffnungshütte" plunged into a deep corporate crisis; the enterprise suffered from the late effects of a bad economic situation. This was displayed by the dramatic downturn of the commercial vehicles sales figures. Besides e
Augsburg is a city in Swabia, Germany. It is a university town and regional seat of the Regierungsbezirk Schwaben. Augsburg is an urban home to the institutions of the Landkreis Augsburg, it is the third-largest city in Bavaria with a population of 300,000 inhabitants, with 885,000 in its metropolitan area. After Neuss and Trier, Augsburg is Germany's third oldest city, founded in 15 BC by the Romans as Augusta Vindelicorum, named after the Roman emperor Augustus, it was a Free Imperial City from 1276 to 1803 and the home of the patrician Fugger and Welser families that dominated European banking in the 16th century. The city played a leading role in the Reformation as the site of the 1530 Augsburg Confession and 1555 Peace of Augsburg; the Fuggerei, the oldest social housing complex in the world, was founded in 1513 by Jakob Fugger. Augsburg lies on the Singold; the oldest part of the city and the southern quarters are on the northern foothills of a high terrace, which emerged between the steep rim of the hills of Friedberg in the east and the high hills of the west.
In the south extends the Lechfeld, an outwash plain of the post ice age between the rivers Lech and Wertach, where rare primeval landscapes were preserved. The Augsburg city forest and the Lech valley heaths today rank among the most species-rich middle European habitats. On Augsburg borders the nature park Augsburg Western Woods - a large forestland; the city itself is heavily greened. As a result, in 1997 Augsburg was the first German city to win the Europe-wide contest Entente Florale for Europe's greenest and most livable city. Augsburg is surrounded by the counties Landkreis Augsburg in the west and Aichach-Friedberg in the east; the Suburb are Friedberg, Königsbrunn, Neusäß, Diedorf Neighbouring municipalities:Rehling, Kissing, Merching, Gessertshausen The city was founded in 15 BC by Drusus and Tiberius as Augusta Vindelicorum, on the orders of their stepfather Emperor Augustus. The name means "Augusta of the Vindelici"; this garrison camp soon became the capital of the Roman province of Raetia.
Early development was due to a 400-year affiliation with the Roman Empire because of its excellent military and geographic position at the convergence of the Alpine rivers Lech and Wertach, with direct access to most important Alpine passes. Thus, Augsburg was the intersection of many important European east-west and north-south connections, which evolved as major trade routes of the Middle Ages. Around 120 AD Augsburg became the capital of the Roman province Raetia. Augsburg was sacked by the Huns in the 5th century AD, by Charlemagne in the 8th century, by Welf of Bavaria in the 11th century, but arose each time to greater prosperity. Augsburg was granted the status of a Free Imperial City on March 9, 1276 and from until 1803, it was independent of its former overlord, the Prince-Bishop of Augsburg. Frictions between the city-state and the prince-bishops were to remain frequent however after Augsburg became Protestant and curtailed the rights and freedoms of Catholics. With its strategic location at an intersection of trade routes to Italy, the Free Imperial City became a major trading center.
Augsburg produced large quantities of woven goods and textiles. Augsburg became the base of two banking families that rose to great prominence, the Fuggers and the Welsers; the Fugger family donated the Fuggerei part of the city devoted to housing for needy citizens in 1516, which remains in use today. In 1530, the Augsburg Confession was presented to the Holy Roman Emperor at the Diet of Augsburg. Following the Peace of Augsburg in 1555, after which the rights of religious minorities in imperial cities were to be protected, a mixed Catholic–Protestant city council presided over a majority Protestant population. Religious peace in the city was maintained despite increasing Confessional tensions until the Thirty Years' War. In 1629, Holy Roman Emperor Ferdinand II issued the Edict of Restitution, which restored the legal situation of 1552 and again curtailed the rights of the Protestant citizens; the inequality of the Edict of Restitution was rescinded when in April 1632, the Swedish army under Gustavus Adolphus captured Augsburg without resistance.
In 1634, the Swedish army was routed at nearby Nördlingen. By October 1634, Catholic troops had surrounded Augsburg; the Swedish garrison refused to surrender and a siege ensued through the winter of 1634/35 and thousands died from hunger and disease. According to J. N. Hays, "In the period of the Swedish occupation and the Imperial siege the population of the city was reduced from about 70,000 to about 16,000, with typhus and plague playing major roles." In 1686, Emperor Leopold I formed the League of Augsburg, termed by the English as the "Grand Alliance" after England joined in 1689: a European coalition, consisting of Austria, Brandenburg, the Holy Roman Empire, the Palatinate of the Rhine, Savoy, Spain and the United Provinces. It was formed to defend the Palatinate from France; this organization fought against France in the Nine Years War. Augsburg's peak boom years occurred during the 15th and 16th centuries thanks to the bank and metal businesses of the merchant families Fugger and Welser, who held a local near total monopoly on their respective industries.
Augsburg's wealth attracted artists seeking patrons and became a creative centre for famous painters and musicia
Boiler (power generation)
A boiler or steam generator is a device used to create steam by applying heat energy to water. Although the definitions are somewhat flexible, it can be said that older steam generators were termed boilers and worked at low to medium pressure but, at pressures above this, it is more usual to speak of a steam generator. A boiler or steam generator is used; the form and size depends on the application: mobile steam engines such as steam locomotives, portable engines and steam-powered road vehicles use a smaller boiler that forms an integral part of the vehicle. A notable exception is the steam-powered fireless locomotive, where separately-generated steam is transferred to a receiver on the locomotive; the steam generator or boiler is an integral component of a steam engine when considered as a prime mover. However it needs to be treated separately, as to some extent a variety of generator types can be combined with a variety of engine units. A boiler incorporates a furnace in order to burn the fuel and generate heat.
The generated heat is transferred to water to make the process of boiling. This produces saturated steam at a rate which can vary according to the pressure above the boiling water; the higher the furnace temperature, the faster the steam production. The saturated steam thus produced can either be used to produce power via a turbine and alternator, or else may be further superheated to a higher temperature. Any remaining heat in the combustion gases can either be evacuated or made to pass through an economiser, the role of, to warm the feed water before it reaches the boiler. For the first Newcomen engine of 1712, the boiler was little more than large brewer's kettle installed beneath the power cylinder; because the engine's power was derived from the vacuum produced by condensation of the steam, the requirement was for large volumes of steam at low pressure hardly more than 1 psi The whole boiler was set into brickwork which retained some heat. A voluminous coal fire was lit on a grate beneath the dished pan which gave a small heating surface.
In models, notably by John Smeaton, heating surface was increased by making the gases heat the boiler sides, passing through a flue. Smeaton further lengthened the path of the gases by means of a spiral labyrinth flue beneath the boiler; these under-fired boilers were used in various forms throughout the 18th Century. Some were of round section. A longer version on a rectangular plan was developed around 1775 by Watt; this is what is today known as a three-pass boiler, the fire heating the underside, the gases passing through a central square-section tubular flue and around the boiler sides. An early proponent of the cylindrical form was the British engineer John Blakey, who proposed his design in 1774. Another early proponent was the American engineer, Oliver Evans, who rightly recognised that the cylindrical form was the best from the point of view of mechanical resistance and towards the end of the 18th Century began to incorporate it into his projects. Inspired by the writings on Leupold's "high-pressure" engine scheme that appeared in encyclopaedic works from 1725, Evans favoured "strong steam" i.e. non condensing engines in which the steam pressure alone drove the piston and was exhausted to atmosphere.
The advantage of strong steam as he saw it was that more work could be done by smaller volumes of steam. To this end he developed a long cylindrical wrought iron horizontal boiler into, incorporated a single fire tube, at one end of, placed the fire grate; the gas flow was reversed into a passage or flue beneath the boiler barrel divided to return through side flues to join again at the chimney. Evans incorporated his cylindrical boiler into several engines, both mobile. Due to space and weight considerations the latter were one-pass exhausting directly from fire tube to chimney. Another proponent of "strong steam" at that time was Richard Trevithick, his boilers worked at 40–50 psi and were at first of hemispherical cylindrical form. From 1804 onwards Trevithick produced a small two-pass or return flue boiler for semi-portable and locomotive engines; the Cornish boiler developed around 1812 by Richard Trevithick was both stronger and more efficient than the simple boilers which preceded it. It consisted of a cylindrical water tank around 27 feet long and 7 feet in diameter, had a coal fire grate placed at one end of a single cylindrical tube about three feet wide which passed longitudinally inside the tank.
The fire was tended from one end and the hot gases from it travelled along the tube and out of the other end, to be circulated back along flues running along the outside a third time beneath the boiler barrel before being expelled into a chimney. This was improved upon by another 3-pass boiler, the Lancashire boiler which had a pair of furnaces in separate tubes side-by-side; this was an important improvement since each furnace could be stoked at different times, allowing one to be cleaned while the o