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42-700: Merton Street is a cobbled street in central Oxford , England. It joins the High Street at its northeastern end, between the Ruskin School of Drawing and Fine Art (together with the Examination Schools ) and the Eastgate Hotel at the historic east gate of the city. It then runs east–west, parallel and to the south of the High Street for most of its length. Merton College , one of Oxford's older colleges,

84-462: A certain degree of flexibility to adapt to shifting ground or other changing conditions. Cement mortar is harder and allows little flexibility. The contrast can cause brickwork to crack where the two mortars are present in a single wall. Lime mortar is considered breathable in that it will allow moisture to freely move through and evaporate from the surface. In old buildings with walls that shift over time, cracks can be found which allow rain water into

126-439: A lime must be stored as a dry powder. Alternatively, a pozzolanic material such as calcined clay or brick dust may be added to the mortar mix. Addition of a pozzolanic material will make the mortar set reasonably quickly by reaction with the water. It would be problematic to use Portland cement mortars to repair older buildings originally constructed using lime mortar. Lime mortar is softer than cement mortar, allowing brickwork

168-477: A popular material for paving newly pedestrianised streets in Europe. In this case, the noisy nature of the surface is an advantage as pedestrians can hear approaching vehicles. The visual cues of the cobblestones also clarify that the area is more than just a normal street. The use of cobblestones/setts is also considered to be a more "upmarket" roadway solution, having been described as "unique and artistic" compared to

210-574: A reason it was used as the typical mortar in ancient, brick arch and vault construction. Gypsum mortar is not as durable as other mortars in damp conditions. In the Indian subcontinent , multiple cement types have been observed in the sites of the Indus Valley civilization , with gypsum appearing at sites such as the Mohenjo-daro city-settlement, which dates to earlier than 2600 BCE. Gypsum cement that

252-760: A strong mortar that will also set under water. As the mortar hardens, the current atmosphere is encased in the mortar and thus provides a sample for analysis. Various factors affect the sample and raise the margin of error for the analysis. Radiocarbon dating of mortar began as early as the 1960s, soon after the method was established (Delibrias and Labeyrie 1964; Stuiver and Smith 1965; Folk and Valastro 1976). The very first data were provided by van Strydonck et al. (1983), Heinemeier et al.(1997) and Ringbom and Remmer (1995). Methodological aspects were further developed by different groups (an international team headed by Åbo Akademi University , and teams from CIRCE, CIRCe, ETHZ, Poznań, RICH and Milano-Bicocca laboratory. To evaluate

294-535: A structure with Portland cement. As a general rule, however, Portland cement should not be used for the repair or repointing of older buildings built in lime mortar, which require the flexibility, softness and breathability of lime if they are to function correctly. In the United States and other countries, five standard types of mortar (available as dry pre-mixed products) are generally used for both new construction and repair. Strengths of mortar change based on

336-428: A traditional brick, block or stone wall. It is mainly designed for repairing concrete structures. The use of recovered plastics in mortars is being researched and is gaining ground. Depolymerizing PET to use as a polymeric binder to enhance mortars is actively being studied. The setting speed can be increased by using impure limestone in the kiln , to form a hydraulic lime that will set on contact with water. Such

378-485: Is a natural building material based on cobble -sized stones, and is used for pavement roads , streets, and buildings. Setts , also called Belgian blocks, are often referred to as "cobbles", although a sett is distinct from a cobblestone by being quarried and shaped into a regular form, while cobblestones are naturally occurring forms less uniform in size. It has been used across various cultures for millennia, particularly in Europe, and became especially prominent during

420-799: Is also a cluster of cobblestone buildings in the Town of Paris , Ontario . In addition to homes, cobblestones were used to build barns, stagecoach taverns, smokehouses, stores, churches, schools, factories, and cemetery markers. The only public cobblestone building in the US is the Alexander Classical School , located in Alexander, New York . Cobblestone may not be accessible for disabled people, particularly wheelchair users. Wheelchair users and other disabled people may opt to avoid streets and sidewalks made with cobblestone. Some European cities, such as Breda in

462-489: Is situated to the south of the street. To the west of Merton, Corpus Christi College , one of Oxford's smallest colleges, also fronts onto the street. At the very western end, actually in Oriel Square , is an entrance to Christ Church , Oxford's largest college. At the eastern end can be found the notorious 'Pink House', as well as an entrance to University College . Logic Lane (through University College, which backs onto

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504-542: The Netherlands , have tried to preserve their historic aesthetic while also making cobblestone pavement more accessible for disabled people by slicing the cobblestone to be flat on the surface. The United States Access Board does not specify which materials a sidewalk must be made of in order to be ADA compliant, but does state that "cobblestones can significantly impede wheelchair movement" and that sidewalks must not have surface variances of greater than one inch. Due to

546-572: The 20th century. Siegfried Sassoon briefly took rooms in no 14 during 1919, on the recommendation of Lady Ottoline Morrell . The historian Michael Brock (1920–2014) and his wife (and co-editor) Eleanor lived in the street in the early 1950s. The academic and author J. R. R. Tolkien had rooms in Merton Street towards the end of his life in the early 1970s. 51°45′05″N 1°15′06″W  /  51.7514°N 1.2518°W  / 51.7514; -1.2518 Cobbled street Cobblestone

588-471: The accessibility challenges of cobblestone, the Federal Highway Administration recommends against the use of cobblestone and bricks in its accessibility guide for sidewalks and crosswalks. Mortar (masonry) Cement mortar becomes hard when it cures, resulting in a rigid aggregate structure; however, the mortar functions as a weaker component than the building blocks and serves as

630-403: The advent of asphalt and concrete in the 20th century, the use of cobblestones declined. These newer materials were cheaper and easier to install, leading to the replacement of many cobblestone streets. However, cobblestone streets have been preserved in many historic districts around the world, valued for their historical significance and aesthetic charm. In recent decades, cobblestones have become

672-570: The alternate letters of the words " M a S o N w O r K ". Polymer cement mortars (PCM) are the materials which are made by partially replacing the cement hydrate binders of conventional cement mortar with polymers. The polymeric admixtures include latexes or emulsions , redispersible polymer powders, water-soluble polymers, liquid thermoset resins and monomers. Although they increase cost of mortars when used as an additive, they enhance properties. Polymer mortar has low permeability that may be detrimental to moisture accumulation when used to repair

714-401: The blockage of the High Street to normal traffic. To the west it continues through Oriel Square, where Oriel College is located. Despite being cobbled, the street has been repaired by Oxford City Council using asphalt . The part of modern-day Merton Street adjoining the High Street used to be known as Coach & Horses Lane , named after a public house on the west side of the lane. From

756-482: The cobbles outside the house of a sick or dying person to dampen the sound. In rural areas, cobblestones were sometimes used to pave important roads, particularly those leading to and from major cities. In England, it was commonplace since ancient times for flat stones with a flat narrow edge to be set on edge to provide an even paved surface. This was known as a 'pitched' surface and was common all over Britain, as it did not require rounded pebbles. Pitched surfaces predate

798-409: The early 18th to the late 19th century, it became known as King Street . The rest of the street (the part running east–west) was originally known as St John Baptist's Street , named after the church which is now Merton College's chapel. In 1751, the whole street had become King Street, but by 1772 just the east–west part was called Merton Street. The entire street became known as Merton Street only in

840-405: The environmental advantage of being permeable paving , and of moving rather than cracking with movements in the ground. The fact that carriage wheels , horse hooves and even modern automobiles make a lot of noise when rolling over cobblestone paving might be thought a disadvantage, but it has the advantage of warning pedestrians of their approach. In England, the custom was to strew straw over

882-467: The first evidence of humans using a form of mortar was at the Mehrgarh of Baluchistan in what is today Pakistan, built of sun-dried bricks in 6500 BCE. Gypsum mortar, also called plaster of Paris, was used in the construction of many ancient structures. It is made from gypsum, which requires a lower firing temperature. It is therefore easier to make than lime mortar and sets up much faster, which may be

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924-470: The form of plaster of Paris are used particularly in the repair and repointing of historic buildings and structures, so that the repair materials will be similar in performance and appearance to the original materials. Several types of cement mortars and additives exist. The first mortars were made of mud and clay , as demonstrated in the 10th millennia BCE buildings of Jericho , and the 8th millennia BCE of Ganj Dareh . According to Roman Ghirshman ,

966-610: The increased traffic from carts, carriages, and pedestrians. Cobblestones were largely replaced by quarried granite setts (also known as Belgian block ) in the nineteenth century. Cobblestoned and "setted" streets gradually gave way to macadam roads and later to tarmac , and finally to asphalt concrete at the beginning of the 20th century. However, cobble­stones are often retained in historic areas, even for streets with modern vehicular traffic. Many older villages and cities in Europe are still paved with cobblestones or pitched. With

1008-460: The last ice age left numerous small, rounded cobblestones available for building. Pre-Civil War architecture in the region made heavy use of cobblestones for walls. Today, the fewer than 600 remaining cobblestone buildings are prized as historic locations, most of them private homes. Ninety percent of the cobblestone buildings in America can be found within a 75-mile radius of Rochester, New York. There

1050-491: The lime to set relatively quickly and even under water. Vitruvius , the Roman architect, spoke of four types of pozzolana. It is found in all the volcanic areas of Italy in various colours: black, white, grey and red. Pozzolana has since become a generic term for any siliceous and/or aluminous additive to slaked lime to create hydraulic cement. Finely ground and mixed with lime it is a hydraulic cement, like Portland cement, and makes

1092-462: The limestone blocks were bound by a mortar of mud and clay, or clay and sand. In later Egyptian pyramids, the mortar was made of gypsum , or lime. Gypsum mortar was essentially a mixture of plaster and sand and was quite soft. 2nd millennia BCE Babylonian constructions used lime or pitch for mortar. Historically, building with concrete and mortar next appeared in Greece . The excavation of

1134-484: The medieval and early modern periods. Today, cobblestone streets are often associated with historic preservation and are used in many cities to maintain the historical character of certain neighborhoods. During the medieval period , cobblestone streets became common in many European towns and cities. Cobblestones were readily available, as they were often naturally occurring stones found in riverbeds and fields. Their rounded shape made them easy to lay, and their durability

1176-492: The mix ratio for each type of mortar, which are specified under the ASTM standards. These premixed mortar products are designated by one of the five letters, M, S, N, O, and K. Type M mortar is the strongest, and Type K the weakest. The mix ratio is always expressed by volume of Portland cement : lime : sand {\displaystyle {\text{Portland cement : lime : sand}}} . These type letters are apparently taken from

1218-442: The normal asphalt road environment. In older U.S. cities such as Philadelphia , Boston , Pittsburgh , New York City , Chicago , San Francisco , New Castle , Portland (Maine) , Baltimore , Charleston , and New Orleans , many of the older streets are paved in cobblestones and setts (mostly setts); however, many such streets have been paved over with asphalt, which can crack and erode away due to heavy traffic, thus revealing

1260-847: The original stone pavement. In some places such as Saskatoon, Saskatchewan , Canada , as late as the 1990s some busy intersections still showed cobblestones through worn down sections of pavement. In Toronto streets using setts were used by streetcar routes and disappeared by the 1980s, but are still found in the Distillery District . Many cities in Latin America, such as Buenos Aires , Argentina ; Zacatecas and Guanajuato , in Mexico ; Old San Juan , Puerto Rico ; Vigan , Philippines ; and Montevideo , Uruguay , are well known for their many cobblestone streets, which are still operational and in good condition. They are still maintained and repaired in

1302-419: The sacrificial element in the masonry, because mortar is easier and less expensive to repair than the building blocks. Bricklayers typically make mortars using a mixture of sand , a binder , and water. The most common binder since the early 20th century is Portland cement , but the ancient binder lime (producing lime mortar ) is still used in some specialty new construction. Lime, lime mortar, and gypsum in

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1344-506: The street) and Magpie Lane , both narrow lanes, lead off the street to the north. Also located here is the Merton Street tennis court , a rare example of an extant real tennis court. To the south is Merton Grove (opposite Magpie Lane), providing pedestrian access between Merton College and Corpus Christi College to Christ Church Meadow to the south. The street is designated the A420 due to

1386-544: The structure. The lime mortar allows this moisture to escape through evaporation and keeps the wall dry. Re−pointing or rendering an old wall with cement mortar stops the evaporation and can cause problems associated with moisture behind the cement. Pozzolana is a fine, sandy volcanic ash . It was originally discovered and dug at Pozzuoli , nearby Mount Vesuvius in Italy, and was subsequently mined at other sites, too. The Romans learned that pozzolana added to lime mortar allowed

1428-516: The then Greek colony of Dicaearchia ( Pozzuoli ) near Naples, Italy. The Romans later improved the use and methods of making what became known as pozzolanic mortar and cement. Even later, the Romans used a mortar without pozzolana using crushed terra cotta , introducing aluminum oxide and silicon dioxide into the mix. This mortar was not as strong as pozzolanic mortar, but, because it was denser, it better resisted penetration by water. Hydraulic mortar

1470-574: The traditional manner, by placing and arranging granite stones by hand. In the Czech Republic , there are old cobblestone paths with colored marbles and limestones . The design with three colors (red/limestone, black/limestone, white/marble) has a long tradition in Bohemia . The cubes of the old ways are handmade. In the Finger Lakes Region of New York State, the retreat of the glaciers during

1512-463: The underground aqueduct of Megara revealed that a reservoir was coated with a pozzolanic mortar 12 mm thick. This aqueduct dates back to c. 500 BCE. Pozzolanic mortar is a lime based mortar, but is made with an additive of volcanic ash that allows it to be hardened underwater; thus it is known as hydraulic cement. The Greeks obtained the volcanic ash from the Greek islands Thira and Nisiros , or from

1554-567: The use of regularly-sized granite setts by more than a thousand years. Such pitched paving is quite distinct from that formed from rounded stones, although both forms are commonly referred to as 'cobbled' surfaces. Most surviving genuinely old 'cobbled' areas are in reality pitched surfaces. A cobbled area is known as a "causey", "cassay" or "cassie" in Scots (probably from causeway ). In the early modern period , cities like Paris, London, and Amsterdam began to pave their streets with cobblestones to manage

1596-509: Was " light grey and contained sand, clay, traces of calcium carbonate, and a high percentage of lime " was used in the construction of wells, drains, and on the exteriors of " important looking buildings ." Bitumen mortar was also used at a lower-frequency, including in the Great Bath at Mohenjo-daro. In early Egyptian pyramids, which were constructed during the Old Kingdom (~2600–2500 BCE),

1638-434: Was invented in 1794 by Joseph Aspdin and patented on 18 December 1824, largely as a result of efforts to develop stronger mortars. It was made popular during the late nineteenth century, and had by 1930 became more popular than lime mortar as construction material. The advantages of Portland cement is that it sets hard and quickly, allowing a faster pace of construction. Furthermore, fewer skilled workers are required in building

1680-462: Was not available in ancient China, possibly due to a lack of volcanic ash. Around 500 CE, sticky rice soup was mixed with slaked lime to make an inorganic−organic composite sticky rice mortar that had more strength and water resistance than lime mortar. It is not understood how the art of making hydraulic mortar and cement, which was perfected and in such widespread use by both the Greeks and Romans,

1722-573: Was then lost for almost two millennia. During the Middle Ages when the Gothic cathedrals were being built, the only active ingredient in the mortar was lime. Since cured lime mortar can be degraded by contact with water, many structures suffered over the centuries from wind-blown rain. Ordinary Portland cement mortar , commonly known as OPC mortar or just cement mortar, is created by mixing powdered ordinary Portland cement , fine aggregate and water. It

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1764-558: Was well-suited to the needs of growing urban centers. Cobblestones are typically either set in sand or similar material, or are bound together with mortar . Paving with cobblestones allows a road to be heavily used all year long. It prevents the build-up of ruts often found in dirt roads . It has the additional advantage of immediately draining water, and not getting muddy in wet weather or dusty in dry weather. Shod horses are also able to get better traction on stone cobbles, pitches or setts than tarmac or asphalt. Cobblestones set in sand have

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