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45-629: The Joseph Chamberlain Memorial Clock Tower , or colloquially Old Joe , is a clock tower and campanile located in Chancellor's court at the University of Birmingham , in the suburb of Edgbaston . It is the tallest free-standing clock tower in the world, although its actual height is the subject of some confusion. The university lists it variously as 110 metres (361 ft), 99 metres (325 ft), and 100 metres (328 ft) tall,

90-481: A mannequin , every hour. It was possible to re-program the length of day and night daily in order to account for the changing lengths of day and night throughout the year, and it also featured five robotic musicians who automatically play music when moved by levers operated by a hidden camshaft attached to a water wheel . Line (mains) synchronous tower clocks were introduced in the United States in

135-614: A clock added in 2002, has a roof height of 240 m (790 ft), and an antenna height of 272 m (892 ft). The Abraj Al Bait , a hotel complex in Mecca constructed in 2012, has the largest and highest clock face on a building in the world, with its Makkah Royal Clock Tower having an occupied height of 494.4 m (1,622 ft), and a tip height of 601 m (1,972 ft). The tower has four clock faces, two of which are 43 m (141 ft) in diameter, at about 400 m (1,300 ft) high. Repointing Repointing

180-788: A clock was put up in a clock tower, the medieval precursor to Big Ben , at Westminster , in 1288; and in 1292 a clock was put up in Canterbury Cathedral . The oldest surviving turret clock formerly part of a clock tower in Europe is the Salisbury Cathedral clock , completed in 130. A clock put up at St. Albans , in 1326, 'showed various astronomical phenomena'. Al-Jazari of the Artuqid dynasty in Upper Mesopotamia constructed an elaborate clock called

225-417: A dilute acid. The mortar will be broken down, and the type of mortar and sand used will be determined by color and texture. Another form of "wet chemical" analysis is the same process but the carbon dioxide gas that is given off by the digestion will be collected and the type of mortar will be determined by its volume. The amounts of each component will also be determined. The second method to analyzing mortar

270-625: A tower and therefore can be defined as any tower specifically built with one or more (often four) clock faces and that can be either freestanding or part of a church or municipal building such as a town hall . Not all clocks on buildings therefore make the building into a clock tower. The mechanism inside the tower is known as a turret clock . It often marks the hour (and sometimes segments of an hour) by sounding large bells or chimes , sometimes playing simple musical phrases or tunes. Some clock towers were previously built as Bell towers and then had clocks added to them. As these structures fulfil

315-444: Is "instrumental." There are several different forms of "instrumental" analysis; however, the most commonly used is thin section microscopy in which thin slices of mortar are examined by a transmitted light microscope. This process can provide more information than "wet-chemical" examination. Other examples of instrumental analysis are scanning electron microscopy , X-ray diffraction , and atomic absorption spectroscopy . Analysis

360-412: Is added. The process is continued until the mortar is flush with the masonry. High-lime mortar dries rapidly, so after it reaches a particular strength it needs to be sprayed with water to avoid chalking, poor adhesion, or poor durability. The structure is misted every two hours for two days, then every four hours for two days. It is important that the mortar stays wet for at least a couple of days while it

405-447: Is also called pointing , or pointing up , although these terms more properly refer to the finishing step in new construction. Tuckpointing is also commonly used as a synonym , though its formal definition is technically different. Traditionally, mortar was made with lime and sand, producing lime putty. In the early 20th century, masons began using Portland cement , a strong, fast drying cement. Masonry cement made its appearance in

450-399: Is an area on the structure out of plain sight where the owner or conservator can test the repointing methods they will use, the color of the mortar, and the skills of the mason. This will also be good to determine the types of tools that should be used, which will be discussed in the next paragraph. For a brick structure, the panel should not be any bigger than 3' x 3'. For other masonry units,

495-399: Is common to see cracking along old repairs because of the shrinkage of hard mortar and the seasonal flexing along the joint. Examining the structure before working will also help establish the strength and permeability of the original mortar in order to match the new. It helps to establish what the original components of the old mortar are in order to find the best match. It is essential that

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540-412: Is not solely based on lab work, however. There are important performances of mortar that can not be determined in a lab: original water content, rate of curing, weather conditions during original construction, method of mixing and placing the mortar, and cleanliness of sand. It is important to also match the color of the mortar. However, in the past lime mortar tended to be mixed on site with whatever sand

585-426: Is setting. The local conditions will control how long the structure should be kept wet, however. Burlap or plastic is placed over the repointed wall or structure. This keeps the building damp and eliminates direct sunlight. The burlap and the plastic are not resting against the structure, however. The burlap or plastic are anchored to the ground to avoid this. There are different ways to lay the mortar joint close to

630-406: Is the process of renewing the pointing, which is the external part of mortar joints , in masonry construction. Over time, weathering and decay cause voids in the joints between masonry units, usually in bricks , allowing the undesirable entrance of water. Water entering through these voids can cause significant damage through frost weathering and from salt dissolution and deposition . Repointing

675-607: The Birmingham Post reported that Chamberlain had announced to the University Council an anonymous gift of £50,000 (the donor in fact was Sir Charles Holcroft ). This anonymous gift was announced some two months later in the Birmingham Post as "to be intended for the erection of a tower in connection with the new buildings at Bournbrook at a cost estimated by the architects at £25,000. The tower, it

720-786: The Parliament of Canada in Ottawa , and the Zytglogge clock tower in the Old City of Bern , Switzerland . The tallest freestanding clock tower in the world is the Joseph Chamberlain Memorial Clock Tower (Old Joe) at the University of Birmingham in Birmingham , United Kingdom. The tower stands at 100 metres (330 feet) tall and was completed in 1908. The clock tower of Philadelphia City Hall

765-437: The "castle clock" and described it in his Book of Knowledge of Ingenious Mechanical Devices in 1206. It was about 3.3 metres (11 feet) high, and had multiple functions alongside timekeeping . It included a display of the zodiac and the solar and lunar paths, and a pointer in the shape of the crescent moon that travelled across the top of a gateway , moved by a hidden cart and causing automatic doors to open, each revealing

810-988: The 1920s. Some clock towers have become famous landmarks. Prominent examples include Elizabeth Tower built in 1859, which houses the Great Bell (generally known as Big Ben ) in London , the tower of Philadelphia City Hall , the Rajabai Tower in Mumbai , the Spasskaya Tower of the Moscow Kremlin , the Torre dell'Orologio in the Piazza San Marco in Venice , Italy , the Peace Tower of

855-446: The 1930s, which is a combination of Portland cement and ground limestone . ‹The template How-to is being considered for merging .›   Before starting any actual work, building owners examine the masonry units, mortar, and the techniques used in the original construction. They try to identify the true problem they are facing and find out what were the causes of the deterioration or cracks. If there are cracks or problems in

900-540: The SW corner. The tower was built from the inside, without scaffolding, up to the level of the balcony. It is built of Red Accrington brick with Darley Dale dressings and tapers from 29 ft (8.8 m) square to 23 ft (7.0 m) below the balcony. Owing to its having been built from the inside it was not pointed and had to be pointed in 1914 and was subsequently repointed in 1957 and 1984–85. Its weight, solid brick corners linked by four courses of brick resists

945-667: The University itself. Designed as part of the initial phase of the Edgbaston campus by architects Aston Webb and Ingress Bell , the tower was constructed between 1900–1908, and stood at the centre of a semicircle of matching red brick buildings. The tower is modelled on the Torre del Mangia in Siena . The original tower designs were amended due to Chamberlain's great admiration for the Italian city's campanile . On 1 October 1905,

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990-426: The actual bricks or stone masonry there could be a larger problem that also needs to be addressed. If there is a larger issue, repointing may cause further damage. If a historic structure needs repointing, building owners usually hire an architectural historian or conservator to help pinpoint the issues. If the crack is smaller than 2mm and not causing any major defects, then it is better to leave it and not repoint. It

1035-552: The bell inside the tower). There are many structures that may have clocks or clock faces attached to them and some structures have had clocks added to an existing structure. According to the Council on Tall Buildings and Urban Habitat a structure is defined as a building if at least fifty percent of its height is made up of floor plates containing habitable floor area. Structures that do not meet this criterion, are defined as towers . A clock tower historically fits this definition of

1080-430: The bottom brick and recesses back as it goes up towards the upper brick. The third, recessed, is when the mortar sits back from the face of the brick. There is also tuckpointing , where a mortar of a contrasting colour is 'tucked' into the masonry joint. If the color of the new mortar is still not similar to the old mortar after repointing and setting, the non-repointed areas of the structure can be cleaned. This may bring

1125-439: The clock, the face of which is 5.25 m (17.2 ft) across, the largest bell weighs 13,619 pounds (6,177.5 kg) with all the bells together weighing 20 long tons (20 tonnes); the minute hand is 4.1 m (13 ft 5 in) long, the hour hand is 2 ft (61 cm) across, the pendulum is 15 ft (4.6 m) long. The clock hands are made out of sheet copper . There are ten floors served by an electrical lift in

1170-430: The colors closer together. To do this, a low pressure water jet is used to clean the old pointing. A high powered water jet is not to be used because this could damage the masonry and mortar. Chemicals are also not used with the water because this could be harmful to the masonry or mortar. However, if chemicals are used, the structure is rinsed afterwards with fresh water and natural or nylon brushes. Another method to match

1215-416: The definition of a tower they can be considered to be clock towers. Although clock towers are today mostly admired for their aesthetics, they once served an important purpose. Before the middle of the twentieth century, most people did not have watches, and prior to the 18th century even home clocks were rare. The first clocks did not have faces, but were solely striking clocks , which sounded bells to call

1260-411: The edge of the brick. Some contractors bring the mortar to the very edge, flush with the face of the brick. Others leave it recessed back to allow water to shed off the building. There are three types of recessed mortar: bucket handle, weatherstruck, and simply recessed. The bucket handle is when the mortar is in a curve shape away from the face of the brick. Weatherstruck is when the mortar starts close to

1305-496: The first Chancellor of the University (with the commemoration being carved into the stone at the tower's base), although one of the original suggested names for the clock tower was the "Poynting Tower", after one of the earliest professors at the University, Professor John Henry Poynting . A prominent landmark in Birmingham , the grade II* listed tower can be seen for miles around the campus , and has become synonymous with

1350-425: The joint, or to the point where sound mortar is reached. Removal of old mortar between joints is done carefully to avoid damage to masonry units. On buildings with soft materials, such as under-fired brick, lime mortar , or terra cotta, removal by hand is often the most effective to avoid damage. Hard Portland cement mortar is usually removed with a grinder or power circular masonry blade, taking care not to damage

1395-433: The last of which is supported by other sources. In a lecture in 1945, Mr C. G. Burton, secretary of the University, stated that "the tower stands 329 ft [100 m] high, the clock dials measure 17 ft [5.2 m] in diameter, the length of the clock hands are 10 and 6 ft [3.0 and 1.8 m], and the bell weighs 5 long tons [5.1 tonnes]". The tower was built to commemorate Joseph Chamberlain ,

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1440-400: The masonry units because it will not have give. Rather than the mortar relieving the stress, the masonry units will, thus suffering further damage such as cracking or spalling. In spallation , the face or outer section of a masonry unit breaks away from the rest of the unit. This will require expensive and laborious repairs. So for example, if a soft lime -based mortar was originally used,

1485-419: The masonry units. After the mortar has been cut out, the joints are vacuumed or brushed clean. After vacuuming, the remaining debris is removed with a water jet from the top of the masonry area down. The areas with the deepest recession of mortar are filled first. The mortar is placed in several layers, starting with the first layer of 1/4 inch. It is hardened to a desired strength then another 1/4 inch layer

1530-505: The masonry units. Vertical joints or thin joints are done by hand or with small power chisels." If a power saw needs to be used, it's only used on wide and uniform horizontal joints and in the middle of the joint. A hammer and chisel are then used for the rest of the mortar, closer to the masonry units. Caulking cutters with diamond blades are an acceptable power tool to remove mortar in wide horizontal joints. They are slow, have no rotation, and vibrate so they are likely to cause less damage to

1575-411: The mortar used for repointing have similar performance characteristics to the original mortar used in a building. Such performance characteristics include permeability, compressive strength , and coefficient of thermal expansion . The mortar must have greater vapor permeability and softer compressive strength than the original mortar. The mortar should also not be stronger (in compressive strength) than

1620-421: The most appropriate repointing mortar is likely to also contain a large amount of lime. An architectural conservator can perform a mortar analysis in order to make recommendations for replacement mortar that is both physically and aesthetically compatible with the building. There are two common methods of analyzing mortar. The first is called "wet chemical" in which a sample of mortar is crushed and mixed with

1665-450: The overturning wind forces. The original design for Old Joe is thought to have been based upon St Mark's Campanile in Venice , the latter having served as the inspiration for Sather Tower at University of California, Berkeley . The final design is thought to have been inspired by Torre del Mangia which is of similar design but for the clock being placed towards the bottom of the tower. David Lodge 's novel Changing Places tells

1710-664: The story of exchange of professors between the universities of Rummidge and Euphoric State, Plotinus (thinly disguised fictional versions of Birmingham and Berkeley), which in the book both have replicas of the Leaning Tower of Pisa on campus. Clock tower Clock towers are a common sight in many parts of the world with some being iconic buildings. One example is the Elizabeth Tower in London (usually called " Big Ben ", although strictly this name belongs only to

1755-477: The surrounding community to work or to prayer. They were therefore placed in towers so the bells would be audible for a long distance. Clock towers were placed near the centres of towns and were often the tallest structures there. As clock towers became more common, the designers realized that a dial on the outside of the tower would allow the townspeople to read the time whenever they wanted. The use of clock towers dates back to antiquity . The earliest clock tower

1800-401: The test panel can be a little larger. It is also important to pick the right season to do the repointing. Extremely high or low temperatures can cause rapid drying which can have negative effects on the mortar, masonry units, and the structure itself. After examination, the next step is cutting away the old mortar. The old mortar is removed to a depth equal to or slightly more than the width of

1845-674: Was completed in the Jewellery Quarter area of the city. However, Old Joe is still one of the fifty tallest buildings in the UK . The asteroid 10515 Old Joe , discovered in 1989, is named in the clock tower's honour. There is a superstition that if students walk through the tower's archway when it chimes, that they will fail their degree. The base is solid concrete, 50 ft (15.2 m) square by 10 ft (3.0 m) thick, with foundations that extend 328 ft (100 m) below ground to ensure stability. Joyce of Whitchurch built

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1890-414: Was locally available. Since the sand influences the color of the lime mortar, colors of pointing mortar can vary dramatically from district to district. Weathering of the new mortar will also match it to the old mortar. The tooling should also match the tooling of the historic mortar. Again, before starting any work, the methods and materials for the repointing will be applied in a test panel. A test panel

1935-620: Was part of the tallest building in the world from 1894, when the tower was topped out and the building partially occupied, until 1908. Taller buildings have had clock faces added to their existing structure such as the Palace of Culture and Science in Warsaw , with a clock added in 2000. The building has a roof height of 187.68 m (615.7 ft), and an antenna height of 237 m (778 ft). The NTT Docomo Yoyogi Building in Tokyo , with

1980-560: Was suggested, would be upwards of 300 ft (91.4 m) in height, and would not only form the main architectural feature of the University but would be useful in connection with the Physics Department and as a record tower. In 1940, Sir Mark Oliphant used the tower for radar experiments. The tower remained the tallest structure in Birmingham until 1965, when construction on the 152 m (498.7 ft) tall BT Tower

2025-649: Was the Tower of the Winds in Athens , which featured eight sundials and was created in the 1st century BC during the period of Roman Greece . In its interior, there was also a water clock (or clepsydra), driven by water coming down from the Acropolis . In Song dynasty China , an astronomical clock tower was designed by Su Song and erected at Kaifeng in 1088, featuring a liquid escapement mechanism. In England,

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