Latent heat (also known as latent energy or heat of transformation ) is energy released or absorbed, by a body or a thermodynamic system , during a constant-temperature process—usually a first-order phase transition , like melting or condensation.
99-421: A crematorium or crematory is a venue for the cremation of the dead . Modern crematoria contain at least one cremator (also known as a crematory , retort or cremation chamber ), a purpose-built furnace. In some countries a crematorium can also be a venue for open-air cremation . In many countries, crematoria contain facilities for funeral ceremonies, such as a chapel . Some crematoria also incorporate
198-551: A columbarium , a place for interring cremation ashes. Prior to the Industrial Revolution , cremation could only take place on an outdoor, open pyre; the alternative was burial . In the 19th century, the development of new furnace technology and contact with cultures that practiced cremation led to its reintroduction in the Western world . The organized movement to instate cremation as a viable method for body disposal began in
297-565: A body is heated at constant temperature by thermal radiation in a microwave field for example, it may expand by an amount described by its latent heat with respect to volume or latent heat of expansion , or increase its pressure by an amount described by its latent heat with respect to pressure . Latent heat is energy released or absorbed by a body or a thermodynamic system during a constant-temperature process. Two common forms of latent heat are latent heat of fusion ( melting ) and latent heat of vaporization ( boiling ). These names describe
396-418: A coffin or a combustible container. This allows the body to be quickly and safely slid into the cremator. It also reduces health risks to the operators. The coffin or container is inserted (charged) into the cremator as quickly as possible to avoid heat loss. Some crematoria allow relatives to view the charging. This is sometimes done for religious reasons, such as in traditional Hindu and Jain funerals, and
495-623: A constant 47 °F (8 °C). The water had therefore received 40 – 33 = 7 “degrees of heat”. The ice had been heated for 21 times longer and had therefore received 7 × 21 = 147 “degrees of heat”. The temperature of the ice had increased by 8 °F. The ice now stored, as it were, an additional 8 “degrees of heat” in a form which Black called sensible heat , manifested as temperature, which could be felt and measured. 147 – 8 = 139 “degrees of heat” were, so to speak, stored as latent heat , not manifesting itself. (In modern thermodynamics
594-411: A cremation can vary from 70 minutes to 210 minutes. Cremators used to run on timers (some still do) and one would have to determine the weight of the body therefore calculating how long the body has to be cremated for and set the timers accordingly. Other types of crematories merely have a start and a stop function for the cremation displayed on the user interface. The end of the cremation must be judged by
693-524: A cremator, which is located at a crematorium or crematory . In many countries, the crematorium is a venue for funerals as well as cremation. A cremator is an industrial furnace that is able to generate temperatures of 871–982 °C (1,600–1,800 °F) to ensure the disintegration of the corpse. Modern cremator fuels include oil , natural gas , propane , and, in Hong Kong, coal gas . Modern cremators automatically monitor their interior to tell when
792-461: A growing concern. 900 °C (1,650 °F) The application of computer control has allowed cremators to be more automated, in that temperature and oxygen sensors within the unit along with pre-programmed algorithms based upon the weight of the deceased allow the unit to operate with less user intervention. Such computer systems may also streamline recordkeeping requirements for tracking, environmental, and maintenance purposes. The time to carry out
891-546: A half the bodies are completely burned. This corresponds to a daily capacity of about 2,000 bodies... Crematoria III and IV work on nearly the same principle, but their capacity is only half as large. Thus the total capacity of the four cremating and gassing plants at B IRKENAU amounts to about 6,000 daily. The Holocaust furnaces were supplied by a number of manufacturers, with the best known and most common being Topf and Sons as well as Kori Company of Berlin, whose ovens were elongated to accommodate two bodies, slid inside from
990-513: A health risk and may be buried, interred in a memorial site, retained by relatives or scattered in various ways. Cremation dates from at least 17,000 years ago in the archaeological record, with the Mungo Lady , the remains of a partly cremated body found at Lake Mungo , Australia. Alternative death rituals which emphasize one method of disposal – burial , cremation, or exposure – have gone through periods of preference throughout history. In
1089-405: A liquid during its freezing; again, much more than could be explained by the decrease of its temperature alone. Black would compare the change in temperature of two identical quantities of water, heated by identical means, one of which was, say, melted from ice, whereas the other was heated from merely cold liquid state. By comparing the resulting temperatures, he could conclude that, for instance,
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#17330927128401188-454: A liquid on a surface, then the vapor's latent energy absorbed during evaporation is released as the liquid's sensible heat onto the surface. The large value of the enthalpy of condensation of water vapor is the reason that steam is a far more effective heating medium than boiling water, and is more hazardous. In meteorology , latent heat flux is the flux of energy from the Earth's surface to
1287-567: A long debate about the merits and demerits of cremation. Laws against cremation were challenged and invalidated in 1915 (two years after the construction of the first crematorium in the Netherlands), though cremation did not become legally recognised until 1955. During World War II (1939–45), Nazi Germany used specially built furnaces in at least six extermination camps throughout occupied Poland including at Auschwitz-Birkenau , Chełmno , Belzec , Majdanek , Sobibor and Treblinka , where
1386-422: A man to death on a warm summer's day." The English word latent comes from Latin latēns , meaning lying hidden . The term latent heat was introduced into calorimetry around 1750 by Joseph Black , commissioned by producers of Scotch whisky in search of ideal quantities of fuel and water for their distilling process to study system changes, such as of volume and pressure, when the thermodynamic system
1485-439: A plain, particle-board coffin (known in the trade as a "chippie", "shipper" or "pyro") can be used. Handles (if fitted) are plastic and approved for use in a cremator. Cremations can be "delivery only", with no preceding chapel service at the crematorium (although a church service may have been held) or preceded by a service in one of the crematorium chapels. Delivery-only allows crematoria to schedule cremations to make best use of
1584-411: A resultant temperature change in a body. The terms sensible heat and latent heat refer to energy transferred between a body and its surroundings, defined by the occurrence or non-occurrence of temperature change; they depend on the properties of the body. Sensible heat is sensed or felt in a process as a change in the body's temperature. Latent heat is energy transferred in a process without change of
1683-410: A thick watertight polyethylene plastic bag contained within a hard snap-top rectangular plastic container , which is labeled with a printed paper label. The basic sealed plastic container bag may be contained within a further cardboard box or velvet sack, or they may be contained within an urn if the family had already purchased one. An official certificate of cremation prepared under the authority of
1782-601: A well-known figure in literary and scientific circles. By the end of the year, the Cremation Society of Great Britain had overseen 2 more cremations, a total of 3 out of 597,357 deaths in the UK that year. In 1888, 28 cremations took place at the venue. In 1891, Woking Crematorium added a chapel, pioneering the concept of a crematorium being a venue for funerals as well as cremation. Other early crematoria in Europe were built in 1878 in
1881-512: Is also customary in Japan . In the United States federal law does not dictate any container requirements for cremation. Certain states require an opaque or non-transparent container for all cremations. This can be a simple corrugated cardboard box or a wooden casket ( coffin ). Another option is a cardboard box that fits inside a wooden shell, which is designed to look like a traditional casket. After
1980-506: Is an ancient tradition. Starting in the 19th century, cremation was introduced or reintroduced into other parts of the world. In modern times, cremation is commonly carried out with a closed furnace (cremator) , at a crematorium. Cremation leaves behind an average of 2.4 kg (5.3 lb) of remains known as ashes or cremains . This is not all ash but includes unburnt fragments of bone mineral, which are commonly ground into powder. They are inorganic and inert, and thus do not constitute
2079-452: Is approximately equivalent to 3 m (105 ft) of natural gas, or 3 liters of fuel oil (0.8 US gallons). Additional energy is necessary to make up for the heat capacity ("preheating") of the furnace, fuel burned for emissions control, and heat losses through the insulation and in the flue gases. As a result, crematories are most often heated by burners fueled by natural gas . LPG (propane/butane) or fuel oil may be used where natural gas
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#17330927128402178-601: Is first attested in the Cemetery H culture (from c. 1900 BCE), considered the last phase of Indus Valley Civilisation and beginning of the Vedic civilization . The Rigveda contains a reference to the emerging practice, in RV 10 .15.14, where the forefathers "both cremated ( agnidagdhá- ) and uncremated ( ánagnidagdha- )" are invoked. Cremation remained common but not universal, in both ancient Greece and ancient Rome. According to Cicero, burial
2277-516: Is not available. These burners can range in power from 150 to 400 kilowatts (0.51 to 1.4 million British thermal units per hour). Crematories heated by electricity also exist in India, where electric heating elements bring about cremation without the direct application of flame to the body. Coal, coke , and wood were used in the past, heating the chambers from below (like a cooking pot). This resulted in an indirect heat and prevented mixing of ash from
2376-434: Is sealed, for this reason. When cremation is finished, the remains are passed through a magnetic field to remove any metal, which will be interred elsewhere in the crematorium grounds or, increasingly, recycled. The ashes are entered into a cremulator to further grind the remains down into a finer texture before being given to relatives or loved ones or scattered in the crematorium grounds where facilities exist. In Germany,
2475-615: Is that "cremains" is thought to have less connection with the deceased, whereas a loved one's "cremated remains" has a more identifiable human connection. ) After final grinding, the ashes are placed in a container, which can be anything from a simple cardboard box to a decorative urn . The default container used by most crematoria, when nothing more expensive has been selected, is usually a hinged, snap-locking plastic box. Cremated remains are mostly dry calcium phosphates with some minor minerals, such as salts of sodium and potassium. Sulfur and most carbon are driven off as oxidized gases during
2574-427: Is usually simply an insulation material, e.g. , mineral wool . Inside is typically a layer of insulation brick, mostly calcium silicate in nature. Heavy duty cremators are usually designed with two layers of fire bricks inside the insulation layer. The layer of fire bricks in contact with the combustion process protects the outer layer and must be replaced from time to time. The body is generally required to be inside
2673-706: The Cremation Society of Great Britain in 1874." They founded the United Kingdom's first crematorium in Woking , with Gorini travelling to England to assist the installation of a cremator. They first tested it on 17 March 1879 with the body of a horse. After protests and an intervention by the Home Secretary , Sir Richard Cross , their plans were put on hold. In 1884, the Welsh Neo-Druidic priest William Price
2772-628: The Cycladic civilization in 3000 BCE until the Sub- Mycenaean era in 1200–1100 BCE, Greeks practiced burial. Cremation appeared around the 12th century BCE, probably influenced by Anatolia . Until the Christian era, when inhumation again became the only burial practice, both combustion and inhumation had been practiced, depending on the era and location. In Rome's earliest history, both inhumation and cremation were in common use among all classes. Around
2871-573: The Urnfield culture (from c. 1300 BCE). In the Iron Age , inhumation again becomes more common, but cremation persisted in the Villanovan culture and elsewhere. Homer 's account of Patroclus ' burial describes cremation with subsequent burial in a tumulus , similar to Urnfield burials, and qualifying as the earliest description of cremation rites. This may be an anachronism, as during Mycenaean times burial
2970-779: The West Terrace Cemetery in the South Australian capital of Adelaide in 1901. This small building, resembling the buildings at Woking , remained largely unchanged from its 19th-century style and was in full operation until the late 1950s. The oldest operating crematorium in Australia is at Rookwood Cemetery , in Sydney . It opened in 1925. In the Netherlands, the foundation of the Association for Optional Cremation in 1874 ushered in
3069-575: The World War II with the " final solutions to the Jewish question ", crematoria were widely used for the disposal of corpses. The most technically advanced cremation ovens were those developed by the company “ Topf and Sons ” from Erfurt . While a crematorium can be any place containing a cremator, modern crematoria are designed to serve a number of purposes. As well as being a place for the practical but dignified disposal of dead bodies, they must also serve
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3168-446: The atmosphere that is associated with evaporation or transpiration of water at the surface and subsequent condensation of water vapor in the troposphere . It is an important component of Earth's surface energy budget. Latent heat flux has been commonly measured with the Bowen ratio technique, or more recently since the mid-1900s by the eddy covariance method. In 1748, an account
3267-405: The latent heat of vaporization (liquid to gas) and the latent heat of sublimation (solid to gas). The term was introduced around 1762 by Scottish chemist Joseph Black . Black used the term in the context of calorimetry where a heat transfer caused a volume change in a body while its temperature was constant. In contrast to latent heat, sensible heat is energy transferred as heat , with
3366-623: The 1850s. His furnace operated at a high temperature by using regenerative preheating of fuel and air for combustion . In regenerative preheating, the exhaust gases from the furnace are pumped into a chamber containing bricks, where heat is transferred from the gases to the bricks. The flow of the furnace is then reversed so that fuel and air pass through the chamber and are heated by the bricks. Through this method, an open-hearth furnace can reach temperatures high enough to melt steel, and this process made cremation an efficient and practical proposal. Charles's nephew, Carl Friedrich von Siemens perfected
3465-472: The 1870s. In 1869 the idea was presented to the Medical International Congress of Florence by Professors Coletti and Castiglioni "in the name of public health and civilization". In 1873, Professor Paolo Gorini of Lodi and Professor Lodovico Brunetti of Padua published reports or practical work they had conducted. A model of Brunetti's cremating apparatus, together with the resulting ashes,
3564-409: The 7th century, when Christian burial became general. In parts of Europe, cremation was forbidden by law, and even punishable by death if combined with Heathen rites. Cremation was sometimes used by Catholic authorities as part of punishment for accused heretics, which included burning at the stake . For example, the body of John Wycliff was exhumed years after his death and burned to ashes, with
3663-526: The Cremulator used. The mean weight of an adult's remains is 2.4 kg (5.3 lb); the mean weight for adult males is about 1 kg (2.2 lb) higher than that for adult females. There are various types of Cremulators, including rotating devices, grinders, and older models using heavy metal balls. The grinding process typically takes about 20 seconds. In most Asian countries, the bones are not pulverised, unless requested beforehand. When not pulverised,
3762-558: The Middle East and Europe, both burial and cremation are evident in the archaeological record in the Neolithic era. Cultural groups had their own preferences and prohibitions. The ancient Egyptians developed an intricate transmigration-of-soul theology, which prohibited cremation. This was also widely adopted by Semitic peoples. The Babylonians, according to Herodotus , embalmed their dead. Phoenicians practiced both cremation and burial. From
3861-500: The United Kingdom and the Netherlands. Starting in the 1960s, cremation has become more common than burial in several countries where the latter is traditional. This has included the United Kingdom (1968), Czechoslovakia (1980), Canada (early 2000s), the United States (2016) and Finland (2017). Factors cited include cheaper costs (especially a factor after the 2008 recession ), growth in secular attitudes and declining opposition in some Christian denominations. The cremation occurs in
3960-559: The West opened in Milan in 1876. By the end of the 19th century, several countries had seen their first crematorium open. Golders Green Crematorium was built from 1901 to 1928 in London and pioneered two features that would become common in future crematoria: the separation of entrance and exit, and a garden of remembrance. In the extermination camps created by the authorities of Nazi Germany during
4059-731: The Western World opened in Milan in 1876. Milan's "Crematorium Temple" was built in the Monumental Cemetery . The building still stands but ceased to be operational in 1992. Sir Henry Thompson, 1st Baronet , a surgeon and Physician to the Queen Victoria , had seen Gorini's cremator at the Vienna Exhibition and had returned home to become the first and chief promoter of cremation in England. His main reason for supporting cremation
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4158-569: The ashes thrown in a river, explicitly as a posthumous punishment for his denial of the Roman Catholic doctrine of transubstantiation . The first to advocate for the use of cremation was the physician Sir Thomas Browne in Urne Buriall (1658) which interpreted cremation as means of oblivion and reveals plainly that "'there is no antidote against the Opium of time...". Honoretta Brooks Pratt became
4257-447: The atmosphere or ocean, or ice, without those phase changes, though it is associated with changes of pressure and volume. The original usage of the term, as introduced by Black, was applied to systems that were intentionally held at constant temperature. Such usage referred to latent heat of expansion and several other related latent heats. These latent heats are defined independently of the conceptual framework of thermodynamics. When
4356-532: The back side. The ashes were taken out from the front side. In the 20th century, cremation gained varying degrees of acceptance in most Christian denominations. William Temple , the most senior bishop in the Church of England , was cremated after his death in office in 1944. The Roman Catholic Church accepted the practice more slowly. In 1963, at the Second Vatican Council Pope Paul VI lifted
4455-412: The ball of a mercury thermometer with ether and using bellows to evaporate the ether. With each subsequent evaporation , the thermometer read a lower temperature, eventually reaching 7 °F (−14 °C). Another thermometer showed that the room temperature was constant at 65 °F (18 °C). In his letter Cooling by Evaporation , Franklin noted that, "One may see the possibility of freezing
4554-418: The ban on cremation, and in 1966 allowed Catholic priests to officiate at cremation ceremonies. This is done on the condition that the ashes must be buried or interred, not scattered. Many countries where burial is traditional saw cremation rise to become a significant, if not the most common way of disposing of a dead body. In the 1960s and 1970s, there was an unprecedented phase of crematorium construction in
4653-454: The bodies of those murdered by gassing were disposed of using incineration. The efficiency of industrialised killing of Operation Reinhard during the most deadly phase of the Holocaust produced too many corpses, therefore the crematoria manufactured to SS specifications were put into use in all of them to handle the disposals around the clock, day and night. The Vrba–Wetzler report offers
4752-504: The body – one at a time usually contained in some type of combustible casket or container. This chamber has at least one burner to provide the heat which vaporizes the water content of the body and aids in combustion of the organic portion. A large door exists to load the body container. Temperature in the primary chamber is typically between 760–980 °C (1,400–1,800 °F). Higher temperatures speed cremation but consume more energy, generate more nitric oxide , and accelerate spalling of
4851-402: The body's temperature, for example, in a phase change (solid/liquid/gas). Both sensible and latent heats are observed in many processes of transfer of energy in nature. Latent heat is associated with the change of phase of atmospheric or ocean water, vaporization , condensation , freezing or melting , whereas sensible heat is energy transferred that is evident in change of the temperature of
4950-431: The bones are collected by the family and stored as one might do with ashes. The appearance of cremated remains after grinding is one of the reasons they are called ashes , although a non-technical term sometimes used is "cremains", a portmanteau of "cremated" and "remains". (The Cremation Association of North America prefers that the word "cremains" not be used for referring to "human cremated remains". The reason given
5049-564: The burning. That custom was also very widespread among the Germanic peoples of the northern continental lands from which the Anglo-Saxon migrants are supposed to have been derived, during the same period. These ashes were usually thereafter deposited in a vessel of clay or bronze in an "urn cemetery". The custom again died out with the Christian conversion of the Anglo-Saxons or Early English during
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#17330927128405148-543: The coffin descend into a grave, they incorporate a mechanism for removing the coffin from sight. On the other hand, in Japan, mourners will watch the coffin enter the cremator, then will return after the cremation for the custom of picking the bones from the ashes. While open outdoor pyres were used in the past and are often still used in many areas of the world today, notably India, most cremation in industrialized nations takes place within enclosed furnaces designed to maximize use of
5247-407: The coffin once it has arrived at the crematorium, and rules stipulate that it must be cremated within 72 hours of the funeral service. Therefore, in the United Kingdom, bodies are cremated in the same coffin that they are placed in at the undertaker's, although the regulations allow the use of an approved "cover" during the funeral service. It is recommended that jewellery be removed before the coffin
5346-458: The cooling water required). In 1762, Black announced the following research and results to a society of professors at the University of Glasgow. Black had placed equal masses of ice at 32 °F (0 °C) and water at 33 °F (0.6 °C) respectively in two identical, well separated containers. The water and the ice were both evenly heated to 40 °F by the air in the room, which was at
5445-408: The cremation process is complete and have a spyhole so that an operator can see inside. The time required for cremation varies from body to body, with the average being 90 minutes for an adult body. The chamber where the body is placed is called a cremation chamber or retort and is lined with heat-resistant refractory bricks. Refractory bricks are designed in several layers. The outermost layer
5544-399: The crematorium accompanies the remains, and if required by law, the permit for disposition of human remains, which must remain with the cremated remains. Latent heat Latent heat can be understood as hidden energy which is supplied or extracted to change the state of a substance without changing its temperature or pressure. This includes the latent heat of fusion (solid to liquid),
5643-444: The cremators, perhaps by holding the body overnight in a refrigerator, allowing a lower fee to be charged. The box containing the body is placed in the retort and incinerated at a temperature of 760 to 1,150 °C (1,400 to 2,100 °F). During the cremation process, the greater portion of the body (especially the organs and other soft tissues) is vaporized and oxidized by the intense heat; gases released are discharged through
5742-415: The direction of energy flow when changing from one phase to the next: from solid to liquid, and liquid to gas. In both cases the change is endothermic , meaning that the system absorbs energy. For example, when water evaporates, an input of energy is required for the water molecules to overcome the forces of attraction between them and make the transition from water to vapor. If the vapor then condenses to
5841-419: The emotional and spiritual needs of the mourners. The design of a crematorium is often heavily influenced by the funeral customs of its country. For example, crematoria in the United Kingdom are designed with a separation between the funeral and cremation facilities, as it is not customary for mourners to witness the coffin being placed in the cremator. To provide a substitute for the traditional ritual of seeing
5940-512: The energy of interaction in a given configuration of particles, i.e. a form of potential energy , and the sensible heat as an energy that was indicated by the thermometer, relating the latter to thermal energy . A specific latent heat ( L ) expresses the amount of energy in the form of heat ( Q ) required to completely effect a phase change of a unit of mass ( m ), usually 1 kg , of a substance as an intensive property : Intensive properties are material characteristics and are not dependent on
6039-474: The exhaust gases from the furnace are pumped into a chamber containing bricks, where heat is transferred from the gases to the bricks. The flow of the furnace is then reversed so that fuel and air pass through the chamber and are heated by the bricks. Through this method, an open-hearth furnace can reach temperatures high enough to melt steel , and this process made cremation an efficient and practical proposal. Charles's nephew, Carl Friedrich von Siemens perfected
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#17330927128406138-438: The exhaust system. Jewelry, such as necklaces, wrist-watches and rings, are ordinarily removed before cremation, and returned to the family. Several implanted devices are required to be removed. Pacemakers and other medical devices can cause large, dangerous explosions. Contrary to popular belief, the cremated remains are not ashes in the usual sense. After the incineration is completed, the dry bone fragments are swept out of
6237-456: The first recorded cremated European individual in modern times when she died on 26 September 1769 and was illegally cremated at the burial ground on Hanover Square in London . In Europe, a movement to reintroduce cremation as a viable method for body disposal began in the 1870s. This was made possible by the invention of new furnace technology and contact with eastern cultures that practiced it. At
6336-457: The following description. At present there are four crematoria in operation at B IRKENAU , two large ones, I and II, and two smaller ones, III and IV. Those of type I and II consist of 3 parts, i.e.,: (A) the furnace room; (B) the large halls; and (C) the gas chamber. A huge chimney rises from the furnace room around which are grouped nine furnaces, each having four openings. Each opening can take three normal corpses at once and after an hour and
6435-401: The fuel with ash from the body. The term retort when applied to cremation furnaces originally referred to this design. There has been interest, mainly in developing nations, to develop a cremator heated by concentrated solar energy . Another new design starting to find use in India, where wood is traditionally used for cremation, is a cremator based around a wood gas fired process. Due to
6534-410: The funeral service, the box is removed from the shell before cremation, permitting the shell to be re-used. In the United Kingdom, the body is not removed from the coffin and is not placed into a container as described above. The body is cremated with the coffin which is why all British coffins that are to be used for cremation must be combustible. The Code of Cremation Practice forbids the opening of
6633-433: The furnace's refractory lining. The secondary chamber may be at the rear or above the primary chamber. A secondary burner(s) fires into this chamber, oxidizing any organic material which passes from the primary chamber. This acts as a method of pollution control to eliminate the emission of odors and smoke. The secondary chamber typically operates at a temperature greater than 900 °C (1,650 °F). The flue gases from
6732-407: The general view at that time was that melting was inevitably accompanied by a small increase in temperature, and that no more heat was required than what the increase in temperature would require in itself. Soon, however, Black was able to show that much more heat was required during melting than could be explained by the increase in temperature alone. He was also able to show that heat is released by
6831-434: The idea of heat contained has been abandoned, so sensible heat and latent heat have been redefined. They do not reside anywhere.) Black next showed that a water temperature of 176 °F was needed to melt an equal mass of ice until it was all 32 °F. So now 176 – 32 = 144 “degrees of heat” seemed to be needed to melt the ice. The modern value for the heat of fusion of ice would be 143 “degrees of heat” on
6930-428: The manner in which the wood gas is produced, such crematories use only a fraction of the required wood; and according to multiple sources, have far less impact on the environment than traditional natural gas or fuel oil processes. A typical unit contains a primary and secondary combustion chamber. These chambers are lined with a refractory brick designed to withstand the high temperatures. The primary chamber contains
7029-607: The mid-Republic, inhumation was almost exclusively replaced by cremation, with some notable exceptions, and remained the most common funerary practice until the middle of the Empire, when it was almost entirely replaced by inhumation. In Europe, there are traces of cremation dating to the Early Bronze Age (c. 2000 BCE) in the Pannonian Plain and along the middle Danube . The custom became dominant throughout Bronze Age Europe with
7128-423: The operator who in turn stops the cremation process. As an energy-saving measure, some cremators provide heating for the building. Cremation Cremation is a method of final disposition of a dead body through burning . Cremation may serve as a funeral or post-funeral rite and as an alternative to burial . In some countries, including India , Nepal , and Syria , cremation on an open-air pyre
7227-439: The process is mostly similar to that of the United Kingdom. The body is cremated in the coffin. A piece of fire clay with a number on it is used for identifying the remains of the dead body after burning. The remains are then placed in a container called an ash capsule , which generally is put into a cinerary urn. In Australia, reusable or cardboard coffins are rare, with only a few manufacturers now supplying them. For low cost,
7326-421: The process, although about 1–4% of carbon remains as carbonate. The ash remaining represents very roughly 3.5% of the body's original mass (2.5% in children). Because the weight of dry bone fragments is so closely connected to skeletal mass, their weight varies greatly from person to person. Because many changes in body composition (such as fat and muscle loss or gain) do not affect the weight of cremated remains,
7425-544: The public. 760–980 °C (1,400–1,800 °F) . In addition, filtration systems ( baghouses ) are being applied to crematories in many countries. Activated carbon adsorption is being considered for mercury abatement (as a result of dental amalgam ). Much of this technology is borrowed from the waste incineration industry on a scaled-down basis. With the rise in the use of cremation in Western nations where amalgam has been used liberally in dental restorations, mercury has been
7524-447: The remains are processed, smaller bits of metal such as tooth fillings, and rings (commonly known as gleanings ) are sieved out and may be later interred in common, consecrated ground in a remote area of the cemetery. They may also be sold as precious metal scrap. Cremated remains are returned to the next of kin in different manners according to custom and country. In the United States, the cremated remains are almost always contained in
7623-404: The retort and pulverised by a machine called a Cremulator —essentially a high-capacity, high-speed Pulverizer —to process them into "ashes" or "cremated remains", although pulverisation may also be performed by hand. This leaves the bone with a fine sand like texture and color, able to be scattered without need for mixing with any foreign matter, though the size of the grain varies depending on
7722-474: The risk of explosion. Large items such as titanium hip replacements (which tarnish but do not melt) or casket hinges are usually removed before processing, as they may damage the processor. (If they are missed at first, they must ultimately be removed before processing is complete, as items such as titanium joint replacements are far too durable to be ground.) Implants may be returned to the family, but are more commonly sold as ferrous/non-ferrous scrap metal . After
7821-444: The same scale (79.5 “degrees of heat Celsius”). Finally Black increased the temperature of and vaporized respectively two equal masses of water through even heating. He showed that 830 “degrees of heat” was needed for the vaporization; again based on the time required. The modern value for the heat of vaporization of water would be 967 “degrees of heat” on the same scale. Later, James Prescott Joule characterised latent energy as
7920-413: The secondary chamber are usually vented to the atmosphere through a refractory-lined flue. They are at a very high temperature, and interest in recovering this thermal energy e.g. for space heating of the funeral chapel, or other facilities or for distribution into local district heating networks has arisen in recent years. Such heat recovery efforts have been viewed in both a positive and negative light by
8019-483: The size or extent of the sample. Commonly quoted and tabulated in the literature are the specific latent heat of fusion and the specific latent heat of vaporization for many substances. From this definition, the latent heat for a given mass of a substance is calculated by where: The following table shows the specific latent heats and change of phase temperatures (at standard pressure) of some common fluids and gases. The specific latent heat of condensation of water in
8118-435: The temperature of the sample melted from ice was 140 °F lower than the other sample, thus melting the ice absorbed 140 "degrees of heat" that could not be measured by the thermometer, yet needed to be supplied, thus it was "latent" (hidden). Black also deduced that as much latent heat as was supplied into boiling the distillate (thus giving the quantity of fuel needed) also had to be absorbed to condense it again (thus giving
8217-405: The temperature range from −25 °C to 40 °C is approximated by the following empirical cubic function: where the temperature T {\displaystyle T} is taken to be the numerical value in °C. For sublimation and deposition from and into ice, the specific latent heat is almost constant in the temperature range from −40 °C to 0 °C and can be approximated by
8316-503: The thermal energy consumed while minimizing the emission of smoke and odors. Video for example-how a crematorium works A human body usually contains a negative caloric value, meaning that energy is required to combust it. This is a result of the high water content; all water must be vaporized which requires a very large amount of thermal energy . A 68 kg (150 lbs) body which contains 65% water will require 100 MJ of thermal energy before any combustion will take place. 100 MJ
8415-455: The time, many proponents believed in the miasma theory , and that cremation would reduce the "bad air" that caused diseases. These movements were associated with secularism and gained a following in cultural and intellectual circles. In Italy, the movement was associated with anti-clericalism and Freemasonry , whereas these were not major themes of the movement in Britain. In 1869, the idea
8514-798: The town of Gotha in Germany and later in Heidelberg in 1891. The first modern crematory in the U.S. was built in 1876 by Francis Julius LeMoyne after hearing about its use in Europe. Like many early proponents, he was motivated by a belief it would be beneficial for public health. Before LeMoyne's crematory closed in 1901, it had performed 42 cremations. Other countries that opened their first crematorium included Sweden (1887 in Stockholm), Switzerland (1889 in Zurich) and France (1889 in Père Lachaise , Paris). Some of
8613-492: The use of this furnace for the incineration of organic material at his factory in Dresden . The radical politician, Sir Charles Wentworth Dilke , took the corpse of his dead wife there to be cremated in 1874. The efficient and cheap process brought about the quick and complete incineration of the body and was a fundamental technical breakthrough that finally made industrial cremation a practical possibility. The first crematorium in
8712-442: The use of this furnace for the incineration of organic material at his factory in Dresden . The radical politician, Sir Charles Wentworth Dilke , took the corpse of his dead wife there to be cremated in 1874. The efficient and cheap process brought about the quick and complete incineration of the body and was a fundamental technical breakthrough that finally made industrial cremation a practical possibility. The first crematorium in
8811-472: The various Protestant churches came to accept cremation. In Anglican and Nordic Protestant countries, cremation gained acceptance (though it did not yet become the norm) first by the upper classes and cultural circles, and then by the rest of the population. In 1905, Westminster Abbey interred ashes for the first time; by 1911 the Abbey was expressing a preference for interring ashes. The 1908 Catholic Encyclopedia
8910-786: The weight of the remains can be more closely predicted from the person's height and sex (which predicts skeletal weight), than it can be predicted from the person's simple weight. Ashes of adults can be said to weigh from 876 to 3,784 g (1 lb 15 oz to 8 lb 5 oz), with women's ashes generally weighing below 2,750 g (6 lb 1 oz) and men's ashes generally weighing above 1,887 g (4 lb 3 oz). Bones are not all that remain after cremation. There may be melted metal lumps from missed jewellery; casket furniture; dental fillings; and surgical implants, such as hip replacements. Breast implants do not have to be removed before cremation. Some medical devices such as pacemakers may need to be removed before cremation to avoid
9009-458: Was arrested and put on trial for attempting to cremate his son's body. Price successfully argued in court that while the law did not state that cremation was legal, it also did not state that it was illegal. The case set a precedent that allowed the Cremation Society to proceed. In 1885, the first official cremation in the United Kingdom took place in Woking. The deceased was Jeanette Pickersgill ,
9108-480: Was considered the more archaic rite in Rome. The rise of Christianity saw an end to cremation in Europe, though it may have already been in decline. In early Roman Britain , cremation was usual but diminished by the 4th century. It then reappeared in the 5th and 6th centuries during the migration era, when sacrificed animals were sometimes included on the pyre, and the dead were dressed in costume and with ornaments for
9207-787: Was critical of the development, referring to them as a "sinister movement" and associating them with Freemasonry , although it said that "there is nothing directly opposed to any dogma of the Church in the practice of cremation." In the U.S. only about one crematory per year was built in the late 19th century. As embalming became more widely accepted and used, crematories lost their sanitary edge. Not to be left behind, crematories had an idea of making cremation beautiful. They started building crematories with stained-glass windows and marble floors with frescoed walls. Australia also started to establish modern cremation movements and societies. Australians had their first purpose-built modern crematorium and chapel in
9306-551: Was exhibited at the Vienna Exposition in 1873 and attracted great attention, including that of Sir Henry Thompson , a surgeon and Physician to the Queen Victoria , who "returned home to become the first and chief promoter of cremation in England". Meanwhile, Sir Charles William Siemens had developed his regenerative furnace in the 1850s. His furnace operated at a high temperature by using regenerative preheating of fuel and air for combustion . In regenerative preheating,
9405-469: Was generally preferred, and Homer may have been reflecting the more common use of cremation at the time the Iliad was written, centuries later. Criticism of burial rites is a common aspersion by competing religions and cultures, including the association of cremation with fire sacrifice or human sacrifice . Hinduism and Jainism are notable for not only allowing but prescribing cremation. Cremation in India
9504-413: Was held at constant temperature in a thermal bath. It was known that when the air temperature rises above freezing—air then becoming the obvious heat source—snow melts very slowly and the temperature of the melted snow is close to its freezing point. In 1757, Black started to investigate if heat, therefore, was required for the melting of a solid, independent of any rise in temperature. As far Black knew,
9603-537: Was presented to the Medical International Congress of Florence by Professors Coletti and Castiglioni "in the name of public health and civilization". In 1873, Professor Paolo Gorini of Lodi and Professor Ludovico Brunetti of Padua published reports of practical work they had conducted. A model of Brunetti's cremating apparatus, together with the resulting ashes, was exhibited at the Vienna Exposition in 1873 and attracted great attention Meanwhile, Sir Charles William Siemens had developed his regenerative furnace in
9702-676: Was published in The Edinburgh Physical and Literary Essays of an experiment by the Scottish physician and chemist William Cullen . Cullen had used an air pump to lower the pressure in a container with diethyl ether . No heat was withdrawn from the ether, yet the ether boiled, but its temperature decreased. And in 1758, on a warm day in Cambridge , England, Benjamin Franklin and fellow scientist John Hadley experimented by continually wetting
9801-432: Was that "it was becoming a necessary sanitary precaution against the propagation of disease among a population daily growing larger in relation to the area it occupied". In addition, he believed, cremation would prevent premature burial, reduce the expense of funerals, spare mourners the necessity of standing exposed to the weather during interment, and urns would be safe from vandalism. He joined with other proponents to form
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