Crematory

A crematory (also known as a crematorium, cremator or retort) is a machine in which people's bodies or remains are burned down to the bones, eliminating all soft tissue. Crematories are usually found in funeral homes, chapels, cemeteries, or in stand-alone facilities. A facility which houses the actual crematory units is referred to as a crematorium.

Prior to the Industrial Revolution, any cremation which took place was on an outdoor, open pyre. With firewood, and to a lesser extent, coal being the only available fuel options and the low energy efficiency inherent in such a configuration, it is no surprise that cremation enjoyed minimal popularity in densely populated areas up until furnace technology developed during the Industrial Revolution could be applied to cremation to make it more practical in an urbanizing world.

The organized movement to reinstate cremation as a viable method for body disposal began in 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 Ludovico Brunetti of Padua published reports or 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, including that of Sir Henry Thompson, 1st Baronet, 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, 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 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.

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