Chris Bishop (2002). The Encyclopedia of Weapons of World War II. Sterling Publishing Company. p.202. ISBN 978-1-58663-762-0. Archived from the original on 2015-03-20 . Retrieved 2016-03-27. The first use in siege warfare was at the 1453 siege of Constantinople by Mehmed the Conqueror. An Italian account of the 1456 siege of Belgrade by Giovanni da Tagliacozzo states that the Ottoman Turks used seven mortars that fired "stone shots one Italian mile high". [6] The time of flight of these was apparently long enough that casualties could be avoided by posting observers to give warning of their trajectories. [7] Engraving depicting the Venetian siege of the Acropolis of Athens, September 1687. The trajectory of the shell that hit the Parthenon, causing its explosion, is marked.

A spigot mortar consists mainly of a solid rod or spigot, onto which a hollow tube in the projectile fits—inverting the normal tube-mortar arrangement. At the top of the tube in the projectile, a cavity contains propellant, such as cordite. There is usually a trigger mechanism built into the base of the spigot, with a long firing pin running up the length of the spigot activating a primer inside the projectile and firing the propellant charge. The advantage of a spigot mortar is that the firing unit (baseplate and spigot) is smaller and lighter than a conventional tube mortar of equivalent payload and range. It is also somewhat simpler to manufacture. Further, most spigot mortars have no barrel in the conventional sense, which means ammunition of almost any weight and diameter can be fired from the same mortar. During the Battle of Iwo Jima, the Imperial Japanese Army used twelve 320 mm mortars against the American forces. Brandt mle 27 (Mortier Brandt de 81 mm modele 27) Infantry Mortar". Militaryfactory.com. Archived from the original on 1 December 2017 . Retrieved 19 November 2017. FR230 may be used to seal apertures in the separating element up to 1100 mm x 1100 mm in a floor or wall (without additionnal reinforcement requirements).Norris, John; Calow, Robert (11 December 2002). Infantry Mortars of World War II. ISBN 9781841764146 . Retrieved June 26, 2012. {{ cite book}}: CS1 maint: multiple names: authors list ( link) [ permanent dead link] Based at Waterloo Lines in Warminster, the SWS comprises two Training Divisions and Training Support Company. A mortar is an artillery weapon which fires explosive shells. The shells are known as (mortar) bombs. They are fired at targets which are close, as mortars do not have long range. It has a short barrel which fires the mortar bomb at a low speed high into the air to reach its target. They have been used since medieval times. Mortars are made in different sizes, from large and heavy mortars to infantry mortars which can be carried by just one soldier. They are called an indirect fire weapon because the bomb drops onto the target from above, rather than being aimed straight at it. Soldiers firing a mortar do not need to be able to see their target.

Ammunition for mortars generally comes in two main varieties: fin-stabilised and spin-stabilised. Examples of the former have short fins on their posterior portion, which control the path of the bomb in flight. Spin-stabilised mortar bombs rotate as they travel along and leave the mortar tube, which stabilises them in much the same way as a rifle bullet. Both types of rounds can be either illumination ( infrared or visible illumination), smoke, high explosive, and training rounds. Mortar bombs are often referred to, incorrectly, as "mortars". [25] Toys". Culturecontent.com. Archived from the original on 10 October 2017 . Retrieved 19 November 2017. Direct Fire Support Division is a part of Specialist Weapons School. The Division comprises three wings that concentrate on running command courses in their different disciplines.Sign up to stay on top of the latest fire safety regulations and specifications, and be one of the first to hear about our latest news and offers. The supporting construction must be classified in accordance with EN 13501-2 for the required fire resistance and be suitable for the imposed load of the FR230. weber fire mortar on kemiallisesti ja keraamisesti sitoutuva kuivalaasti puulämmitteisten tulipesien muuraukseen. Soveltuu tulipesissä käytettävien tulitiilien muuraukseen puilla lämmitettävissä taloustulisijoissa sisätiloissa. Korkein käyttölämpötila +1200 °C. Yhdestä pussista (5 kg) saadaan 2,4 - 2,6 litraa valmista laastia, joka riittää n. 20 tulitiilen muuraukseen. Myyntiyksikkö 5 kg:n pussi (pienin tilausmäärä 3 kpl = keräyslaatikko) tai 15 kg:n säkki.

From the 18th to the early 20th century, very heavy siege mortars were used. These were very difficult to move around. These had up to one metre calibre. They were often made of cast iron. Smaller designs that were easier to move around were brought in during the First World War. Mortars are still used today. Largest Mortar". Guinness World Records. Archived from the original on 2006-02-10 . Retrieved 2006-04-04. Chisholm, Hugh, ed. (1911). "Coehoorn, Menno, Baron van". Encyclopædia Britannica. Vol.8 (11thed.). Cambridge University Press. p.40.

Why Does Fire Cement Crack?

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