Question: When was the man that Dewar benzene is named for born?

full_context: Document 1: Peter Desaga: Peter Desaga was a German instrument maker at the University of Heidelberg who worked with Robert Wilhelm Bunsen. In 1855, Desaga perfected an earlier design of the laboratory burner by Michael Faraday into the Bunsen burner. The Desaga family held the right to market the burner for generations, as part of an agreement made with Bunsen. The Bunsen burner was essential to the invention of the spectroscope by Robert Wilhelm Bunsen and Gustav Robert Georg Kirchhoff.
Document 2: Cryogenic storage dewar: A cryogenic storage dewar (named after James Dewar) is a specialised type of vacuum flask used for storing cryogens (such as liquid nitrogen or liquid helium), whose boiling points are much lower than room temperature. Cryogenic storage dewars may take several different forms including open buckets, flasks with loose-fitting stoppers and self-pressurising tanks. All dewars have walls constructed from two or more layers, with a high vacuum maintained between the layers. This provides very good thermal insulation between the interior and exterior of the dewar, which reduces the rate at which the contents boil away. Precautions are taken in the design of dewars to safely manage the gas which is released as the liquid slowly boils. The simplest dewars allow the gas to escape either through an open top or past a loose-fitting stopper to prevent the risk of explosion. More sophisticated dewars trap the gas above the liquid, and hold it at high pressure. This increases the boiling point of the liquid, allowing it to be stored for extended periods. Excessive vapour pressure is released automatically through safety valves. The method of decanting liquid from a dewar depends upon its design. Simple dewars may be tilted, to pour liquid from the neck. Self-pressurising designs use the gas pressure in the top of the dewar to force the liquid upward through a pipe leading to the neck.
Document 3: Butalene: Butalene is a polycyclic hydrocarbon composed of two fused cyclobutadiene rings. A reported possible synthesis of it involves an elimination reaction from a Dewar benzene derivative. The structure itself can be envisioned as benzene with an internal bridge, and calculations indicate it is somewhat less stable than the open 1,4-didehydrobenzene biradical, the valence isomer in which that bridged bond is broken.
Document 4: Benzene: Benzene is an important organic chemical compound with the chemical formula CH. The benzene molecule is composed of 6 carbon atoms joined in a ring with 1 hydrogen atom attached to each. As it contains only carbon and hydrogen atoms, benzene is classed as a hydrocarbon.
Document 5: Mount Dewar: Mount Dewar ( ) is a mountain rising to about 1,600 m to the southwest of Aronson Corner in the Pioneers Escarpment, Shackleton Range. It was photographed from the air by the U.S. Navy in 1967 and surveyed by the British Antarctic Survey from 1968–71. In association with the names of pioneers of polar life and travel grouped in this area, it was named in 1971 by the UK Antarctic Place-Names Committee after Sir James Dewar, a Scottish chemist and physicist who invented the thermos flask about 1892.
Document 6: Cycloundecane: Cycloundecane is a saturated cyclic organic compound with eleven carbon atoms forming a ring. It is classed as an alkane because it has only carbon and hydrogen and these elements are configured with C–H and C–C such that there is a chain of carbon atoms with hydrogens attached to them. For each of the carbon atoms in the chain there is a pair of hydrogen atoms such that the chemical formula is CH. The compound is stable, but it burns with sufficient ignition heat.
Document 7: John Dalton: John Dalton FRS ( ; 6 September 1766 – 27 July 1844) was an English chemist, physicist, and meteorologist. He is best known for proposing the modern atomic theory and for his research into colour blindness, sometimes referred to as Daltonism in his honour.
Document 8: Charles Thomson Rees Wilson: Charles Thomson Rees Wilson, CH, FRS (14 February 1869 – 15 November 1959) was a Scottish physicist and meteorologist who won the Nobel Prize in Physics for his invention of the cloud chamber.
Document 9: Bicycloundecane: Bicycloundecane is an organic compound with molecular formula CH. It is essentially the spherical form of the ring cycloundecane. In cycloundecane, the eleven carbon atoms are joined together in a chain that meets at the ends to form a ring. In bicycloundecane, the eleven carbon atoms are arranged nearly spherically as two groups of four carbon atoms with a third group of three carbon atoms acting as a bridge. Each non-bridgehead carbon atom is attached to two hydrogen atoms making bicycloundecane a saturated compound. It is a bicycloalkane. Other related bicycloalkanes are bicyclooctane and bicyclononane.
Document 10: Vacuum flask: A vacuum flask (also known as a Dewar flask, Dewar bottle or thermos) is an insulating storage vessel that greatly lengthens the time over which its contents remain hotter or cooler than the flask's surroundings. Invented by Sir James Dewar in 1892, the vacuum flask consists of two flasks, placed one within the other and joined at the neck. The gap between the two flasks is partially evacuated of air, creating a near-vacuum which significantly reduces heat transfer by conduction or convection.
Document 11: Aromatic hydrocarbon: An aromatic hydrocarbon or arene (or sometimes aryl hydrocarbon) is a hydrocarbon with sigma bonds and delocalized pi electrons between carbon atoms forming a circle. In contrast, aliphatic hydrocarbons lack this delocalization. The term 'aromatic' was assigned before the physical mechanism determining aromaticity was discovered; the term was coined as such simply because many of the compounds have a sweet or pleasant odour. The configuration of six carbon atoms in aromatic compounds is known as a benzene ring, after the simplest possible such hydrocarbon, benzene. Aromatic hydrocarbons can be "monocyclic" (MAH) or "polycyclic" (PAH).
Document 12: Dewar benzene: Dewar benzene or bicyclo[2.2.0]hexa-2,5-diene is a bicyclic isomer of benzene with the molecular formula CH. The compound is named after James Dewar who included this structure in a list of possible CH structures in 1867. However, he did not propose it as the structure of benzene, and in fact he supported the correct structure previously proposed by August Kekulé in 1865.
Document 13: Phenyl group: In organic chemistry, the phenyl group or phenyl ring is a cyclic group of atoms with the formula CH. Phenyl groups are closely related to benzene and can be viewed as a benzene ring, minus a hydrogen,which may be replaced by some other element or compound to serve as a functional group. Phenyl groups have six carbon atoms bonded together in a hexagonal planar ring, five of which are bonded to individual hydrogen atoms, with the remaining carbon bonded to a substituent. Phenyl groups are commonplace in organic chemistry. Although often depicted with alternating double and single bonds, phenyl groups are chemically aromatic and show nearly equal bond lengths between carbon atoms in the ring.
Document 14: James Dewar: Sir James Dewar FRS FRSE (20 September 1842 – 27 March 1923) was a Scottish chemist and physicist. He is probably best known today for his invention of the vacuum flask, which he used in conjunction with extensive research into the liquefaction of gases. He was also particularly interested in atomic and molecular spectroscopy, working in these fields for more than 25 years.
Document 15: Johannes Diderik van der Waals: Johannes Diderik van der Waals (] ; 23 November 1837 – 8 March 1923) was a Dutch theoretical physicist and thermodynamicist famous for his work on an equation of state for gases and liquids.
ground_truth: 20 September 1842