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James Dunlop

James Dunlop FRSE was a Scottish astronomer, noted for his work in Australia. He served as astronomer's assistant, hired by Sir Thomas Brisbane to work at his private observatory, once located at Paramatta, New South Wales, about 23 kilometres west of Sydney during the 1820s and 1830s. Dunlop was a visual observer, doing stellar astrometry work for Brisbane, after its completion independently discovered and catalogued many new telescopic southern double stars and deep-sky objects, he became the Superintendent of Paramatta Observatory when it was sold to the New South Wales Government. James Dunlop was born in Dalry, Scotland, the son of John Dunlop, a weaver, his wife Janet, née Boyle. Dunlop was educated at a primary school in Dalry and went to work at a thread factory in Beith when he was 14, he attended a night-school in Beith kept by a man named Gardiner. He became interested in astronomy at an early age and was constructing telescopes in 1810. By fortune in 1820, he made the acquaintance of the astronomically inclined Sir Thomas Brisbane.

In the same year, Brisbane was appointed as the new Governor of New South Wales, who decided to set up an astronomical observatory in the new Colony. Prior to leaving Britain, Dunlop was appointed as his second scientific assistant, both travelled to Sydney in 1821. Soon after arriving, Brisbane immediately started building his observatory at Paramatta, now named Parramatta, it was Dunlop, employed to do the astrometric observations for a new accurate southern star catalogue. Employed was the German born Carl Ludwig Christian Rümker, or Karl Rümker, recruited by Brisbane as first astronomical assistant. Rümker soon left the observatory in protest of his treatment during 1823, leaving Dunlop in charge of the astrometric measures and general maintenance of the astronomical instruments and the Observatory. Dunlop was not a professionally trained astronomer, so he lacked the necessary mathematical skills to do astrometric reductions, he had soon learned the necessary observational skills from his employer.

Between June 1823 and February 1826 Dunlop made 40,000 observations and catalogued some 7,385 stars, of which included 166 double stars and references to several bright deep-sky objects near the bright stars he catalogued. By the beginning of March 1826, he left the Paramatta Observatory and continued working at his own home in Hunter Street, Paramatta. For there he began organising his own observations of double stars and deep-sky objects for the next 18 months, in which he constructed telescopes and other equipment for his dedicated southern sky survey. Sir Thomas Brisbane, before departing Sydney for the last time in December 1825, arranged to sell all of his instruments to the Government so the observatory could continue to function; some of the equipment he gave to Dunlop, which he used at his home the useful small equatorial mounted 8.0 centimetres refracting telescope that Rümker, Dunlop, both used for doing the important double stars measures as their own personal projects. By May 1826, Rümker returned to the observatory, seven months he was appointed as the first New South Wales Government Astronomer, though this did not happen until a few years much to Rümker's disgust, due to delays from his employers in Britain.

Dunlop left Sydney for Scotland in February 1827 and was employed for four years at the observatory of Sir Thomas Brisbane. He had done good work as an observer in New South Wales, was associated with Rümker in the recovery of Comet Encke at Parramatta in June 1822, he was to be the first in Great Britain to rediscover this comet on 26 October 1829. He had been awarded the Gold Medal of the Royal Astronomical Society of London on 8 February 1828. Sir John Herschel, when making the presentation, spoke in the highest terms of the value of the work done by Dunlop in New South Wales. On arrival, he reduced his southern double stars and deep-sky observations for publication, believed to have taken about one month, these were published in the first half of 1828; these two detailed astronomical papers were received with many accolades from his peers, which lasted until about 1834, when his observations were able to be scrutinised by John Herschel and Thomas Maclear in South Africa. Only were the various flaws of his observations revealed, the time spent in the zenith of popularly dwindled to fierce criticism and personal rejection from the British astronomical community.

In April 1831, Dunlop was appointed superintendent of the Government observatory at Parramatta. He was selected from his good knowledge of Colony and the observatory site, but the real reason for his selection was more because though such an astronomical position was formally advertised, nobody applied for the astronomical tenure. Here he was to succeed Rümker with the reasonable good salary of £300 a year, he found the observatory in a deplorable condition. Dunlop succeeded in getting the building repaired and started on his work with energy, but around 1835 his health began to fail. In August 1847, he resigned his position, went to live on his farm on Brisbane Waters, an arm of Broken Bay, he died on 22 September 1848. In 1816 Dunlop married his cousin Jean Se

Geology of Turkey

The geology of Turkey is the product of a wide variety of tectonic processes that have shaped Anatolia over millions of years, a process which continues today as evidenced by frequent earthquakes and occasional volcanic eruptions. Turkey's terrain is structurally complex. A central massif composed of uplifted blocks and downfolded troughs, covered by recent deposits and giving the appearance of a plateau with rough terrain, is wedged between two folded mountain ranges that converge in the east. True lowland is confined to the plain of the Ergene river in Thrace, extending along rivers that discharge into the Aegean Sea or the Sea of Marmara, to a few narrow coastal strips along the Black Sea and Mediterranean Sea coasts. Nearly 85% of the land is at an elevation of at least 450 meters. In Asiatic Turkey, flat or sloping land is rare and confined to the deltas of the Kızıl River, the coastal plains of Antalya and Adana, the valley floors of the Gediz River and the Büyük Menderes River, some interior high plains in Anatolia around Tuz Gölü and Konya Ovası.

Moderately sloping terrain is limited entirely outside Thrace to the hills of the Arabian Platform along the border with Syria. More than 80% of the land surface is rough and mountainous, therefore is of limited agricultural value; the terrain's ruggedness is accentuated in the eastern part of the country, where the two mountain ranges converge into a lofty region with a median elevation of more than 1,500 meters, which reaches its highest point along the borders with Armenia and Iran. Turkey's highest peak, Mount Ararat —about 5,166 meters high—is situated near the point where the boundaries of the four countries meet; the earliest geological history of Turkey is poorly understood because these oldest rocks in the region are involved into younger deformation phases that hindered their evolution. This created problem of reconstructing how the region has been tectonically assembled by plate motions. Turkey can be thought of as a collage of different continental pieces and remnants of oceanic lithospheric rocks amalgamated together by younger tectonic processes that involve accumulation of igneous and sedimentary rocks.

Except for a small portion of its territory along the Syrian border, a continuation of the Arabian Plate, Turkey geologically is part of the great Alpine belt that extends from the Atlantic Ocean to the Himalaya Mountains. This belt was formed during the Cenozoic Era, as the Arabian and Indian continental plates began to collide with the Eurasian Plate; this process is still at work today as the African Plate converges with the Eurasian Plate and the Anatolian Plate escapes towards the west and southwest along strike-slip faults. These are the North Anatolian Fault Zone, which forms the present day plate boundary of Eurasia near the Black Sea coast and, the East Anatolian Fault Zone, which forms part of the boundary of the North Arabian Plate in the southeast; as a result of this plate tectonics configuration, Turkey is one of the world's more active earthquake and volcanic regions. The Anatolian Plate, together with the Aegean-Peloponnesus block, is located near the centre of a wide region, including the Arabian Plate with the adjacent Zagros Mountains and central Iran, that moves in a circulatory pattern at a fast rate of 20 mm/yr.

The rate of this counter-clockwise motion increases near the Hellenic Trench system south of Turkey and decreases away from it, resulting in internal deformations in several areas, including central and eastern Anatolia, south-western Aegean-Peloponnesus, Lesser Caucasus, central Iran. The dominant process in the region is the subduction of the African Plate beneath the Hellenic Trench, the deformation in the entire African-Arabian-Eurasian collision zone is most driven by the slab roll-back of the subducting African Plate in the East Mediterranean; this process is further fuelled by slab-pull forces in the Makran Trench in the Gulf of Oman where the Arabian Plate is subducting under Eurasia. A response to this tectonic maelstrom is the rifting in the Red Sea and Gulf of Aden which will separate Arabia from Africa. Many of the rocks exposed in Turkey were formed. Turkey contains outcrops of Precambrian rocks. During the Mesozoic era a large ocean, floored by oceanic lithosphere existed in-between the supercontinents of Gondwana and Laurasia.

This large oceanic plate was consumed at subduction zones. At the subduction trenches the sedimentary rock layers that were deposited within the prehistoric Tethys Ocean were folded and tectonically mixed with huge blocks of crystalline basement rocks of the oceanic lithosphere; these blocks form a complex mixture or mélange of rocks that include serpentinite, basalt and chert. The Eurasian margin, now preserved in the Pontides, is thought to have been geologically similar to the Western Pacific region today. Volcanic arcs and back-arc basins formed and were emplaced onto Eurasia as ophiolites as they collided with microcontinents; these microcontinents had been pulled away from the Gondwanan continent further south. Turkey is therefore made up from several different prehistorical microcontinents. During the Cenozoic folding and uplifting, accompanied by