1803 Thomas Given Mahogany Octant with Accessories

• Ivory - Ivory is a hard white material that comes from the tusks of elephants, mammoth, walrus and boar, or from the teeth of hippopotamus and whales. The ivory from the African elephant is the most prized source of ivory. Although the mammoth is extinct, tusks are still being unearthed in Russia and offered for sale.
  
  Ivory has been used since the earliest times as a material for sculpture of small items, both in Europe and the east, principally China and Japan.
  
  In Asia ivory has been carved for netsuke, seals, okimono, card cases, fan supports, animals and other figures and even as carved tusks.
  
  In the last 200 years in Europe ivory has been used to carve figures, for elaborate tankards, snuff boxes, cane handles, embroidery and sewing accessories, in jewellery and as inlay on furniture. Its more practical uses include being used for billiard balls, buttons, and a veneers on the top of piano keys.
  
  The use and trade of elephant ivory have become controversial because they have contributed to Due to the decline in elephant populations because of the trade in ivory, the Asian elephant was placed on Appendix One of the Convention on International Trade in Endangered Species (CITES), in 1975, and in January 1990, the African elephant was similarly listed. Under Appendix One, international trade in Asian or African elephant ivory between member countries is forbidden. Unlike trade in elephant tusks, trade in mammoth tusks is legal.
  
  Since the invention of plastics, there have been many attempts to create an artificial ivory
• Oak - Native to Europe and England, oak has been used for joinery, furniture and building since the beginning of the medieval civilisation. It is a pale yellow in colour when freshly cut and darkens with age to a mid brown colour.
  
  Oak as a furniture timber was superceded by walnut in the 17th century, and in the 18th century by mahogany,
  
  Semi-fossilised bog oak is black in colour, and is found in peat bogs where the trees have fallen and been preserved from decay by the bog. It is used for jewellery and small carved trinkets.
  
  Pollard oak is taken from an oak that has been regularly pollarded, that is the upper branches have been removed at the top of the trunk, result that new branches would appear, and over time the top would become ball-like. . When harvested and sawn, the timber displays a continuous surface of knotty circles. The timber was scarce and expensive and was used in more expensive pieces of furniture in the Regency and Victorian periods.
• Verso - Verso is the "back" side of a sheet of paper, art work, coin or medal. The front side is "recto".
• Mahogany - Mahogany is a dense, close grained red-coloured timber from the West Indies and Central America. It was first imported into Europe in the the early 18th century and its use continued through the 19th century. It was popular for furniture making because of its strength, the wide boards available, the distinctive grain on some boards, termed flame mahogany and the rich warm colour of the timber when it was polished.. The "flame" was produced where a limb grew out from the trunk of the tree, and this timber was usually sliced into veneers for feature panels on doors, backs and cornices.
  
  Some terms used to describe mahogany relate to the country from which it originally came, such as "Cuban" mahogany, "Honduras" mahogany etc. However unless the wood has been tested the names assigned are more a selling feature, rather than a true indication of the timber's origin.

This item has been included into following indexes:

• shipping and nautical, fittings and equipment - plaques 30
• shipping and nautical, instruments - octant 24