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Dragon's Blood
Dragon's blood is a bright red resin which is obtained from different species of a number of distinct plant genera: '' Calamus'' spp. (previously ''Daemonorops'') also including '' Calamus rotang'', '' Croton'', '' Dracaena'' and ''Pterocarpus''. The red resin has been in continuous use since ancient times as varnish, medicine, incense, pigment, and dye. Name and source A great degree of confusion existed for the ancients in regard to the source and identity of dragon's blood. Some medieval encyclopedias claimed its source as the literal blood of elephants and dragons who had perished in mortal combat. The resin of '' Dracaena'' species, "true" dragon's blood, and the very poisonous mineral cinnabar (mercury sulfide) were often confused by the ancient Romans. In ancient China, little or no distinction was made among the types of dragon's blood from the different species. Both ''Dracaena'' and '' Calamus'' resins are still often marketed today as dragon's blood, with little or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Dragon's Blood (Daemomorops Draco)
Dragon's blood is a bright red resin which is obtained from different species of a number of distinct plant genera: ''Calamus (palm), Calamus'' spp. (previously ''Daemonorops'') also including ''Calamus rotang'', ''Croton (plant), Croton'', ''Dracaena (plant), Dracaena'' and ''Pterocarpus''. The red resin has been in continuous use since ancient times as varnish, medicine, incense, pigment, and dye. Name and source A great degree of confusion existed for the ancients in regard to the source and identity of dragon's blood. Some medieval encyclopedias claimed its source as the literal blood of elephants and dragons who had perished in mortal combat. The resin of ''Dracaena (plant), Dracaena'' species, "true" dragon's blood, and the very poisonous mineral cinnabar (mercury sulfide) were often confused by the ancient Romans. In ancient China, little or no distinction was made among the types of dragon's blood from the different species. Both ''Dracaena'' and ''Calamus (palm), Cal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Endemic (ecology)
Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can also be referred to as an ''endemism'' or, in scientific literature, as an ''endemite''. Similarly, many species found in the Western ghats of India are examples of endemism. Endemism is an important concept in conservation biology for measuring biodiversity in a particular place and evaluating the risk of extinction for species. Endemism is also of interest in evolutionary biology, because it provides clues about how changes in the environment cause species to undergo range shifts (potentially expanding their range into a larger area or bec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
George Field (chemist)
George Field (1777?–1854), was an English chemist. He was born in or about 1777 at Berkhamsted, Hertfordshire, of a family long settled in that town, and was educated at St. Peter's school there. When about eighteen years of age he came to London to seek a profession. He thought he saw an opening in the careful application of chemistry to pigments and dyes. War on the continent, by stopping the supply of madder from Holland, threatened to impede his progress. This obstacle, however, led him to consider the nature of its cultivation, and with a well-devised project he waited on Sir Joseph Banks for his advice, and, as he hoped, his co-operation. Sir Joseph, after unsuccessfully attempting to cultivate madder in Essex, had made up his mind that it could not be done in England. Horticulture and inventions Field then commenced the cultivation in his own garden, and from roots of his own growth produced beautiful specimens of colouring matter. A contrivance, both mechanical and che ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
