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Joseph Black (16 April 1728 – 6 December 1799) was a Scottish physicist and chemist, known for his discoveries of magnesium, latent heat, specific heat, and carbon dioxide.
The chemical elements were discovered in identified minerals and with the help of the identified elements the mineral crystal structure could be described. One milestone was the discovery of the geometrical law of crystallization by René Just Haüy , a further development of the work by Nicolas Steno and Jean-Baptiste L. Romé de l'Isle (the ...
The earliest gold metallurgy is known from the Varna culture in Bulgaria, dating from c. 4600 BC. [6] Silver, copper, tin and meteoric iron can also be found native, allowing a limited amount of metalworking in ancient cultures. [7] Egyptian weapons made from meteoric iron in about 3000 BC were highly prized as "daggers from Heaven". [8]
Vauquelin discovered the oxide in beryl and emerald in 1798, and in 1808 Davy showed that this oxide has a metallic base although he could not isolate it. [ 64 ] [ 106 ] Vauquelin was uncertain about the name to give to the oxide: in 1798 he called it la terre du beril , but the journal editors named it glucine after the sweet taste of ...
Produced oxygen gas by heating mercuric oxide and various nitrates by about 1772. Scheele called the gas 'fire air' because it was the only known supporter of combustion, and wrote an account of this discovery in a manuscript he titled Treatise on Air and Fire, which he sent to his publisher in 1775.
Candle moulding machine in Indonesia circa 1920. Candle making was developed independently in a number of countries around the world. [1]Candles were primarily made from tallow and beeswax in Europe from the Roman period until the modern era, when spermaceti (from sperm whales) was used in the 18th and 19th centuries, [2] and purified animal fats and paraffin wax since the 19th century. [1]
Wax candle. Waxes such as paraffin wax or beeswax, and hard fats such as tallow are used to make candles, used for lighting and decoration. Another fuel type used in candle manufacturing includes soy. Soy wax is made by the hydrogenation process using soybean oil.
Metallurgy derives from the Ancient Greek μεταλλουργός, metallourgós, "worker in metal", from μέταλλον, métallon, "mine, metal" + ἔργον, érgon, "work" The word was originally an alchemist's term for the extraction of metals from minerals, the ending -urgy signifying a process, especially manufacturing: it was discussed in this sense in the 1797 Encyclopædia ...