User:Aplacey/sandbox

Discovery of chlorine
Chlorine was discovered in 1774 by Swedish chemist Carl Wilhelm Scheele, who called it "dephlogisticated marine acid" (see phlogiston theory) and mistakenly thought it contained oxygen. Davy showed that the acid of Scheele's substance, called at the time oxymuriatic acid, contained no oxygen. This discovery overturned Lavoisier's definition of acids as compounds of oxygen. In 1810, chlorine was given its current name by Humphry Davy, who insisted that chlorine was in fact an element. The name chlorine, chosen by Davy for 'one of [the substance's] obvious and characteristic properties - its colour', comes from the Greek χλωρος (chlōros), meaning green-yellow.

Work on the electrochemical protection of ships' copper bottoms
From 1761 onwards, copper plating had been fitted to the underside of Royal Navy ships, to protect the wood from attack by shipworms. However, the copper bottoms were gradually corroded by exposure to the salt water. Between 1820-25, Davy, assisted by Michael Faraday, attempted to protect the copper by electrochemical means. He attached sacrificial pieces of zinc or iron to the copper, which provided cathodic protection to the host metal. It was discovered, however, that protected copper became foul quickly, i.e. pieces of weed and/or marine creatures became attached to the hull, which had a detrimental effect the handling of the ship. The Navy Board approached Davy in 1822, asking for help. Davy conducted a number of tests in Portsmouth Dockyard, on the ships HMS Royal George, HMS Samarang, and HMS Manly.JAMES The Navy Board adopted the use of Davy's 'protectors'. By 1824, it had become apparent that fouling of the copper bottoms was still occurring on the majority of 'protected' ships. By the end of 1825, the Admiralty ordered the Navy Board to cease fitting the protectors to sea-going ships, and to remove those that had already been fitted. Davy's scheme was seen as a public failure, despite the fact that, as Frank A. J. L. James comments, 'The somewhat ironical problem [...] was not that they were unsuccessful. They did after all preserve the copper as Davy said they would. The problem was that the protectors, on most ships, a chemical side effect which provided nutrients for weeds, barnacles etc. thus fouling the ships'.JAMES