Clover's ether inhaler with Hewitt's valved stopcock, made by G Barth and Co. The first successful operation on a patient rendered unconscious by anaesthetic was carried out using ether in 1846. Ether was regarded as being safe to use, but it was slow to take its anaesthetic effect as well as being unpredictable with unpleasant side effects. Chloroform came to be preferred to ether as an anaesthetic. However, although quicker acting than ether, chloroform's poisonous nature meant it was a more dangerous substance to use. Today both have been superseded by safer, more effective anaesthetics.
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