George Washington had the finest medical care available. Unfortunately, given the primitive medicine of the era, that wasn't nearly enough to save him. While it is probably unlikely that he would have survived his final illness, the aggressive treatment that the great statesman received certainly didn't help. His doctors blistered his skin (to draw off "humours"), gave him frequent bleedings (Martha Washington had objected to the bleedings but her husband overrode her), and applied poultices of wheat bran. They also purged him with mercurous chloride to empty his bowels. After growing weaker and finally asking his doctors to leave him alone, George Washington died on December 14, 1799 at the age of 67. The exact nature of his final illness remains unclear but modern historians believe it may have been diphtheria or strep throat. The medical care that he received almost certainly played a role as well (not that he would be the last U.S. president to be killed by well-intentioned doctors).
Mercury, a.k.a. quicksilver or hydrargium, has always fascinated philosophers, chemists, and healers alike. Its silvery appearance, tendency to stay liquid at room temperature, and chemical properties made it a natural ingredient for numerous remedies. Records show that it was used in medicine as early as the second century AD when the Chinese philosopher Pao Pu Tzu recommended mixing pills combining cinnabar (mineralized mercury sulphide) and honey to make patients immortal (the absence of immortals these days would suggest that this hopeful concoction didn't work). The great Greek healer, Hippocrates swore to mercury's medical value and it was also used in traditional remedies for diseases such as smallpox and syphilis.
Thomas Dover (1660-1742) wrote that "to take an ounce of quicksilver every morning is the most beneficial thing in the world". Mercury was the treatment of choice for syphilis (despite the fact that it did nothing to prevent the onset of dementia or death) but was most widely used in the form of mercurous chloride (better known as calomel). For centuries, the calomel "blue pills" were dispensed by physicians to children and adults as an all-purpose diuretic and laxative. Benjamin Rush, the 18th century dean of American medicine, marketed a personal concoction that he often prescribed for his patents. His "bilious pills" were made up of mercury and jalap (a popular purgative) and Rush swore by their effectiveness (although contemporary critics noted the increased mortality rate in his patients). A journalist of the time referred to Rush's work as "one of those great discoveries which have contributed to the depopulation of the earth".
The effect of mercury-based remedies on patients was certainly noted by physicians and medical horror stories became common. In one medical text published in 1835, several case histories of mercury poisoning were reported: "a boy, about eleven years old, had a sore on once cheek, occasioned by a dentist extracting a tooth; a physician was consulted, who immediately prescribed a course of mercury. In a short time, ulcerations in the throat appeared, the nose sunk and one eye was nearly destroyed; while the general health was so injured, that death followed in a few months". Despite the warnings surrounding mercury use, physicians were slow to accept that they were poisoning their own patients and would continue using calomel well into the 20th century.
Mercury use was hardly limited to medicine. There have been countless industrial applications for mercury compounds although this has declined in recent decades as the neurotoxic aspects of mercury became better known. Mercury continues to be an ingredient in some medications despite ongoing controversy over safe levels of exposure. I won't even try to get into the controversies surrounding mercury exposure in dental amalgams and vaccines. It does seem ironic that activists have attempted to link mercury to autism despite the syndrome being first identified in 1943. Given that children were routinely dosed with dangerous levels of mercury for centuries, it's hard not to wonder why autism cases are rising now despite mercury exposure in children being so greatly reduced.
While many European nations have called for a total ban on mercury use, it's unlikely that the silvery metal's influence will end any time soon.