Abraham Lincoln's blue pills - did our 16th president suffer from mercury poisoning?

It is well known that Abraham Lincoln took a medicine called "blue mass" or "blue pill," commonly prescribed in the 19th century. What is now hardly k nown is that the main ingredient of blue mass was finely dispersed elementa l mercury. As his friends understood, mercury was often prescribed for mela ncholy or "hypochondriasis:" a condition Lincoln famously endured. Mercury in the form of the blue pill is a potential neurotoxin, which we have demon strated by recreating and testing the recipe. We present the testimony of m any of Lincoln's contemporaries to suggest that Lincoln suffered the neurob ehavioural consequences of mercury intoxication but, perhaps crucial to his tory, before the main years of his presidency; he was astute enough to reco gnize the effects and stop the medication soon after his inauguration.