Science also has had its martyrs, who have fought their way to light through difficulty, persecution, and suffering. We need not refer again to the cases of Bruno, Galileo, and others, [216] persecuted because of the supposed heterodoxy of their views. But there have been other unfortunates amongst men of science, whose genius has been unable to save them from the fury of their enemies. Thus Bailly, the celebrated French astronomer [21who had been mayor of Paris], and Lavoisier, the great chemist, were both guillotined in the first French Revolution. When the latter, after being sentenced to death by the Commune, asked for a few days' respite, to enable him to ascertain the result of some experiments he had made during his confinement, the tribunal refused his appeal, and ordered him for immediate execution--one of the judges saying, that "the Republic had no need of philosophers." In England also, about the same time, Dr. Priestley, the father of modern chemistry, had his house burnt over his head, and his library destroyed, amidst shouts of "No philosophers!" and he fled from his native country to lay his bones in a foreign land. The work of some of the greatest discoverers has been done in the midst of persecution, difficulty, and suffering. Columbus, who discovered the New World and gave it as a heritage to the Old, was in his lifetime persecuted, maligned, and plundered by those whom he had enriched. Mungo Park's drowning agony in the African river he had discovered, but which he was not to live to describe; Clapperton's perishing of fever on the banks of the great lake, in the heart of the same continent, which was afterwards to be rediscovered and described by other explorers; Franklin's perishing in the snow--it might be after he had solved the long-sought problem of the North-west Passage--are among the most melancholy events in the history of enterprise and genius.