What distinguished the true alchemist from the fraud? This question animated the lives and labors of the common men – and occasionally women – who made a living as alchemists in the sixteenth- and seventeenth-century Holy Roman Empire. As purveyors o...

Today we are all familiar with the iconic pictures of the nebulae produced by the Hubble Space Telescope's digital cameras. But there was a time, before the successful application of photography to the heavens, in which scientists had to rely on hand...