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Hello, in 1660, Art Jukes of Vienna declared of their ruler. His majesty is interested only in wizards,

alchemists, cabalists and the like, sparing no expense to find all kinds of treasures, learn secrets and use scandalous ways of harming his enemies.

He also has a whole library of magic books. He strives all the time to eliminate God completely, so that he may, in future, serve a different master.

The subject of this attack was the Holy Roman Emperor Rudolf II and his courted Prague. Rudolf had filled Prague with the wonders of the age.

The great paintings of Italy were carried over the Alps, intricate automatons constructed, maps and models of the heavens unfold and engineered.

But Rudolf's greatest possessions were people. The astronomers Johannes Kepler and Tycho Brahe, the magus John D in the philosopher Shedano Bruni, had all found their way to his city.

Far from the devilish inquisitor of the Archduce imagination, Rudolf patronized a powerhouse of Renaissance ideas, with me to discuss the courted Rudolf II, a Howard Hodson, lecture in modern history at the University of Oxford.

Adam Mosley, lecturer in the Department of History at Swansea University and Peter Forscher, postdoctoral fellow at Berkbeck University of London.

Peter Forscher, and the Archduce Vosteromated, very clear that Rudolf was an intellectual curious man, a pursuer of secrets.

Can you explain broadly what sort of secrets he would have been pursuing?

I have to say almost everything, really, but one Venetian visitor observes that he's anyone who can give him knowledge of secrets of natural and artificial things will gain his ear.

By natural, that's the three kingdoms of animal, vegetable and mineral, and artificial can be artistic creations, but also mechanical objects, scientific instruments and so forth.

Particularly to do with the celestial and terrestrial, on the terrestrial level, the science particularly of alchemy, and obviously with the celestial astronomy.

They're pretty tough aren't they, with the business of wizards, alchemists, cavalists, scandalous ways, how true is all that?

There's no doubt that really Prague was the magnet for anyone who was a practitioner for the occult arts.

So, alchemists really knew that Rudolf was a grand patron of alchemy.

At the heyday, at the height of his interest in alchemy, 200 alchemists and their assistants were working in the laboratories at the palace in Prague.

Could you just address this person of alchemy for a moment, Peter, because we're at the height of the intellectual interest and relief in a pursuit of alchemical.

So, just tell us how important that was to learning at the time.

To learning extremely important, it wasn't yet a university-based discipline.

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