ot by the absence of the sun, but by the presence
of the stars, which were the positive cause of the darkness. He
relates having seen a magnet capable of attracting the eyeball from
its socket as far as the tip of the nose; he knows of salves to close
the mouth so effectually that it has to be broken open again by
mechanical means, and he writes learnedly on the infallible signs of
witchcraft. By mixing horse-dung with human semen he believed he was
able to produce a medium from which, by chemical treatment in a
retort, a diminutive human being, or _homunculus_, as he called it,
could be produced. The spirits of the elements, the sylphs of the air,
the gnomes of the earth, the salamanders of the fire, and the undines
of the water, were to him real and undoubted existences in Nature.

Strange as all these beliefs seem to us now, they were a very real
factor in the intellectual conceptions of the Renaissance period, no
less than of the Middle Ages, and amidst them there is to be found at
times a foreshadowing of more modern knowledge. Many other persons
were also more or less associated with the magical school, amongst
them Franz von Sickingen. Reuchlin himself, by his Hebrew studies, and
especially by his introduction of the Kabbala to Gentile readers,
also contributed a not unimportant influence in determining the course
of the movement. The line between the so-called black magic, or
operations conducted through the direct agency of evil spirits, and
white magic, which sought to subject Nature to the human will by the
discovery of her mystical and secret laws, or the character of the
quasi-personified intelligent principles under whose form Nature
presented herself to their minds, had never throughout the Middle Ages
been very clearly defined. The one always had a tendency to shade off
into the other, so that even Roger Bacon's practices were, although
not condemned, at least looked upon somewhat doubtfully by the Church.
At the time of which we treat, however, the interest in such matters
had become universal amongst all intelligent persons. The scientific
imagination at the close of the Middle Ages and during the Renaissance
period was mainly occupied with three questions: the discovery of the
means of transmuting the baser metals into gold, or otherwise of
producing that object of universal desire; to discover the Elixir
Vitae, by which was generally understood the invention of a drug which
would have the effect of c