the
most pointed manner, that Tycho carried on his astronomical labours with
his mind entirely free from the superstitions of astrology; that he
derided and detested the vanity and knavery of astrologers, and was
convinced that the stars exercised no influence on the destinies of men.

[43] In his Preface to the Rudolphine Tables.

Although Tycho informed Rothman that he devoted as much labour and
expense to the study of terrestrial (chemistry) as he did to that of
celestial astronomy, yet it is a singular fact that he never published
any account of his experiments, nor has he left among his writings any
trace of his chemical inquiries. He pretended, however, to have made
discoveries in the science, and we should have been disposed to
reprobate the apology which he makes for not publishing them, did we not
know that it had been frequently given by the other alchemists of the
age--"On consideration," says he, "and by the advice of the most learned
men, I thought it improper to unfold the secrets of the art (of alchemy)
to the vulgar, as few persons were capable of using its mysteries to
advantage and without detriment."

Admitting then, as we must do, that Tycho was not only a professed
alchemist, but that he was practically occupied with its pursuits, and
continually misled by its delusions, it may not be uninteresting to the
reader to consider how far a belief in alchemy, and a practice of its
arts, have a foundation in the weakness of human nature; and to what
extent they are compatible with the piety and elevated moral feeling by
which our author was distinguished.

In the history of human errors two classes of impostors, of very
different characters, present themselves to our notice--those who
wilfully deluded their species, and those who permitted their species to
delude themselves. The first of those classes consisted of the selfish
tyrants who upheld an unjust supremacy by systematic delusions, and of
grovelling mountebanks who quenched their avaricious thirst at the
fountains of credulity and ignorance. The second class comprehended
spirits of a nobler mould: It embraced the speculative enthusiasts, whom
the love of fame and of truth urged onward, in a fruitless research,
and those great lights of knowledge and of virtue, who, while they stood
forward as the landmarks of the age which they adorned, had neither the
intellectual nor the moral courage to divest themselves of the
supernatural radiance with