Gaddi; but this work was not published till
1539. In 1536 he first heard a report of a fresh and important discovery
in algebra, made by one Scipio Ferreo of Bologna; the prologue to one of
the most dramatic incidents in his career, an incident which it will be
necessary to treat at some length later on.

Cardan was well aware that his excursions into astrology worked to his
prejudice in public esteem, but in spite of this he could not refrain
therefrom. It was during the plentiful leisure of this period that he
cast the horoscope of Jesus Christ, a feat which subsequently brought upon
him grave misfortune; a few patients came to him, moved no doubt by the
spirit which still prompts people suffering from obscure diseases to
consult professors of healing who are either in revolt or unqualified in
preference to going to the orthodox physician. In connection with this
irregular practice of his he gives a curious story about a certain Count
Borromeo. "In 1536, while I was attending professionally in the house of
the Borromei, it chanced that just about dawn I had a dream in which I
beheld a serpent of enormous bulk, and I was seized with fear lest I
should meet my death therefrom. Shortly afterwards there came a messenger
to summon me to see the son of Count Carlo Borromeo. I went to the boy,
who was about seven years old, and found him suffering from a slight
distemper, but on feeling his pulse I perceived that it failed at every
fourth beat. His mother, the Countess Corona, asked me how he fared, and I
answered that there was not much fever about him; but that, because his
pulse failed at every fourth beat, I was in fear of something, but what it
might be I knew not rightly (but I had not then by me Galen's books on the
indications of the pulse). Therefore, as the patient's state changed not,
I determined on the third day to give him in small doses the drug called
_Diarob: cum Turbit_: I had already written my prescription, and the
messenger was just starting with it to the pharmacy, when I remembered my
dream. 'How do I know,' said I to myself, 'that this boy may not be about
to die as prefigured by the portent above written? and in that case these
other physicians who hate me so bitterly, will maintain he died through
taking this drug.' I called to the messenger, and said there was wanting
in the prescription something which I desired to add. Then I privately
tore up what I had written, and wrote out another made of pearl