54 JEROME CARDAN 



fused because he did not see any prospect of being paid 

 for his services. His friend Filippo Archinto was loyal 

 still, and zealous in working for his success, and as he 

 had been recently promoted to high office in the Imperial 

 service, his good word might be very valuable indeed. 

 He summoned his prottgt to join him at Piacenza, 

 whither he had gone to meet Paul III., hoping to advance 

 Cardan's interests with the Pope ; but though Marshal 

 Brissac, the French king's representative, 1 joined Archinto 

 in advocating his cause, nothing was done, and Jerome 

 returned disappointed to Milan. 



In these months Cardan, disgusted by the failure of 

 his late attack upon the fortress of medical authority, 

 turned his back, for a time, upon the study of medicine, 

 and gave his attention almost entirely to mathematics, in 

 which his reputation was high enough to attract pupils, 

 and he always had one or more of them in his house, the 

 most noteworthy of whom was Ludovico Ferrari of Bo- 

 logna, who became afterwards a mathematician of repute, 

 and a teacher both at Milan and Bologna. While he 

 was working at the De Malo Medendi, he began a treatise 

 upon Arithmetic, which he dedicated to his friend Prior 

 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 



1 Cardan writes of Brissac : "Erat enim Brissacus Prorex singularis 

 in studiosis amoris et humanitatis." De Vita Propriety ch. iv. p. 14. 



