io6 JEROME CARDAN 



the same time the most chaotic, collection of the facts of 

 Natural Philosophy that had yet issued from the press. 

 The erudition and the industry displayed in the gather- 

 ing together of these vast masses of information, and in 

 their verification by experiment, are indeed amazing ; 

 and, in turning over his pages, it is impossible to stifle 

 regret that Cardan's confused method and incoherent 

 system should have rendered his work comparatively 

 useless for the spread of true knowledge, and qualified it 

 only for a place among the labores ineptiarum. 



Cardan begins with a definition of Subtilty. " By 

 subtilty I mean a certain faculty of the mind by which 

 certain phenomena, discernible by the senses and 

 comprehensible by the intellect, may be understood, 

 albeit with difficulty." Subtilty, as he understood it, 

 possesses a threefold character: substance, accident, and 

 manifestation. With regard to the senses he admits but 

 four to the first rank : touch, sight, smell, and hearing ; 

 the claims of taste, he affirms, are open to contention. 

 He then passes on to discuss the properties of matter: 

 fire, moisture, cold, dryness, and vacuum. The last- 

 named furnishes him with a text for a discourse on a 

 wonderful lamp which he invented by thinking out the 

 principle of the vacuum. This digression on the very 

 threshold of the work is a sample of what the reader 

 may expect to encounter all through the twenty-one 

 books of the De Subtilitate and the seventeen of the De 

 Varietate. Regardless of the claims of continuity, he 

 jumps from principle to practice without the slightest 

 warning. Intermingled with dissertations on abstract 

 causes and the hidden forces of Nature are to be found 

 descriptions of taps and pumps and syphons, and 

 | of the water-screw of Archimedes, the re-invention of 

 which caused poor Galeazzo Rosso, Fazio's blacksmith 



