signatures, physiognomy, chiromancy, gnomes, sylphs and 

 parallels of celestial and terrestrial bodies, all of which in- 

 fluenced his medical practice; yet Croll described many chemi- 

 cal substances and reactions with comparative accuracy and 

 showed admirable knowledge of human nature when he 

 wrote: "It is the principal part of a physician that would 

 cure the sick first to comfort the heart and afterwards to 

 assault the disease". 



Anselm Boethius de Boodt, of Bruges in Flanders, the 

 favorite physician of Rudolph in his later }^ears, was especially 

 esteemed on account of his great learning in gems and pre- 

 cious stones; his "History of Gems and Stones," published in 

 1609, is still recognized as an important treatise and very 

 creditable for the time. Boethius had another claim to 

 Rudolph's appreciation being an advocate of the verity of 

 transmutation, a belief acquired in the following manner: 

 when still a young student of medicine he accidentH r found 

 among his father's books an antique manuscript entitled 

 "Cytnbalum aureum," written on parchment and covered 

 with two half-broken, thick boards; wishing to re-cover the 

 book he removed the boards and discovered in one a cavity 

 containing a small piece of paper folded tight; on examining 

 this he perceived a few grains of a red powder and some 

 hieroglyphical \vords on the inner surface of the paper. By 

 hard study the young man deciphered the writing and found 

 that it explained the process of using the powder in trans- 

 mutation; he made an experiment on mercury heated in a 

 crucible and the red powder changed the metal in one quarter 

 of an hour into fine gold. Unfortunately he used the whole 

 amount of the powder at one operation, but this experience 

 served to convince him of the verity of alchemy. . 



Although Boethius de Boodt was really learned in pre- 

 cious stones, crystals, corals and shells, he shared the super- 



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or THE 

 UNIVERSITY 



