GALILEO GALILEI. 3 



boy or girl can do best in the world, and then fit- 

 ting him or her for it ! 



While Galileo was studying medicine in Pisa, 

 boarding with a relative, the court of Tuscany 

 came to the city for a few months. Among the 

 suite was Ostilio Eicci, a distinguished mathemati- 

 cian, and Governor of the Pages of the Grand 

 Ducal Court. He was a friend of the Galilei fam- 

 ily, and was pleased to see the bright young son, 

 Galileo. When he taught Euclid, the medical 

 student would stand shyly at the schoolroom 

 door, and listen with intense interest. Soon he 

 began to study mathematics secretly ; then begged 

 Ricci to teach him, who gladly consented, till the 

 father forbade it, seeing that Euclid interfered 

 with medicine. 



Meantime, the youth of nineteen, kneeling at 

 prayers in the Pisa Cathedral, had dreamily 

 watched a bronze lamp swinging from an arch. 

 The oscillations were at first considerable, but as 

 they grew less and less, Galileo observed that 

 they were all performed in the same time, measur- 

 ing the time by feeling his pulse. The idea 

 occurred to him that an instrument could be con- 

 structed which should mark the rate and varia- 

 tion of the pulse. He began to experiment, and 

 soon invented the pulselogia, which the physicians 

 hailed with great delight. The pendulum was 

 not applied to clocks till a half-century later, 

 but its invention attracted the attention of all 

 scholars. 



