PROGRESS IN ANTIQUITY. 21 



406366. Eudoxus, who had built an observatory at 

 Cnidos, was the first to enunciate the REGULARITY OF 

 MOTION of the planets in the heavenly sphere, thereby 

 explaining their periodic reappearance in the same place, 

 and to make a map of the known stars. It is probable, 

 however, that this knowledge had been in the possession 

 of the Chaldaeans and the Egyptians for many centuries ; 

 but the fact that he had an observatory is full of significance. 



362 287. Theophrastus composed a history of Stones 

 and a history of Plants ; another work, called " On the Cause 

 of Plants" on gardening and farming, is one of the most 

 practical ever written combining, as it does, pure science 

 with applied knowledge. It remained a text-book until 

 modern botany came into existence. Theophrastus must be 

 recognised as the FOUNDER OF BOTANY. His descriptions 

 embraced 500 different species of plants, which are grouped 

 or divided into herbs, shrubs, and trees a very misleading 

 CLASSIFICATION, but a most creditable attempt, nevertheless, 

 being based as it was upon direct observation. He was the 

 first to record the discovery of fossil bones and ivory this 

 being the earliest gleam of Palaeontology after Aristotle *, but 

 two thousand years will pass away before this science is 

 born. 



330. Calippus corrected the Metonic cycle (which caused 

 an error of one day in 317 years) by establishing (in 330) 

 the CALIPPIC PERIOD of 940 lunations a cycle of 76 years 

 minus one day. These cycles were intended also to be 

 cycles of eclipses, but they were only approximate in this 

 respect. Calippus assisted Aristotle in correcting Eudoxus's 

 discoveries. This affords another proof of the practical 

 influence of Aristotle and of his method of verification. 



330. Berosus invented the HEMISPHERE, one of the 

 most ancient instruments next to the gnomon and the dioptra. 



323 285. Herophilus, a worthy successor of Hippo- 

 crates, ascribed the pulse to the CONTRACTION OF THE 

 HEART ; was the first to recognise the importance of care- 

 fully noting three things in the PULSE the strength, the 

 quickness, and the regularity of its beats. He was aware 

 of the existence of the lacteals, and their relation to the 



