SCIENCE AND PRACTICAL NEEDS 9 



Excavations in Assyria and Babylonia, especially 

 since 1843, have brought to our knowledge an an- 

 cient culture stretching back four or five thousand 

 years before the beginning of the Christian era. The I* 

 records of Assyria and Babylonia, like those of Egypt, 

 are fragmentary and still in need of interpretation. 

 Here again, however, it is the fundamental, the in- 

 dispensable, the practical forms of knowledge that 

 stand revealed rather than the theoretical, specula- 

 tive, and purely intellectual. 



By the Babylonian priests the heavens were made 

 the object of expert observation as early as 3800 B.C. 

 The length of the year, the length of the month, the 

 coming of the seasons, the course of the sun in the 

 heavens, the movements of the planets, the recur- 

 rence of eclipses, comets, and meteors, were studied 

 with particular care. One motive was the need of a 

 measurement of time, the same motive as underlies 

 the common interest in the calendar and almanac. 

 It was found that the year contained more than 365 

 days, the month (synodic) more than 29 days, 12 

 hours, and 44 minutes. The sun's apparent diameter 

 was contained 720 times in the ecliptic, that is, in 

 the apparent path of the sun through the heavens. 

 Like the Egyptians, the Babylonians took special 

 note of the stars and star-groups that were to be 

 seen at dawn at different times of the year. These 

 constellations, lying in the imaginary belt encircling 

 the heavens on either side of the ecliptic, bore names 

 corresponding to those we have adopted for the signs 

 of the zodiac, Balance, Ram, Bull, Twins, Scor- 

 pion, Archer, etc. The Babylonian astronomers also 

 observed that the successive vernal (or autumnal) 



