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34－Adolescence
lijiao 490
33－Education
lijiao 236
32－Galileo Reborn
lijiao 239
31－The Sculptor Speaks
lijiao 258
30－Exploring the Sea-Floor
lijiao 318
29－The Hovercraft
lijiao 318
28－Patients and Doctors
lijiao 261
27－The vasa
lijiao 216
26－The Past Life of the Earth
lijiao 292
25－Non-Auditory Effects of Noise
lijiao 173
24－Beauty
lijiao 204
23－Bird Flight
lijiao 292
22－Knowledge and Progress
lijiao 172
21－William S. Hart and the Early Western Film
lijiao 244
20－Snake Poison
lijiao 169
19－The Stuff of Dreams
lijiao 375
18－Porpoises
lijiao 348
17－A Man-made Disease
lijiao 384
16－The Modern City
lijiao 204
15－Secrecy in Industry
lijiao 280