CONTENTS. XI 



CHAPTEK YI. 



EFFECTS PRODUCED BY EARTHQUAKES UPON BUILDINGS. 



PAGK 



The destruction of bnildings is not irregular — Cracks in buildings — 

 Buildings in Tokio — Relation of destruction to earthqiiake 

 motion — Measurement of relative motion of parts of a building 

 shaken by an earthquake — Prevention of cracks- Direction of 

 cracks — The pitch of roofs — Relative position of openings in a 

 wall— The lasi house in a row — The swing of buildings — Prin- 

 ciple of relative vibrational periods 96 



CHAPTER YII. 



EFFECTS PRODUCED UPON BUILDINGS {continued). 



Types of buildings used in earthquake countries — In Japan, in Italy, 

 in South America, in Caraccas — Typical houses for earthquake 

 countries — Destruction due to the nature of underlying rocks — 

 The swing of mountains — Want of support on the face of hills — 

 Earthquake shadows — Destruction due to the interference of 

 waves — Earthquake bridges — Examples of earthquake effects — 

 Protection of buildings — General conclusions , , , 122 



CHAPTER YIII. 



EFFECTS OF EARTHQUAKES ON LAND. 



1. Cracks and fissures — Materials discharged fi-om fissures — Ex- 

 planation of fissure phenomena. 2. Disturbances in lakes, rivers, 

 springs, wells, fumaroles, &c. — Explanation of these latter phe- 

 nomena. 3. Permanent displacement of ground — On coast lines 

 — Level tracts — Among mountains — Explanation of these move- 

 ments , 146 



CHAPTER IX. 



DISTURBANCES IN THE OCEAN. 



Sea xib rations— Cause of vibratoiy blows— Sea waves : preceding 

 earthquakes; succeeding earthquakes — Mag-nitude of waves — 



