THE SEVEEE JAPAN EAETHQUAKE OF THE 15th OF JANUARY, 1887. 



321 



have lived for centuries amidst terrible shakings, and who, no douht, 

 have gained much experience in the constructive arts suitable to the 

 conditions of our existence here. 



A prominent feature in the etfects of the recent earthc^iake was cMmneys. 

 the overthrowing of brick chimneys in Yokohama, especially on the 

 "Bluff. Soon after the shock, circulars were sent round to the princi- 

 pal residents, asking for information as to the effects of the shock on 

 the buildings occupied by them. More than fifty answers were 

 received, and the facts embodied in them have been of great value in 

 preparing this paper. The w^riter takes this o]"!portunity of express- 

 ing his warmest thanks for the kind assistance thus rendered to him. 

 From these answers, from the Police Reports, and from actual obser- 

 vations fifty-three chimneys appear to have been destroyed. In one 

 instance a heavily- coped chimney fell in a large mass through the 

 roof, and severing a strong beam of 1 ft", by 8 in. on the second 

 story, penetrated to the ground floor. 



About one-half of the chimneys thrown down during the shock 

 were cut in two at their junction with the roof; while some dislodged 

 the tiling and did sundry other damage to the buildings at their 

 points of contact. Evidently the chimneys and the houses moved 

 with unequal range and wàth different vibrational periods. Professor 

 Milne has more than once recommended that chimneys should be 

 built thick and scpiat, without heavy ornamental mouldings or cop- 

 ings; and be, if possible, disconnected from the roofs. Those houses 

 in which his suggestions had been adopted suffered no damage on the 

 15th of January. 



Generally, the relations of the seismic effects to the sfeoloofical, Nature ot 



»^ ' O o ' rooks and 



topographical and other features of the various localities were found fea°S! "^"^ 

 to corroborate previous experience. That the seismic vibrations in 

 hard ground are very much less than in soft soil was w^ell ilhistrated 



