SEISMOLOGIOAL PHENOMENA, 203 



Rossi-FoREL Scale of Intensity. 



I. Recorded by a single seismograph, or by some seismographs 

 of the same model, but not by several seismographs of" different 

 Icinds ; the shock felt by an experienced observei*. 



II. Recorded by seismographs of different kinds; felt by a 

 small number of persons at rest. 



III. Felt by several persons at rest; strong enough for the 

 duration or the direction to be appreciable. 



IV. Felt by persons in motion ; disturbance of moveable 

 objects, doors, windows, cracking of ceilings. 



V. Felt generally by everyone ; disturbance of furniture and 

 beds, ringing of some bells, 



VI. General awakening of those asleep ; general ringing of 

 bells, oscillation of chandeliers, stopping of clocks ; visible dis- 

 turbance of trees and shrubs. Some startled persons leave their 

 dwellings. 



VII. Overthrow of moveable objects, fall of plaster, ringing of 

 church bells, general ))anic, without damage to buildings. 



VIII. Fall of chimneys, cracks in the walla of buildings. 



IX. Partial or total destruction of some buildings. 



X. Great disasters, ruins, disturbance of strata, fissures in the 

 earth's crust, rock-falls from mountains. 



