THE GREAT EARTHQUAKE OF PORT ROYAL. 779 



suddenly disappeared, the sea rolling completely over the . place 

 where it had stood. Then the whole of that portion of the town 

 where the ship-channel had been sank at once into deep water, 

 while the houses nearer the central rock sank, some up to the 

 eaves, others up to the first floor, and others again one or two feet 

 only, according to the distance at which they were situated from 

 the water's edge. The shock of the earthquake, in fact, shook 

 down the artificially sustained bank of sand ; as the sand shook 

 down and spread out, the houses subsided, while the sea, rushing 

 in underneath as well as above, gushed up in spouts in the streets 

 and completed the ruin. Fort Charles and the houses that stood 

 on the rock foundation alone remained, and of these the greater 

 number were terribly shattered. About sixteen hundred persons 

 are said to have perished. The following sketches, showing 

 roughly a section of Port Royal, before and after the earthquake, 

 will help to explain what occurred. 



Befokk. 



Abteb. 



The amount of damage done by an earthquake to buildings 

 depends very largely upon the nature of the foundations, for 

 the shock-waves of earthquakes travel at different rates of speed 

 through different substances. As a rule it may be said that the 

 more compact the substance the quicker the rate. Thus they 

 travel fastest through solid rock and slowest through loose sand. 

 The duration of the shock has everything to do with the amount of 

 damage ; consequently, in Port Royal, the sand gave way, and the 

 houses built on it collapsed, while those built on the rock, though 

 evidently shaken and thrown out of the perpendicular, remained 

 standing. 



We are able to append the following curious map, which is 

 said to be an exact plan of Port Royal before the earthquake, and 

 which shows what remained afterward. It must be observed, 

 however, that the cathedral-church, which stood near the build- 

 ing known as King's House, is unaccountably omitted. The 

 original is to be found in the library of the Institute of Jamaica, 

 at Kingston. The dotted line shows the area of rock. 



