1847.] including Notices of Sumatra, the Malay Peninsula, §c. 555 



owing to its progressive lateral contraction, as is seen more markedly in 

 bores. 



2. The opening of fissures and evacuation through them of black 

 fluid matter. The spasmodic expansion and contraction of fissures con- 

 tinued after the shock. 



3. The disruption of portions of mountains or landslips. 



4. The elevation of tracts of land. 



5. The greater violence of earthquakes on hills. This was observed 

 at Pinang in 1843. Marsden remarks that houses situated on a low 

 sandy soil are least affected, and those which stand on distinct hills 

 suffer most from the shocks. 



6. The connection between earthquakes and the condition of the 

 atmosphere. To what is stated by Lieut. Crooke respecting the great 



* drought which preceded the earthquake at Jambi, the following extract 

 from Marsden relative to Sumatran earthquakes in general may be 

 added : — " Earthquakes have been remarked by some to happen usually 

 on sudden changes of weather, and particularly after violent heats ; but 

 I do not vouch this upon my own experience, which has been pretty 

 ample." The earthquake of 1843 occurred during one of the longest 

 and severest droughts that had ever happened in Pinang. This 

 drought, which was attended with oppressive heat and occasional hot 

 winds, never before experienced within the memory of the residents, 

 appears to have extended over the northern part of Sumatra. 



Note. 

 When the foregoing paper was written I had not seen the talent- 

 ed and eleborate memoir on Indian Earthquakes by Lieutenant R. B . 

 Smith, which I received by the Iiooghly. The portions at which I 

 have had time to glance suffice to show that it contains a mine of 

 wealth. The above notices of Malayan earthquakes, however meagre, 

 may serve to connect his researches with the Indian Archipelago, re- 

 specting the general geology and recent volcanic disturbances of which 

 I am collecting information. Meantime the subjoined account which 

 has been furnished me by my brother, abridged from the official report 

 of the Alcalde Mayor of the province of Cagayan in the Island of Luzon, 

 of an earthquake attended by the subsidence of two hills and by a 

 violent hurricane which occurred there on the night between the /th 

 and 8th October last, may prove interesting. It will appear in the 



