10 Proceedings of the Royal Irish Academy. 



In the fifth century, it seems that a remarkable earthquake took 

 place which affected Tara. It occnrred. (it is said) when Odran, St. 

 Patrick's charioteer, was assassinated. ''And the cleric was angered," 

 says the author of the Senchus Mor, " and raised up his hands towards 

 his Lord, and remained in the attitude of prayer with his hands crossed, 

 and there came a great shaking and earthquake at the place, and dark- 

 ness came upon the sun, and there was an eclipse ; and they say that 

 the gate of hell was then opened, and that Teamair was in danger of 

 being overturned, and then it was that Teamair became inclined." 



It thus appears, not only that we have had earthquakes in this 

 country, but that the farther we go back in authentic history, the 

 more striking seem to have been their' effects. This constant increase 

 in seismical energy appears to point to the occurrence of still more 

 vehement action in preceding periods — in those periods, for instance, 

 to which so many eruptions of lakes and rivers are attributed. 



Secondly : Are the phenomena recorded in our annals such as would 

 have been produced by seismical action, and by that alone ? We have 

 seen that no other imaginable cause was competent to produce such 

 results ; it now remains to prove that seismical energy can produce 

 them, and to give cases showing it to have wrought out analogous 

 effects. 



At the outset, it is noticeable that almost all the lakes and rivers 



river Teviot dried up suddenly, andremaiued dry fur two hours, within a short time of 

 the occurrence of an earthquake at Messina. Again, however, the same river suddenly 

 dried up for four hours, nineteen daj's after a shock had been felt in 1786, at Campsic 

 and Strathblaine, north of Glasgow. In other cases, however, the connection is un- 

 mistakeable. Thus, in 1802, whilst the ground moved " like waves of the sea," and 

 partial subsidences and upheavals were noted, it is related that "the waters of the 

 Orinoco rose so high [apjjarently] as to leave a large part of the river dry," correctly 

 speaking, the river bed was upheaved. In 1820 a small river in east Gothland, Sweden, 

 stopped at a certain spot, so that its bed Avas crossed dry-shod. In 1830, the Douro, in 

 Portugal, suddenly dried, between Roa and Aranda, at 2 o'clock in the morning, and 

 resumed its course at 10 A. m.. The river Alba de Tormes was interrupted in like 

 manner. Garnier, in his Meteorologie relates, that, in 1833, after an earthquake had 

 been felt at Linkbping in Sweden, on the following niglit the river near the bridge of 

 Montala stopped, and was raised np like a kind of sea. The bed could be passed dry- 

 shod, although in general 60,000 tons of water pass under the bridge per minute. 



If it be also remembered that, owing to earthquake action, the sea has, at times, 

 retired from bays and the coast, rushing up again to a great height, it seems possible that 

 the passage of the Israelities on dry ground through the Red Sea was assisted (physically) 

 by seismical action. A strong east wind is mentioned as having caused the sea to go 

 back, and pillars of cloud and fire were seen. It is to be remarked that clouds, flashing 

 of fire, fire-balls, fiery red vapours, as well as thunder and lightning, frequently accom- 

 pany earthquakes. In 1802, at Cahors (in France), and for forty leagues around it, a 

 loud explosive noise was heard, preceded by a flame, directed fi'om west to east, and 

 accompanied bv a southerly wind. At Eeauvais, simultaneously with a sbock, a globe of 

 fire was observed moving from east to west, which disappeared with a loud explosion. 

 At Albugnol, in 1804, the heavens were obscured by a dark mist, whicli resolved itself 

 into a cloud, when in ten minutes five terrible flashes of fire issued, and after each flash 

 a shock took place. 



