150 ON THE nEVOLUTIONS 



portioned to the time of its previous constraint, and capable of 

 fulfilling all the conditions of Saussure's debacle, or the wave of 

 Pallas ; and the existence of these tremendous events is thus 

 indicated u priori by the Huttonian principles. 



I shall now consider, whether such traces have not been ac- 

 tually left by these Avaves, as to place the reality of their exist- 

 ence beyond all doubt. We have already alluded to some of 

 these, and shall have occasion to mention some others ; but in 

 a case of this sort, no historical, nor even traditional authority 

 need be expected ; for though no limit could well be assigned 

 to the magnitude which such a wave might actually reach, 

 there is a decided limit to the magnitude of one that could 

 be recorded ; since, by exterminating all witnesses, every 

 wave beyond a certain size would infallibly be the cause of 

 its own oblivion. Those of a moderate extent are most likely 

 to have been recorded by man, having sufficient power to pro- 

 duce the most awful impressions, and yet sparing a sufficient 

 number of witnesses to transmit the event to future genera- 

 tions. 



In our attempts to elucidate this subject, we shall refer, in 

 the first place, to specimens of this tremendous phenomenon 

 in still lower stages of its power, since they alone have been 

 recorded in an authentic and intelligible form, I mean, by re* 

 ferring to those agitations of the sea which have accompanied 

 most of the great Earthquakes in our own times, as we learn 

 from the following regular statements. 



In 



portant article to have altogether misapprehended the system proposed. In his 

 late work, {Introduction a la Geologic, Ir. Fr. p. 115.) he urges as subversive of 

 Dr HuTTOx''s views, some thermometrical observations in which the bottom of 

 the sea was found to be as cold as its surface. To urge this as an objection, 

 implies that the heat employed in this system is supposed to be for ever, and 

 everywhere, acting upon the sand of the sea ; whereas it is well known that Dr 

 HuTTON conceived that the subterranean heat, as well as that of the volcanoes, 

 was subject to short fits of activity, with ages of intermission. 



