igo PLEASANT WA YS Iff SCIENCE. 



ing to about ten, Peruvian time. Since, then, the earthquake 

 was felt in Peru at half-past eight on the previous evening, 

 it follows that the wave, if it travelled directly from Peru, 

 must have taken about 13^ hours or an hour and a half 

 longer, in travelling from Peru to the Sandwich Isles, than 

 it took in August, 1868. This is unlikely, because ocean- 

 waves travel nearly at the same rate in the same parts of the 

 ocean, whatever their dimensions, so only that they are large. 

 We have, then, in the difference of time occupied by the 

 wave in May, 1876, and in August, 1868, in reaching Hawaii, 

 some confirmation of the result to which we were led by the 

 arrival of the wave simultaneously at all the islands of the 

 Sandwich group the inference, namely, that the observed 

 wave had reached these islands after reflection from the 

 Californian shore-line. As the hour when the direct wave 

 probably reached Hawaii was about a quarter past three in 

 the morning, when not only was it night-time but also a 

 time when few would be awake to notice the rise and fall of 

 the sea, it seems not at all improbable that the direct wave 

 escaped notice, and that the wave actually observed was the 

 reflected wave from California. The direction, also, in which 

 the oscillation was first observed corresponds well with this 

 explanation. 



It is clear that the wave which traversed the Pacific in 

 May, 1876, was somewhat inferior in size to that of August, 

 1868, which therefore still deserves to be called (as I then 

 called it) the greatest sea-wave ever known. The earth- 

 quake, indeed, which preceded the oceanic disturbance ol 

 1868 was far more destructive than that of May, 1876, and 

 the waves which came in upon the Peruvian and Bolivian 

 shores were larger. Nevertheless, the wave of May, 1876, 

 was not so far inferior to that of August, 1868, but that its 

 course could be traced athwart the entire extent of the 

 Pacific Ocean. 



When we consider the characteristic features of the 

 Peruvian and Chilian earthquakes, and especially when we 

 note how wide b the extent of the region over which their 



