Mathematical and Physical Science. 297 



from them, were entirely uninfluenced by. and separate from 

 theory. They form but a contribution to this interesting 

 branch of natural phenomena; but I offer them the more 

 readily from the circumstance of their entire independency 

 and speciality. It was in our return voyage from Ame- 

 rica that the highest seas occurred, when the circumstances 

 adapted for interesting observations were singularly favour^ 

 able ; for, whilst the magnitude and the peculiar construc- 

 tion of the upper works of the ship — the Hibernia — afforded 

 various platforms of determinate elevation above the line 

 of flotation for observations on the height of the waves, 

 the direction of the ship's course, with respect to that of 

 waves, was generally so nearly similar as to yield the most 

 advantageous agreement or accordance for observations on 

 their width and velocity. These observations I shall extract, 

 in their order, from my Journal kept during the homeward 

 passage. My first observation worth recording is under the 

 date of March 5, 1848, when the ship was in latitude about 51°, 

 and longitude (at noon) 38° 50' W.^ — the wind then being about 

 WSW., and the ship's course, true, N. 52° E. At sunset of 

 the 4th the wind blew a hard gale, which, with heavy squalls, 

 had continued during the night ; so that all sail was taken 

 in but storm- stay sail forward. The barometer stood at 29*50 

 at 3 P.M., but fell so rapidly as to be at 28*30 by 10 the next 

 morning. In the afternoon of this day I stood some time on 

 the saloon deck or cuddy roof, — a height, with the addition 

 of that of the eye, of 23 feet 3 inches above the line of flota- 

 tion of the ship, — watching the sublime spectacle presented 

 by the turbulent waters. I am not aware that I ever saw 

 the sea more terribly magnificent. I was anxious to ascertain 

 the height of these mighty waves ; but found almost every 

 wave rising so much above the level of the eye, as indicated 

 by the intercepting of the horizon of the sea in the direction 

 in which they approached us, as to yield only the minimum 

 elevation, and to shew that the great majority of these roll- 

 ing masses of water possessed a height of considerably more 

 than 24 feet (including depression as well as altitude), or 

 reckoning from the mean level of the sea, of more than 12 

 feet. Exposed as the situation was, I then adventured to 



