304 Proceedings of the British Association for 1850. 



masses, broken into or modified by innumerable secondary 

 and smaller waves within their general body. The time in 

 which these waves passed the ship was now, on an aver- 

 age, about 15 seconds, the ship's speed being increased from 

 9 to 11 knots, and the obliquity of the ship's course to the 

 direction pursued by the waves was three points. On the 9th, 

 two days after the above condition of the waves — whilst the 

 sea yet ran high — few waves could be traced continuously 

 above 300 or 400 yards in extent along the same ridge. The 

 crests often curled over, but none so as to reach the height 

 of a 30 feet wave, and broke for a wide space, estimated at 

 50 to 100 yards in continuity. 



Miscellaneous Notes and Suggestions. — The mode adopted 

 in these researches of finding the height of waves is, said 

 Dr Scoresby, I believe, quite satisfactory, and, observed 

 with care and with relation to numbers or proportion of 

 waves, as accurate as need be. The depression of the 

 horizon, in respect to the elevation of the observer, is too 

 small to form even a correction. As the horizon from the 

 paddle-box 3^0=15 feet, had only a depression of 3' 49'', the 

 distance of the visible horizon, as seen from this elevation, 

 would be 4-45 statute miles, and the actual depression in feet 

 due to the distance of the summit of the wave when the ship 

 was in the midst of the hollow, could only be 0-18 foot, or 

 216 inches. Other modes of determining the width of a 

 wave — or the extent betwixt summit and summit — much pre- 

 ferable to that described (the only available one I could de- 

 vise) might easily be adopted, where the management of the 

 ship was in the hands of the observer. In steam- ships, the 

 simplest mode for high seas, perhaps, would be, altering the 

 speed of the ship when going in the direction of the wave or 

 against the wave ; the ratios of the times of transit of wave- 

 crests, under different rates of sailing of the ship, might yield 

 results very close to the truth. In moderate- sized waves the 

 plan adopted by Captain Stanley — whose observations I met 

 with before this meeting — seem satisfactory. But in calms, 

 or moderate weather after a storm — that is, for the determi- 

 nation of the velocities of less elevated waves — a variety of 

 processes might be available." 



