30 REPORT—1850. 
It should be observed, too, that the headway of the ship, in the direction of the 
course of the wave, being a known quantity, was favourable to the accuracy of the 
estimate. For, assuming an error in the width of the waves to have occurred, say to the 
amount of one-twelfth of the whole, or 49 feet, the effect upon the calculated velocity 
of the wave would have been only about a sixteenth, or 2°16 miles per hour*. 
The form and character of these deep-sea waves became, at the same time, inter- 
esting subjects of observation and consideration. In respect to form, we have per- 
petual modifications and varieties from the circumstance of the inequality of opera- 
tion of the power by which the waves are formed. Were the wind perfectly uniform 
in direction and force, and of sufficient continuance, we might have, in wide and 
deep seas, waves of perfectly regular formation. But no such equality in the wind 
ever exists. It is perpetually changing its direction, within certain limits, and its 
force, too, both in the same place and in proximate quarters. » Innumerable dis- 
turbing influences are therefore in operation, generating the varieties more or less 
observable in natural sea-waves. 
In regard to my own observations of the actual forms of waves, nothing particularly 
new, indeed, could be expected from an inguiry of this kind, in regard to phenomena 
falling within the perpetual observation of sea-going persons ; yet, at the risk of 
stating what might be deemed common, I will venture to transcribe from my notes 
made with the phenomena before me, the leading characteristics which engaged my 
attention. 
During the height of the gale (March 6th) the form of the waves was less regular 
than after the wind had for some time begun to subside, Though in many cases, 
when the sea was highest, the succession of the primary waves was perfectly distinct, 
it was rather difficult to trace an identical ridge for more than a quarter to the third 
of a mile. The grand elevation, in such cases, sometimes extended by a straight 
ridge, or was sometimes bent as of a crescent form, with the central mass of water 
higher than the rest, and not unfrequently with two or three semi-elliptical mounds 
in diminishing series, on either side of the highest peak. 
These principal wayes, too, it should be noted, were not continuously regular, but 
had embodied in their general mass many minor, secondary and inferior waves. 
Neither did the great waves go very prevalently in long parallel series like those re- 
tarded by shallow water on approaching the shore, but Sey now and then changed 
into a bent cuneiform crest with breaking accumulating peaks. 
On the following morning, March 7, after a second stormy night, wind S.S.W. 
(true), we had a heavy and somewhat cross sea (from the change of wind from 
W.S.W. to 8.S.W.). But almost unabated magnitude of the more westerly waves 
indicated a continuance of the original wind at some distance astern of us. The 
gale had moderated at daylight, and the weather became fine; but as the sea still 
kept high, its undulation became more obvious and easily analysed. At three in 
the afternoon, when about a third part of the greater undulations averaged about 
24 feet from crest to hollow in height, these higher waves could be traced, right 
and left, as they approached the ship to the extent of a quarter of a mile on an 
average, more or less. Traced through their extent the ridge was an irregular round- 
backed hill, precipitous often on the leeward side, of waters. The undulations, in- 
deed, as to primary waves, consisted mainly of these round-backed 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 average, about 
fifteen seconds, the ship’s speed being increased from nine to eleven 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 to 400 yards in ex- 
tent 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. 
* To show the effect of an extreme case, we shall assume an error in the estimated width of 
the wave of one-half, calling it 279’ instead of 559 feet. The resulting velocity of the wave 
would still be 2114 miles ; the error of one-half the width producing an error only of one- 
third in the velocity. 
