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The Sewerage of Sea Coast Towns by Henry C. Adams
page 7 of 154 (04%)

Considered from the point of view of a person on the earth,
this primary tidal wave constantly travels round the Southern
Ocean at a speed of 13,500 miles in 24 hr. 52 min, thus having
a velocity of 543 miles per hour, and measuring a length of
13,500/2 = 6,750 miles from crest to crest. If a map of the
world be examined it will be noticed that there are three large
oceans branching off the Southern Ocean, namely, the Atlantic,
Pacific, and Indian Oceans; and although there is the same
tendency for the formation of tides in these oceans, they are
too restricted for any very material tidal action to take
place. As the crest of the primary tidal wave in its journey
round the world passes these oceans, the surface of the water
is raised in them, which results in secondary or derivative
tidal waves being sent through each ocean to the furthermost
parts of the globe; and as the trough of the primary wave
passes the same points the surface of the water is lowered, and
a reverse action takes place, so that the derivative waves
oscillate backwards and forwards in the branch oceans, the
complete cycle occupying on the average 12 hr. 26 min Every
variation of the tides in the Southern Ocean is accurately
reproduced in every sea connected with it.

Wave motion consists only in a vertical movement of the
particles of water by which a crest and trough is formed
alternately, the crest being as much above the normal
horizontal line as the trough is below it; and in the tidal
waves this motion extends through the whole depth of the water
from the surface to the bottom, but there is no horizontal
movement except of form. The late Mr. J. Scott Russell
DigitalOcean Referral Badge