If we take Vt =1, t = 50 meters, then we shall have 
a QbK/d A 3.0K/0 a7 
This is a slope about 3 em per 100 km, or about 2 inches per 100 nautical 
miles. The stress Tie = 1 corresponds to a wind of speed about 6 or 7 m/sec. 
’ When h = 100 m the slopes is half as large. 
The fact that the slope is very smal] when b/Dy is small, means that 
the influence of the sarth’s rotation is lergely pressed down by the bottom 
friction. As the depth of the water approaches Dy gradually, the earth's 
rotation becomes a more and more important factor. 
Although these results are all purely theoretical ones, there ia no 
réason a they are of no practical application. Comparison with great 
mmbers of observations will give som idea about the magnitudes of both 
horizontal and vertical mixing eefficients. 
VII. Changs of Sea Level in an Offshore Direction. 
Determination of the slope of the sea surface enables us to know how 
the surface of the sea rises or falls as we are removed from the coast. 
Because the water surfaces is assumed to neither rise nor fall in e direction 
parallel to the coast, we have only to check the chatige of sea level in an 
offshore direction. 
An approximate formula to compute a curve y = F{x) from the values of 
uy pesos at two points separated by AX is 
qa +2 f(A) 1B), a2 
4i-] 
where (24) ws (Ft £) are the values of y at 7 and X) 
Kae -/ Sh 
=lB= 
