31 
drawn is the type most commonly employed for purposes of illustra- 
-.tion. A dynamic section, Figure 12, formed by stations 201 to 206, 
International Ice Patrol, 1922, is shown on page 30. 
VELOCITY—HOW DETERMINED 
We may nowreturn to aconsideration of equation (f), page 24, in order 
to find the velocity of the current between stations 206 and 205, by 
substituting at the same time for d, and d; the values as found at the 
six levels of observation of the two foregoing stations. Since the 
velocity is the term desired, equation (f), page 24, may be written 
in the following form: 
(da — dy) 10° 
(open ian’ <qe- 7 ~~ 8 
where ¢m=41°—10’, the mean latitude of stations 206 and 205. The 
value of 10°. 2w sin ¢, by Table VI, page 32, is found to be equal to 9.60. 
The multiple 10° is introduced simply to bring the velocity values into 
centimeter-gram-second terms. L, which is the distance between 
stations, is equal to 32 miles, or 59 kilometers. (See Table VII, p. 33.) 
Depth in dynamic meters 
Stations i 
50 125 250 450 750 
FG = oe Sete Ee BES EE a aaa 48. 71750 |121.75713 |243. 40776 |437. 84276 | 729. 08476 
PAB case ofa re Sega 48. 68875 |121. 69188 |243. 27250 |437. 59850 | 728. 72150 
pS se be ee ee 0.02875 | 0.06525 | 0.13526 | 0, 24426 0. 36326 
If we treat the values of d,—d, as whole numbers and divide them 
by the value of 2 sin ¢nL 10°, the latter of which is found equal to 
569.28, we obtain the following: 
50 225 250 450 | 750 
If it is assumed that ¢; is equal to zero at a depth of 750 decibars 
(meters), then the following velocities are furnished at the various 
levels of observation, from the surface downwards. (Ifitis desired to 
express velocities in terms of knots per hour, 10 cm./sec. is equal 
approximately to 0.2 knots per hour.) 
Meters or decibars 0 50 125 | 250 450 750 
(Wo —jintom!/Secke sua le oases aoe yoo nee eee 64 59 52 
Cr TRG EDT So ARES EE Ee eae 1.3 152 1.0 
