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MISCELLANEOUS 



9611 



In table 32 are given the velocities (in meters per second) for various temperatures 

 at surface atmospheric pressure and at an assumed salmity of 35.0 7oo- The correction 

 to be applied for any other salinity is given in table 33 ; it is subtractive for salinities 

 less than 35.0 °/oo and additive for salinities above 35.0 7oo- The correction for 

 pressure at latitude 45° is given in table 34; it is always additive. The pressure cor- 

 rection varies not only with hydrostatic pressure, but also with gravity and therefore, 

 slightly with latitude; but the mean values in table 34 are sufficiently accurate for 

 all surveying purposes. The pressure correction is nearly proportional to depth, 

 and for depths less than 1,000 fathoms, it may be found with sufficient accuracy by 

 dividing the depth (in fathoms) by 30 — the result being the correction in meters 

 per second. 



Table 32. — Velocity of sound in sea water — in meters per second, at surface atmospheric pressure 



and salinity 35 °Uo- 



