tact points on the gage are set 4 inches apart, 

 the apparent wave heights are only accurate to 

 4 inches and the true heights can only be 

 accurate to the same degree. 



8. Record the value for the true significant 

 height on the chart paper under the notation 

 of voltage for each run. 



9. Record the average wave period on the 

 chart paper under the value, in 8, above. 



10. Record the ma.ximum true characteristic 

 height under the value, in 9, above. 



10-28 Calibration Curve for the Electric 

 Wave Staff. — The calibration curves for the 

 motion of the staff (fig. 10-5) are not calculated 

 for use where the bottom affects the wave action 

 significantly; that is, at depths less than K the 

 wavelength. {L = 5.12T ^ unless currents are 

 present. See H. O. Pub. No. 602, Wind Waves 

 at Sea, p. 53.) 



T. PERIOD IN SECONDS 



Figure 10-5. Calibration graph of electric wave staff. 



H. O. 607 



109 



