HAYES— U. S. NAVY MV TYPE OF HYDROPHONE. 385 



£> (fathoms) ^ I -[- 22.6 tan <l> 



is plotted. The constants (C) and (L) are given in fathoms and 

 refer to the MV hydrophone installation on the U. S. S. Bernadou. 

 The curve assumes that $ is accurately determined. 



Fig. 8. 



It has been shown, however, that $^ (tt — 6) where 



d±8 



O^cos'^ 



C 



If now we take for 8 the value ±: 0.2 inches of air path (which is 

 equivalent to ± 0.87 inches of water path), this value being a con- 

 servative estimate of the precision of compensator setting, we may 



