Transactions Society Naz'al Architects and Marine Engineers, Vol. 32, 11)14. Plate 4^. 



To illustrate paper on "Submarine Signaling and a Proposed Method of Safe Navigation 

 in Fog," by Commander F. L. Sazvyer, U. S. N., Member. 



Jl£CEIVING TANK FiG.I. 



Air Bell. 

 Weight 85 lb. 

 Vibrations per sec. 350. 



Submarine Bell. 

 Weight 210 lb. 



Vibrations per sec ■\ 



J in air 1280 

 in v^ter 1215. 



Fig. 2- — Sketch Showing Difference between Air Bell and Sub- 

 marine Bell. 



Fig. -4. — Sketch Illustrating Relative Distances the Submarine 

 Bell can be Heard at Different Angles. 



