Transactions Society Naval Architects and Marine Engineers, Vol. 24, 1916. Plate 125. 
To illustrate paper on “The Commercial Gyroscopic Compass,” 
by Elmer A. Sperry, Esq., Member. 
Fig. 5.—TRANSMITTER. 
Fic. 6.—PorTABLE REPEATER FOR 
SUBMERGED TORPEDO FIRE. 
Fic. 7—Smatt Type Repeatinc Compass MountTeD 
on GrmMBAL RING. 
