Di Bella 



Fig. 17 - Float with flat 

 bottom and ve rtical 

 sides , 4 meters long, 0.74 

 meters wide, 77 kg dis- 

 placement, having a 2- 

 mass device and moving 

 at 0. 36 m/sec 



Fig. 18 - Hull of float in Fig. 

 17, showing the wave produced 

 by its lateral displacements 



Fig. 19 - Very light hull, 

 1.40 meters long, flat 

 bottom, driven by a device 

 with two masses 



Tests in Immersion 



These tests were carried out by placing a two- mass device on a com- 

 pletely immersed hull, 3.10 meters long and 0.48 meters wide, with 2pi/d = 

 2 X 4.90/470 = 0.208 and 2r/L = 0.18/3.10 = 0.116. The resulting speed was 

 very low, but it was sufficient to demonstrate that the device functions even 

 when placed on a hull that is completely immersed. However, because of the 

 excessive dimensions of the device, its weight, and its very low speed, it can- 

 not at presence have practical applications for navigation in immersion. 



1386 



