Di Bella 



Fig. 3 - Expansion of Fig. 2 to 

 two rotating masses with two 

 propulsive effects in a single 

 shaft revolution 



same instant, mass m' is at Pj and after a successive rotation of 180° it passes 

 to Pq and generates its propulsive effect there. 



The arrangement of the device with three toothed wheels (one fixed and 

 two mobile) and two rotating masses, indicated in Fig. 4, allows two propulsive 

 effects to be executed for each turn of the motor shaft: one is generated by m 

 when it is at Pi and the other is generated by m' when, after a 180° rotation 

 of the motor shaft, it is at point P^ . 



11, instead, the two rotating masses are arranged as indicated in Fig. 5, 

 then the device, for each turn of the motor shaft, generates at the same instant 

 two propulsive effects, symmetrical in respect to the y axis: one is generated 

 by m at the moment in which it is at P^ and the other is generated by m' which 

 at the same moment is at P/. This description shows how effectively the motion 

 of the devices has been observed, and can be verified by arranging the same de- 

 vices on a horizontal plane and setting them in motion. 



EQUATIONS OF THE MOTION OF THE MASS WITH 

 DEVICES FIXED TO THE SUPPORTING PLANE 



It seems rather difficult to be able to write the general equations for the 

 motion of the tested devices; first, because the cause of the forward motion in 

 a desired direction, instead of a back- and -forth motion, is not very clear; 

 second, because the motion of the devices is accompanied by strong vibrations, 

 depending on the number and weight of the rotating masses, the rotatory speed 

 of the motor shaft, the reactions of the support, etc. 



Consequently, we can do nothing but limit ourselves to the case in which 

 the bases of the devices are not free to move on the supporting plane, but are 

 fixed rigidly to this plane. Likewise, for simplicity, we have to suppose that 

 the mass is concentrated in one point, that the arms of length R and r and the 



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