Di Bella 



the theoretical and experimental point of view. As to the theoretical viewpoint, 

 it will be necessary to be able to form the general equations for the motion of 

 the device, to find again the trajectory indicated in Fig. 27, and to demonstrate 

 that the displacement +Sj ceases to exist if there is effected a lack of friction 

 resistance because of the contact of the device with the surface of the support. 

 As to the experimental viewpoint, it is a question of finding a laboratory test in 

 which the friction resistance is small enough to remove the possibility that the 

 device might move. 



For now, we have established the fact that a vehicle, by means of an "in- 

 ternal" mechanism, can move in the presence of very little friction. 



CONCLUSIONS " -•' 



During the tests that were made, the best results were obtained with the 

 device indicated in Fig. 3; thus, we intend to refer to this device in our final 

 summary considerations. 



1. The device, as has been mentioned, does not generate a continuous 

 thrust, as happens for example in the case of the propeller, but produces two 

 propulsive effects for each turn of the motor shaft. Meanwhile, in the interval 

 between one propulsive effect and the other, the device vindergoes the reaction 

 of the vehicle that it must thrust. It follows from this that the functioning of 

 the device depends upon the type of vehicle, and on the point and way in which 

 it is placed on the vehicle. 



2. The number of turns of the motor cannot be notably increased, because 

 beyond a certain value the device begins to jump aroimd on the supporting plane, 

 and the absorbed power is thus dispersed in vibrations. 



3. Up to the present time, it has not been possible to combine more than 

 two rotating masses in such a way as to be able to have more than two propul- 

 sive effects for each turn of the motor shaft. Even after having recognized 

 the great importance that the resolution of this problem would have, we have 

 only been able to devote rather limited time to it. 



4. The device generates vibrations that may be tolerable on ships and 

 floats in general, but rather unpleasant in land vehicles. It is necessary to 

 foresee an arrangement of mechanisms that can absorb the vibrations. In the 

 case of automobiles, if the device is attached to the axis of the rear wheels, 



it is necessary to anticipate an arrangement of shock-absorbers that will pre- 

 vent the vibrations from passing from the axis of the wheels to the chassis. 



5. The weight and dimensions of the device may constitute a serious ob- 

 stacle for its use on ships. It depends on the speed it has to reach. If it is 

 limited to the minimum speed needed to move a ship in port, with a calm sea 

 and without wind, then the weight and the dimensions of the device may be 

 tolerable. Numerical indications concerning this problem will be obtained 

 only after having made tests on some ships. 



1394 



