126 SEC. 4. KINEMATICS, STATICS, AND DYNAMICS. 



VI. FALLING BODIES AND PROJECTILES. 



546. Drawing of a new Apparatus for demonstrating the 

 lateral deflection of rotating conic projectiles. 



Dr. Leopold Pfaundler, Innsbruck. 



The conic projectile A turns within the horizontal frame B on its own 

 horizontal axis, and can be put in rotation by pulling off the reel the string 

 attached to a. Fastened, on the outside of the frame, on two little hooks, 6, 1, 

 whose line of communication is perpendicular to the axis of rotation and passes 

 through the centre of gravity of the entire body, are two threads, which join 

 further up, and whose combined continuation reaches up and is tied to a 

 hook in the ceiling. 



At the back there is a steering wing C with a counter -weight D, attached 

 in such a manner that according to the position in which it is placed the effect 

 of the atmospheric resistance will be located either above or below the centre 

 of gravity of the projectile, without, however, altering the position of the 

 centre of gravity itself. The wing can be turned on its axis, or be removed 

 and replaced by a double wing C 1 with the two flat surfaces situated vertically 

 to each other. 



The following experiments can be made with this apparatus : 



]. Stability of the Axis of Rotation. 



The apparatus is put in motion to swing in a curve of five meters length by 

 taking hold of the wing and pulling it backwards, and then allowing it to drop. 

 If the projectile does not rotate, it easily turns over and will deviate from its 

 course by very slight causes ; if it rotates, it will remain parallel with its axis, 

 The wing must be given a neutral position in regard to the atmospheric 

 resistance. 



2. Lateral Motion. 



The apparatus is made to rotate to the right by the wing C being placed in 

 an upward position, when the point in flying forwards will revolve to the right. 

 If the direction of the rotation, or the position of the wing, be altered into the 

 opposite course or direction, the point will revolve towards the left. If both 

 are changed, the rotation will keep in the direction to the right. 



3. Lateral Deflection. 



The single wing C is replaced by the double wing C 1 , the flat surfaces of 

 the same being placed in a vertical and horizontal position, and the proceed- 

 ing then is the same as described before. 



Instead of the lateral motion, a parallel lateral deflection will be the result. 



The latter experiment corresponds to the actual motion of the projectiles. 

 The greater degree of velocity of the same is equalized by the larger surface of 

 the wing as regards the atmospheric resistance. 



547. Simple and Inexpensive Form of Morin's 

 Machine for demonstrating the law of falling bodies. It can be 

 made by an ordinary carpenter, at a moderate price. " 



Made and exhibited by Dr. Stone. 



548. Apparatus by General Morin for the experimental 

 demonstration of the laws of falling bodies. 



M. Digeon, Paris. 



