168 



Scientific Proceedings^ Royal Dublin Society. 



Table I. 



Some further experiments were carried out with a view to reducing the 

 time interval to a still smaller value. It is not possible to do this simply by- 

 mounting the wires closer together in the arrangement just described. It 

 would seem that a great part of the percentage error of the above results is 

 due to unequal stretching of the wires before breaking, and, of course, this 

 effect becomes more and more important as the separation of the wires is 

 diminished. To avoid this, several modifications were considered, and one was 

 tried which appeared promising. Unfortunately, the work had to be abandoned 

 before many observations with it had been carried out. 



In this arrangement, instead of breaking the wires, the bullet was caused 

 to strike them in such a manner as to lift them from two metallic supports, 

 thereby breaking the circuits. The wires were sxibseqicently broken by the 

 bullet, but the breaking bore no part in the actual operation of the apparatus. 



