An Experiment relating to Atomic Orientation. 463 



The curves in fig. 1 have all been copied from the results 

 of Table I. In each case they are for an aerial wire 200 ft. 

 long, and they have all been collected to a common point at 

 the top in order to show most clearly their relative shapes. 



To check these results a few photographs of an actual 

 trailing aerial complying as far as possible with case I. were 

 taken. It was found impossible to get the whole aerial 

 (200 ft.) into one photograph, and as it has been shown that 

 the shape of the lower portion is independent of the length, 

 two photographs were taken — one of the upper end only with 

 the full length out to obtain the angle of emission, and one 

 of a length of 50 ft. of wire only which could be obtained 

 on one plate to show the general shape of the lower portion. 

 From the first the angle of emission was found to be about 

 62°, the theoretical angle being about 61°. 



Fig. 2 shows the second curve, the full line being the shape 

 of the 50 ft. aerial actually traced from the photograph and 

 the broken line the theoretical shape. 



Considering the difficulty in obtaining an accurate repre- 

 sentation of the theoretical conditions when actually flying, 

 these two show very good agreement. 



It was therefore taken that the assumptions made in the 

 course of the calculations were justified and that the curves 

 give the actual aerial shapes with a fair degree of accuracy. 



XLIII. An Experiment relating to Atomic Orientation. 

 By T. R. Merton, J).Sc* 



IN modern theories of the structure of the atom the 

 supposed arrangement is of such a kind that the atom 

 may be described as having an axis perpendicular to the 

 plane in which an electron, or a ring or rings of electrons 

 are in rotation. Since it is well established that the atoms 

 in a crystal are arranged in a perfectly regular manner, it is 

 of interest to inquire whether the axes of these atoms are 

 also oriented in a regular manner, or whether their directions 

 are distributed at random. Of these two possibilities the 

 former seems a priori to be the more probable. Calling this 

 the first assumption, an experiment arising from the appli- 

 cation of a second assumption seemed worthy of trial. The 

 second assumption is that the direction in which the a and 

 /3 particles are ejected from a radioactive atom is related to 

 the orientation of the atomic axis. If both assumptions are 

 correct there should be a difference in the a and /3 ray 

 activities from the different faces of certain crystals of radio- 

 active substances. It may at once be stated that no such 

 * Communicated by Prof. Sir E. Rutherford, F.RS. 



