NEW SPECIES OF "A^" RAYS 71 



same curve, within the limits of experimental 

 error. The study of radiations still less 

 refrangible than those I have dwelt on appeared 

 to me impracticable. To avoid confusion, I 

 was obliged to adopt a very large scale for the 

 ordinates ; this is why I could not plot on the 

 diagram the results of my former measure- 

 ments of the more refrangible " N " rays (loc. 

 cit.). These results give points situated on a 

 branch of the curve, starting from the topmost 

 point on the right, and rising almost vertically, 

 with a feeble inclination, from bottom to top, 

 and from right to left, and a slight convexity 

 turned upwards. 



Certain sources seem to emit Nj. rays ex- 

 clusively, or, at least, these rays predominate 

 in the emission. This is the case with copper 

 and silver wire, and with hard-drawn platinum 

 wire. M. Bichat has observed that ethylic 

 ether, when brought to the state of forced 

 extension, by the process discovered by M. 

 Berthelot, emits N L rays. When this state of 

 strain ceases, whether spontaneously or under 

 the action of a slight blow, the emission of N x 

 rays immediately disappears. 



