Photographing the Unseen 



invisible rays were flying, with an effect strange, 

 interesting and uncanny. The metal plate 

 seemed to offer no appreciable resistance to the 

 flying force, and the light was as rich and full as 

 if nothing lay between the paper and the tube. 

 "Put the book up," said the professor. 

 I felt upon the shelf, in the darkness, a heavy 

 book, two inches in thickness, and placed this 

 against the plate. It made no difference. The 

 rays flew through the metal and the book as if 

 neither had been there, and the waves of light, 

 rolling cloud-like over the paper, showed no 

 change in brightness. It was a clear, material 

 illustration of the ease with which paper and 

 wood are penetrated. And then I laid book 

 and paper down, and put my eyes against the 

 rays. All was blackness, and I neither saw nor 

 felt anything. The discharge was in full force, 

 and the rays were flying through my head, and, 

 for all I knew, through the side of the box be- 

 hind me. But they were invisible and impalpa- 

 ble. They gave no sensation whatever. What- 

 ever the mysterious rays may be, they are not 

 to be seen, and are to be judged only by their 

 works. 



I was loath to leave this historical tin box, but 

 time pressed. I thanked the professor, who was 

 happy in the reality of his discovery and the 

 music of his sparks. Then I said: "Where did 

 you first photograph living bones?" 



"Here," he said, leading the way into the 

 room where the coil stood. He pointed to a 



