From Webster's New Illustrated Dictionary based on the Unabridged Dictionary of Noah Webster, Revised and edited by Edward T. Roe and Charles Leonard-Stuart, Published by syndicate Publishing Company of New York in 1911.
I cut off the blurb at the bottom of this set of x-ray images. The paragraph below described The Roentgen Rays. They were called shadowgraphs. The shadowgraphs are of a hand, fish and contents of a purse. The top left picture is the Crookes tube. The image in the bottom left is a skiascope