of researches into both the character of the new force and its physiological possibilities. In the next few weeks these strange announcements will be trebled or quadrupled, giving the best evidence from all quarters of the great future that awaits the Röntgen rays, and the startling impetus to the universal search for knowledge that has come at the close of the nineteenth century from the modest little laboratory in the Pleicher Ring at Würzburg. [Illustration: A HUMAN FOOT PHOTOGRAPHED THROUGH THE SOLE OF A SHOE. THE SHADING SHOWS THE PEGS OF THE SHOE, AS WELL AS TRACES OF THE FOOT. From a photograph by Dr. W.L. Robb of Trinity College.] [Illustration: PHOTOGRAPHING A FOOT IN ITS SHOE BY THE RÖNTGEN PROCESS.--A PICTURE OF THE ACTUAL OPERATION WHICH PRODUCED THE PHOTOGRAPH SHOWN ON PAGE 408. From a photograph by Dr. W.L. Robb of Trinity College. The subject's foot rests on the photographic plate.] On instruction by cable from the editor of this magazine, on the first announcement of the discovery, I set out for Würzburg to see the discoverer and his laboratory. I found a neat and thriving Bavarian city of forty-five thousand inhabitants, which, for some ten centuries, has made no salient claim upon the admiration of the world, except for the elaborateness of its mediæval castle and the excellence of its local beer. Its streets were adorned with large numbers of students, all wearing either scarlet, green, or blue caps, and an extremely serious expression, suggesting much intensity either in the contemplation of Röntgen rays or of the beer aforesaid. All knew the residence of Professor Röntgen (pronunciation: "Renken"), and directed me to the "Pleicher Ring." The various buildings of the university are scattered in different parts of Würzburg, the majority being in the Pleicher Ring, which is a fine avenue, with a park along one side of it, in the centre of the town. The Physical Institute, Professor Röntgen's particular domain, is a modest building of two stories and basement, the upper story constituting his private residence, and the remainder of the building being given over to lecture rooms, laboratories, and their attendant offices. At the door I was met by an old serving-man of the idolatrous order, whose pain was apparent when I asked for "Professor" Röntgen, and he gently corrected me with "Herr Doctor Röntgen." As it was evident, however, that we referred to the same person, he conducted me along a wide, bare hall, running the length of the building, with blackboards and charts on the walls. At the end he showed me into a small room on the right. This contained a large table desk, and a small table by the window, covered with photographs, while the walls held rows of shelves laden with laboratory and other records. An open door led into a somewhat larger room, perhaps twenty feet by fifteen, and I found myself gazing into a laboratory which was the scene of the discovery--a laboratory which,