THE ROENTGENOLOGIST AND HIS SPECIALTY

It is just thirteen years since the scientific world received from Professor Roentgen his classical "First Paper," a communication which caused it to turn its interested gaze toward the little city of Würzburg, interest giving place to astonishment as the second and subsequent papers appeared. Heretofore, man could gain knowledge of invisible things only by deduction from hearing and touch, but now—to see the unseen! Small wonder that this new material for research was seized by scientific workers the world over. Roentgen's discovery was taken up with eagerness by all nations active in educational matters, and experimentation was promptly begun. Certain propositions were not accepted absolutely, argumentative attitudes were assumed, opposing theories brought forward. It must be conceded, however, that a great proportion of Roentgen's observations and assertions are to be regarded as axiomatical and remain incontrovertible after the passage of thirteen years.

By guiding the mind and hand of