The Nobel Prize in Physics 1917 was awarded to Charles Glover Barkla "for his discovery of the characteristic Röntgen radiation of the elements".
Charles Glover Barkla received his Nobel Prize one year later, in 1918. During the selection process in 1917, the Nobel Committee for Physics decided that none of the year's nominations met the criteria as outlined in the will of Alfred Nobel. According to the Nobel Foundation's statutes, the Nobel Prize can in such a case be reserved until the following year, and this statute was then applied. Charles Glover Barkla therefore received his Nobel Prize for 1917 one year later, in 1918.