Isaac Asimov also speculated that, in the event that he had not been killed while in the Service of the British Empire, Moseley might very well have been awarded the 1916 Nobel Prize in Physics, which, along with the prize for chemistry, was not awarded to anyone that year. Additional credence is given to this idea by noting the recipients of the Nobel Prize in Physics in the two preceding years, 1914 and 1915, and in the following year, 1917. In 1914, Max von Laue of Germany won the Nobel Prize in Physics for his discovery of the diffraction of X-rays by crystals, which was a crucial step towards the invention of X-ray spectroscopy. Then, in 1915, william Henry Bragg and william Lawrence Bragg, a British father-son pair, shared this Nobel Prize for their discoveries in the reverse Problem — determining the structure of crystals using X-rays (Robert Charles Bragg, william Henry Bragg's other son, had also been killed at Gallipoli, on 2 September 1915). Next, Moseley used the diffraction of X-rays by known crystals in measuring the X-ray spectra of metals. This was the first use of X-ray spectroscopy and also one more step towards the creation of X-ray crystallography. In addition, Moseley's methods and analyses substantially supported the concept of atomic number, placing it on a firm, physics-based foundation. Moreover, Charles Barkla of Great Britain was awarded the Nobel Prize in 1917 for his experimental work in using X-ray spectroscopy in discovering the characteristic X-ray frequencies emitted by the various elements, especially the metals. "Siegbahn, who carried on Moseley's work, received one [the 1924 Nobel Prize in Physics]." Moseley's discoveries were thus of the same scope as those of his peers, and in addition, Moseley made the larger step of demonstrating the actual foundation of atomic numbers. Ernest Rutherford commented that Moseley's work, "Allowed him to complete during two years at the outset of his career a set of researches that would surely have brought him a Nobel prize".