The Fundamental Level of the Iron Atom

IN a paper on the under-water spark spectrum of iron in Phil. Mag. (February 1926) and in a letter to NATURE (March 13, 1926, p. 380), Mr. N. K. Sur raises objections against the main result of the writer's classification of the iron spectrum (Zeit. f. Phys., 23, 135, 1924; 26, 1, 1924), namely, the fact that a ⁵D term is the lowest term in the energy diagram and that consequently ⁵D corresponds to the normal state of the iron atom.