MAN FROM THE FARTHEST PAST 
the meeting of the British Association for the Advance- 
ment of Science in the year 1914. A volunteer officer in 
the ‘““Territorials,’’ Moseley hurried from the British As- 
sociation scientific assembly on the outbreak of the Great 
War, to be instantly killed by a Turkish bullet at Gallipoli, 
August 10, 1915. He lived only twenty-eight ae but 
his name will be remembered forever. 
Moseley’s law finds its interpretation in the structure of 
the atoms of the chemical elements. Hydrogen has one 
orbital electron, helium two, lithium three, beryllium four, 
and so on, advancing by unit steps, to uranium, the last of 
the known chemical elements, with ninety-two electrons 
arranged in a multitude of orbits all focusing about the 
central nucleus. | 
Not only in the infinitesimal domain of the atoms, but in 
the vast spaces of the starry systems, an orderly gradation 
of qualities prevails. In size, in brightness, in spectrum, 
in density, in temperature, the nebulae and the stars pre- 
sent an orderly series of great impressiveness. Invisible to 
the eye, because of tremendous distance, but readily photo- 
graphed by great telescopes, the heavens contain hun- 
dreds of thousands of such objects as are shown in Plate 2. 
We see there a series of forms ranging from irregular 
through spherical hazy masses, thence, through gradual 
elongation, to pronounced spindle shape, and finally to the 
branched spirals. It is believed that here we see the evolu- 
tion of a starry galaxy such as our own. At first unformed, 
gravitation settles the gaseous mass into a sphere; rota- 
tion elongates it; still greater motion tends to produce the 
spindle shapes; which, with increased velocities and tidal 
forces, produce the two-branched spirals; from which, at 
length, separate the stars. All of this observedly probable 
train of events conforms to known laws of fluids. 
But the stars also show progression after their birth, of 
which a striking evidence is given by the group of stellar 
spectra shown in Plate 78 in Volume 2 of this SrriEs. By 
many years of observation along many lines of attack, 
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