ANNUAL ADDRESS OF THE PRESIDENT. LXV 
progress, while, on the other hand, the chemists have eagerly 
adopted it. As the English yard and pound are the direct descend- 
ants of the Chaldean-Babylonian natural cubit and mina, it is not 
surprising that the yard should be only 0°48 of an inch shorter 
than the double cubit, and the avoirdupois pound only 665 grains 
lighter than the Babylonian commercial mina; but, considering the 
origin of the metric system, it is rather curious that the meter is 
only 1:97 inches shorter than the Chaldean double royal cubit, and 
the kilogram only 102 grains heavier than the Babylonian royal 
mina. Thus, without much exaggeration, we may regard the pres- 
ent English and French fundamental units of length and mass as 
representing respectively the commercial and royal units of length 
and mass of the Chaldeans of four thousands years ago. 
Science tells us that the energy of the solar system is being slowly 
dissipated in the form of radiant heat; that ultimately the sun will 
grow dim; life will die out on the planets; one by one they will 
tumble into the expiring sun; and at last darkness and the bitter 
cold of the absolute zero will reign over all. In that far-distant 
future imagine some wandering human spirit to have penetrated to 
a part of space immeasurably beyond the range of our most pow- 
erful telescopes, and there, upon an orb where the mechanical arts 
flourish as they do here, let him be asked to reproduce the standards 
of length, mass, and time with which we are now familiar. In the 
presence of such a demand the science of the seventeenth and eight- 
eenth centuries would be powerless. The spin of the earth which 
measures our days and nights would be irretrievably gone; our yards, 
our meters, our pounds, our kilograms would have tumbled with the 
earth into the ruins of the sun, and become part of the debris of the 
solar system. Could they be recovered from the dead past and live 
again? The science of all previous ages mournfully answers, No; 
but with the science of the nineteenth century it is otherwise. The 
spectroscope has taught us that throughout the visible universe the 
constitution of matter is the same. Everywhere the rythmic motions 
of the atoms are absolutely identical, and to them, and the light 
which they emit, our wandering spirit would turn for the recovery 
of the long-lost standards. By means of a diffraction grating and 
an accurate goniometer he could recover the yard from the wave 
length of sodium light with an error not exceeding one or two thou- 
sandths of an inch. Water is everywhere, and with his newly re- 
